Zeb2 regulates the balance between retinal interneurons and muller glia by inhibition of BMP-Smad signaling.
Abstract The interplay between signaling molecules and transcription factors during retinal development is key to controlling the correct number of retinal cell types. Zeb2 (Sip1) is a zinc-finger multidomain transcription factor that plays multiple roles in central and peripheral nervous system development. Haploinsufficiency of ZEB2 causes Mowat-Wilson syndrome, a congenital disease characterized by intellectual disability, epilepsy and Hirschsprung disease. In the developing retina, Zeb2 is required for generation of horizontal cells and the correct number of interneurons; however, its potential function in con...
Source: Developmental Biology - September 17, 2020 Category: Biology Authors: Menuchin-Lasowski Y, Dagan B, Conidi A, Cohen-Gulkar M, David A, Ehrlich M, Giladi PO, Clark BS, Blackshaw S, Shapira K, Huylebroeck D, Henis Y, Ashery-Padan R Tags: Dev Biol Source Type: research

Akirin is critical for early tinman induction and subsequent formation of the heart in Drosophila melanogaster.
In this study, we identify the highly conserved transcription cofactor Akirin as a key factor in the earliest induction of tinman by the Twist transcription cofactor. akirin mutant embryos display a variety of morphological defects in the heart, including abnormal spacing between rows of aortic cells and abnormal patterning of the aortic outflow tract. akirin mutant embryos have a greatly reduced level of tinman transcripts, together with a reduction of Tinman protein in the earliest stages of cardiac patterning. Further, akirin mutants have reduced numbers of Tinman-positive cardiomyoblasts, concomitant with disrupted pat...
Source: Developmental Biology - September 17, 2020 Category: Biology Authors: Howard AM, Milner H, Hupp M, Willett C, Palermino-Rowland K, Nowak SJ Tags: Dev Biol Source Type: research

The Drosophila MLR COMPASS-like complex regulates bantam miRNA expression differentially in the context of cell fate.
Abstract The conserved MLR COMPASS-like complexes are histone modifiers that are recruited by a variety of transcription factors to enhancer regions where they act as necessary epigenetic tools for enhancer establishment and function. A critical in vivo target of the Drosophila MLR complex is the bantam miRNA that regulates cell survival and functions in feedback regulation of cellular signaling pathways during development. We determine that loss of Drosophila MLR complex function in developing wing and eye imaginal discs results in growth and patterning defects that are sensitive to bantam levels. Consistent with...
Source: Developmental Biology - September 15, 2020 Category: Biology Authors: Ford DJ, Zraly CB, Perez JH, Dingwall AK Tags: Dev Biol Source Type: research

Yes-associated protein 1 translocation through actin cytoskeleton organization in trophectoderm cells.
This study focused on the mechanisms involved in YAP1 release from TE nuclei after blastocoel contraction in bovine blastocysts. The blastocysts contracted by blastocoel fluid aspiration showed that the YAP1 translocation from nucleus to cytoplasm in the TE cells was concomitant with the protruded actin cytoskeleton. This YAP1 release from TE nuclei in the contracted blastocysts was prevented by actin disruption and stabilization. In contrast, Y27632, which is a potent inhibitor of Rho-associated coiled-coil containing protein kinase 1/2 (ROCK) activity, was found to promote YAP1 nuclear localization in the TE cells of con...
Source: Developmental Biology - September 15, 2020 Category: Biology Authors: Yamamura S, Goda N, Akizawa H, Kohri N, Balboula AZ, Kobayashi K, HanakoBai, Takahashi M, Kawahara M Tags: Dev Biol Source Type: research

Mouse models to study the pathophysiology of combined methylmalonic acidemia and homocystinuria, cblC type.
e; RA Abstract Combined methylmalonic acidemia and homocystinuria, cblC type, is the most common inherited disorder of cobalamin metabolism and is characterized by severe fetal developmental defects primarily impacting the central nervous system, hematopoietic system, and heart. CblC was previously shown to be due to mutations in the MMACHC gene, which encodes a protein thought to function in intracellular cobalamin trafficking and biosynthesis of adenosylcobalamin (AdoCbl) and methylcobalamin (MeCbl). These coenzymes are required for the production of succinyl-CoA and methionine, respectively. However, it is curr...
Source: Developmental Biology - September 14, 2020 Category: Biology Authors: Chern T, Achilleos A, Tong X, Hsu CW, Wong L, Poché RA Tags: Dev Biol Source Type: research

Dynamic optima in cell sizes during early development enable normal gastrulation in zebrafish embryos.
Abstract Cell migration is the main driver of the evolutionarily conserved process of gastrulation, which shapes metazoan embryo morphology. The molecular and cellular mechanisms of cell migration during gastrulation though well researched lacks an understanding of the contribution of cell sizes to collective cell migration. This is especially important during the early phase of metazoan development, which is dominated by constantly changing cell sizes in the background of which cells migrate en mass to shape the embryo. Here we investigate this phenomenon in zebrafish embryos, a model system in which early cell d...
Source: Developmental Biology - September 13, 2020 Category: Biology Authors: Menon T, Borbora AS, Kumar R, Nair S Tags: Dev Biol Source Type: research

Retinoic acid signaling regulates proliferation and lamina formation in the developing chick optic tectum.
In this study, we have identified the presence of differential retinoic acid (RA) signaling along the rostro-caudal and dorsoventral axis of the tectum. We show for the first time that loss of RA signaling in the anterior optic tectum, leads to an increase in cell proliferation and gross changes in the morphology manifested as defects in lamination. Detailed analysis points to delayed migration of cells as the plausible cause for the defects in lamina formation. Thus, we conclude that in the optic tectum, RA signaling is involved in maintaining cell proliferation and in regulating the formation of the tectal laminae. ...
Source: Developmental Biology - September 10, 2020 Category: Biology Authors: Kukreja S, Udaykumar N, Yogesh B, Sen J Tags: Dev Biol Source Type: research

A systematic, label-free method for identifying RNA-associated proteins in vivo provides insights into vertebrate ciliary beating machinery.
Abstract Cell-type specific RNA-associated proteins are essential for development and homeostasis in animals. Despite a massive recent effort to systematically identify RNA-associated proteins, we currently have few comprehensive rosters of cell-type specific RNA-associated proteins in vertebrate tissues. Here, we demonstrate the feasibility of determining the RNA-interacting proteome of a defined vertebrate embryonic tissue using DIF-FRAC, a systematic and universal (i.e., label-free) method. Application of DIF-FRAC to cultured tissue explants of Xenopus mucociliary epithelium identified dozens of known RNA-assoc...
Source: Developmental Biology - September 5, 2020 Category: Biology Authors: Drew K, Lee C, Cox RM, Dang V, Devitt CC, McWhite CD, Papoulas O, Huizar RL, Marcotte EM, Wallingford JB Tags: Dev Biol Source Type: research

The multiple roles of caudal in early development of the milkweed bug Oncopeltus fasciatus.
Abstract The homeobox transcription factor Caudal has conserved roles in all Bilateria in defining the posterior pole and in controlling posterior elongation. These roles are seemingly similar and are difficult to disentangle. We have carried out a detailed analysis of the expression, function and interactions of the caudal ortholog of the milkweed bug, Oncopeltus fasciatus, a hemimetabolous insect with a conservative early development process, in order to understand its different functions throughout development. In Oncopeltus, caudal is not maternally deposited, but has a sequence of roles in the posterior of th...
Source: Developmental Biology - September 3, 2020 Category: Biology Authors: Novikova AV, Auman T, Cohen M, Oleynik O, Stahi-Hitin R, Gil E, Weisbrod A, Chipman AD Tags: Dev Biol Source Type: research

Mcrs1 interacts with Six1 to influence early craniofacial and otic development.
Abstract The Six1 transcription factor plays a major role in craniofacial development. Mutations in SIX1 and its co-factor, EYA1, are causative for about 50% of Branchio-otic/Branchio-oto-renal syndrome (BOR) patients, who are characterized by variable craniofacial, otic and renal malformations. We previously screened for other proteins that might interact with Six1 to identify additional genes that may play a role in BOR, and herein characterize the developmental role of one of them, Microspherule protein 1 (Mcrs1). We found that in cultured cells, Mcrs1 bound to Six1 and in both cultured cells and embryonic ecto...
Source: Developmental Biology - September 3, 2020 Category: Biology Authors: Neilson KM, Keer S, Bousquet N, Macrorie O, Majumdar HD, Kenyon KL, Alfandari D, Moody SA Tags: Dev Biol Source Type: research

Nervous system and tissue polarity dynamically adapt to new morphologies in planaria.
Abstract The coordination of tissue-level polarity with organism-level polarity is crucial in development, disease, and regeneration. Here, we characterize a new example of large-scale control of dynamic remodeling of body polarity. Exploiting the flexibility of the body plan in regenerating planarians, we used mirror duplication of the primary axis to show how established tissue-level polarity adapts to new organism-level polarity. Characterization of epithelial planar cell polarity revealed a remarkable reorientation of tissue polarity in double-headed planarians. This reorientation of cilia occurs even followin...
Source: Developmental Biology - August 31, 2020 Category: Biology Authors: Bischof J, Day ME, Miller KA, LaPalme JV, Levin M Tags: Dev Biol Source Type: research

Wnt signaling determines body axis polarity in regenerating hydra tissue.
Abstract How an animal establishes its body axis is a fundamental question in developmental biology. The freshwater cnidarian Hydra is an attractive model for studying axis formation because it is radially symmetric, with a single oral-aboral axis. It was recently proposed that the orientation of the new body axis in a regenerating Hydra polyp is determined by the oral-aboral orientation of the actin-myosin contractile processes (myonemes) in the animal's outer epithelial layer. However, it remained unclear how the oral-aboral polarity of the body axis would be defined. As Wnt signaling is known to control axis po...
Source: Developmental Biology - August 29, 2020 Category: Biology Authors: Wang R, Steele RE, Collins ES Tags: Dev Biol Source Type: research

mTOR plays a pivotal role in multiple processes of enamel organ development principally through the mTORC1 pathway and in part via regulating cytoskeleton dynamics.
Abstract We herein report that deletion of mTOR in dental epithelia caused defective development of multiple cell layers of the enamel organ, which culminated in tooth malformation and cystogenesis. Specifically, cells of the stellate reticulum and stratum intermedium were poorly formed, resulting in cystic change. The pre-ameloblasts failed to elongate along the apical-basal axis and persisted vigorous expression of Sox2 and P63, which are normally downregulated during cytodifferentiation. Expression of amelogenic markers was also attenuated in mutants. Cell proliferation and cell sizes in mutants were significan...
Source: Developmental Biology - August 28, 2020 Category: Biology Authors: Nie X, Zheng J, Cruciger M, Yang P, Mao JJ Tags: Dev Biol Source Type: research

Lens fiber cell differentiation occurs independently of fibroblast growth factor receptor signaling in the absence of Pten.
Abstract Fibroblast growth factor receptor (FGFR) signaling patterns multiple tissues in both vertebrates and invertebrates, largely through the activation of intracellular kinases. Recent studies have demonstrated that the phosphatase, PTEN negatively regulates FGFR signaling, such that the loss of PTEN can compensate for reduced FGFR signaling to rescue aspects of normal development. In the developing mouse lens, FGFR signaling promotes cell survival and fiber cell differentiation, and the loss of Pten largely compensates for the loss of Fgfr2 during lens development. To explore this regulatory relationship furt...
Source: Developmental Biology - August 25, 2020 Category: Biology Authors: Padula SL, Sidler EP, Wagner BD, Manz CJ, Lovicu FJ, Robinson ML Tags: Dev Biol Source Type: research

Migratory patterns and evolutionary plasticity of cranial neural crest cells in ray-finned fishes.
rny R Abstract The cranial neural crest (CNC) arises within the developing central nervous system, but then migrates away from the neural tube in three consecutive streams termed mandibular, hyoid and branchial, respectively, according to the order along the anteroposterior axis. While the process of neural crest emigration generally follows a conserved anterior to posterior sequence across vertebrates, we find that ray-finned fishes (bichir, sterlet, gar, and pike) exhibit several heterochronies in the timing and order of CNC emergence that influences their subsequent migratory patterns. First, emigration of the ...
Source: Developmental Biology - August 21, 2020 Category: Biology Authors: Stundl J, Pospisilova A, Matějková T, Psenicka M, Bronner ME, Cerny R Tags: Dev Biol Source Type: research

Multi-organ transcriptomic landscape of Ambystoma velasci metamorphosis.
Abstract Metamorphosis is a postembryonic developmental process that involves morphophysiological and behavioral changes, allowing organisms to adapt into a novel environment. In some amphibians, aquatic organisms undergo metamorphosis to adapt in a terrestrial environment. In this process, these organisms experience major changes in their circulatory, respiratory, digestive, excretory and reproductive systems. We performed a transcriptional global analysis of heart, lung and gills during diverse stages of Ambystoma velasci to investigate its metamorphosis. In our analyses, we identified eight gene clusters for ea...
Source: Developmental Biology - August 20, 2020 Category: Biology Authors: Janet PM, Juan CP, Annie EC, Gilberto MC, Hilda L, Enrique SV, Denhi S, Jesus CM, Alfredo CR Tags: Dev Biol Source Type: research

Cell culture system to assay candidate genes and molecular pathways implicated in congenital diaphragmatic hernias.
Abstract The mammalian muscularized diaphragm is essential for respiration and defects in the developing diaphragm cause a common and frequently lethal birth defect, congenital diaphragmatic hernia (CDH). Human genetic studies have implicated more than 150 genes and multiple molecular pathways in CDH, but few of these have been validated because of the expense and time to generate mouse mutants. The pleuroperitoneal folds (PPFs) are transient embryonic structures in diaphragm development and defects in PPFs lead to CDH. We have developed a system to culture PPF fibroblasts from E12.5 mouse embryos and show that th...
Source: Developmental Biology - August 19, 2020 Category: Biology Authors: Bogenschutz EL, Sefton EM, Kardon G Tags: Dev Biol Source Type: research

Molecular mechanisms regulating axon responsiveness at the midline.
Abstract During embryonic development in bilaterally symmetric organisms, correct midline crossing is important for the proper formation of functional neural circuits. The aberrant development of neural circuits can result in multiple neurodevelopmental disorders, including horizontal gaze palsy, congenital mirror movement disorder, and autism spectrum disorder. Thus, understanding the molecular mechanisms that regulate proper axon guidance at the midline can provide insights into the pathology of neurological disorders. The signaling mechanisms that regulate midline crossing have been extensively studied in the D...
Source: Developmental Biology - August 17, 2020 Category: Biology Authors: Gorla M, Bashaw GJ Tags: Dev Biol Source Type: research

Corrigendum to "Caspase 9 is constitutively activated in mouse oocytes and plays a key role in oocyte elimination during meiotic prophase progression" [Dev. Biol. Vol.377 (2013) 213-223].
Corrigendum to "Caspase 9 is constitutively activated in mouse oocytes and plays a key role in oocyte elimination during meiotic prophase progression" [Dev. Biol. Vol.377 (2013) 213-223]. Dev Biol. 2020 Aug 13;: Authors: Ene AC, Park S, Edelmann W, Taketo T PMID: 32800616 [PubMed - as supplied by publisher] (Source: Developmental Biology)
Source: Developmental Biology - August 13, 2020 Category: Biology Authors: Ene AC, Park S, Edelmann W, Taketo T Tags: Dev Biol Source Type: research

Foxi1 inactivation rescues loss of principal cell fate selection in Hes1-deficient kidneys but does not ensure maintenance of principal cell gene expression.
Abstract The distal nephron and collecting duct segments of the mammalian kidney consist of intercalated cell types intermingled among principal cell types. Notch signaling ensures that a sufficient number of cells select a principal instead of an intercalated cell fate. However, the precise mechanisms by which Notch signaling patterns the distal nephron and collecting duct cell fates is unknown. Here we observed that Hes1, a direct target of Notch signaling pathway, is required within the mouse developing collecting ducts for repression of Foxi1 expression, an essential intercalated cell specific transcription fa...
Source: Developmental Biology - August 12, 2020 Category: Biology Authors: Mukherjee M, DeRiso J, Janga M, Fogarty E, Surendran K Tags: Dev Biol Source Type: research

Pdgfra regulates multipotent cell differentiation towards chondrocytes via inhibiting Wnt9a/beta-catenin pathway during chondrocranial cartilage development.
Abstract The mammalian skull is composed of the calvarial bones and cartilages. Malformation of craniofacial cartilage has been identified in multiple human syndromes. However, the mechanisms of their development remain largely unknown. In the present study, we identified Pdgfra as a novel player of chondrocranial cartilage development. Our data show that Pdgfra is required for normal chondrocranial cartilage development. Using tissue-specific genetic tools, we demonstrated that Pdgfra is essential for chondrocyte progenitors formation, but not in mature chondrocytes. Further analysis revealed that Pdgfra regulate...
Source: Developmental Biology - August 12, 2020 Category: Biology Authors: Bartoletti G, Dong C, Umar M, He F Tags: Dev Biol Source Type: research

Development and regeneration of the crushing dentition in skates (Rajidae).
Abstract Sharks and rays (elasmobranchs) have the remarkable capacity to continuously regenerate their teeth. The polyphyodont system is considered the ancestral condition of the gnathostome dentition. Despite this shared regenerative ability, sharks and rays exhibit dramatic interspecific variation in their tooth morphology. Ray (batoidea) teeth typically constitute crushing pads of flattened teeth, whereas shark teeth are pointed, multi-cuspid units. Although recent research has addressed the molecular development of the shark dentition, little is known about that of the ray. Furthermore, how dental diversity wi...
Source: Developmental Biology - August 10, 2020 Category: Biology Authors: Rasch LJ, Cooper RL, Underwood C, Dillard WA, Thiery AP, Fraser GJ Tags: Dev Biol Source Type: research

Drainage of amniotic fluid delays vocal fold separation and induces load-related vocal fold mucosa remodeling.
Abstract In the present study, we investigated the role of mechanical load as generated by amniotic fluid in the vocal fold embryogenesis. In utero, amniotic fluid flows through the laryngeal inlet down into the lungs during fetal breathing and swallowing. In a mouse model, the onset of fetal breathing coincides with epithelial lamina recanalization. The epithelial lamina is a temporal structure that is formed during early stages of the larynx development and is gradually resorbed whereby joining the upper and lower airways. Here, we show that a temporary decrease in mechanical load secondary to drainage of amniot...
Source: Developmental Biology - August 7, 2020 Category: Biology Authors: Lungova V, Griffin KV, Lunga T, Thibeault SL Tags: Dev Biol Source Type: research

Development and patterning of rib primordia are dependent on associated musculature.
In this study, we utilize both gene knockouts and muscle cell ablation approaches to re-visit the extent to which rib growth and patterning are dependent on developing musculature. Consistent with previous studies, we show that rib formation is highly dependent on the MYOD family of myogenic regulatory factors (MRFs), and demonstrate that the extent of rib formation is gene-, allele-, and dosage-dependent. In the absence of Myf5 and MyoD, one allele of Mrf4 is sufficient for extensive rib growth, although patterning is abnormal. Under conditions of limiting MRF dosage, MyoD is identified as a positive regulator of rib patt...
Source: Developmental Biology - August 5, 2020 Category: Biology Authors: Wood WM, Otis C, Etemad S, Goldhamer DJ Tags: Dev Biol Source Type: research

Low-cost and efficient confocal imaging method for arabidopsis flower.
Abstract For an extensive period of time apical meristem (SAM) has been considered as a mysterious organ, due to its small, hidden and dynamic structure. Confocal imaging, combined with fluorescent reporters, enables researchers to unveil the mechanisms underlying cellular activities, such as gene expression, cell division, growth patterns and cell-cell communications. Recently, a series of protocols were developed for confocal imaging of inflorescence meristem (IM) and floral meristem (FM). However, the requirement of high configuration, such as the need of a water-dipping lens without coverslip and the specializ...
Source: Developmental Biology - August 4, 2020 Category: Biology Authors: Wei J, Qi Y, Li M, Li R, Yan M, Shen H, Tian L, Liu Y, Tian S, Liu L, Zhang Y, Sun H, Bai Z, Zhang K, Li C Tags: Dev Biol Source Type: research

Keratin 13 deficiency causes white sponge nevus in mice.
Abstract White sponge nevus (WSN) is a benign autosomal dominant disorder characterized by the formation of white spongy plaques in the oral mucosa. Keratin (KRT) 13 is highly expressed in the mucosa, and mutations in this gene have been commonly associated with WSN patients. However, it remains unknown whether there is a causal relationship between KRT13 mutations and WSN and what the underlying mechanisms might be. Here, we use mouse genetic models to demonstrate that Krt13 is crucial for the maintenance of epithelial integrity. Krt13 knockout mice show a WSN-like phenotype in several tissues, including the tong...
Source: Developmental Biology - August 3, 2020 Category: Biology Authors: Simonson L, Vold S, Mowers C, Massey RJ, Ong IM, Longley BJ, Chang H Tags: Dev Biol Source Type: research

In vivo analysis of the evolutionary conserved BTD-box domain of Sp1 and Btd during Drosophila development.
, Estella C Abstract The Sp family of transcription factors plays important functions during development and disease. An evolutionary conserved role for some Sp family members is the control of limb development. The family is characterized by the presence of three C2H2-type zinc fingers and an adjacent 10 aa region with an unknown function called the Buttonhead (BTD) box. The presence of this BTD-box in all Sp family members identified from arthropods to vertebrates, suggests that it plays an essential role during development. However, despite its conservation, the in vivo function of the BTD-box has never been st...
Source: Developmental Biology - July 29, 2020 Category: Biology Authors: Blom-Dahl D, Córdoba S, Gabilondo H, Carr-Baena P, Díaz-Benjumea FJ, Estella C Tags: Dev Biol Source Type: research

Conservation as well as divergence in Mcidas function underlies the differentiation of multiciliated cells in vertebrates.
Abstract Multiciliated cells (MCCs) differentiate hundreds of motile cilia that beat to drive fluid movement over various kinds of epithelia. In Xenopus, mice and human, the coiled-coil containing protein Mcidas (Mci) has been shown to be a key transcriptional regulator of MCC differentiation. We have examined Mci function in the zebrafish, another model organism that is widely used to study ciliary biology. We show that zebrafish mci is expressed specifically in the developing MCCs of the kidney tubules, but surprisingly, not in those of the nasal placodes. Mci proteins lack a DNA binding domain and associate wit...
Source: Developmental Biology - July 28, 2020 Category: Biology Authors: Zhou F, Rayamajhi D, Ravi V, Narasimhan V, Chong YL, Lu H, Venkatesh B, Roy S Tags: Dev Biol Source Type: research

Histone methyltransferase activity programs nuclear peripheral genome positioning.
Abstract Spatial organization of the genome in the nucleus plays a critical role in development and regulation of transcription. A genomic region that resides at the nuclear periphery is part of the chromatin layer marked with histone H3 lysine 9 dimethyl (H3K9me2), but chromatin reorganization during cell differentiation can cause movement in and out of this nuclear compartment with patterns specific for individual cell fates. Here we describe a CRISPR-based system that allows visualization coupled with forced spatial relocalization of a target genomic locus in live cells. We demonstrate that a specified locus ca...
Source: Developmental Biology - July 23, 2020 Category: Biology Authors: See K, Kiseleva AA, Smith CL, Liu F, Li J, Poleshko A, Epstein JA Tags: Dev Biol Source Type: research

CRISPR/Cas9-mediated mutation reveals Pax6 is essential for development of the compound eye in Decapoda Exopalaemon carinicauda.
Abstract The compound eye in crustaceans is a main eye type in the animal kingdom, knowledge about the mechanism to determine the development of compound eye is very limited. Paired box protein 6 (Pax6) is generally regarded as a master regulator for eye development. In the present study, a genome-based analysis of the Pax6 gene in the ridge tail white prawn Exopalaemon carinicauda was performed and two members of Pax6 homologs, named Ec-Eyeless (EcEy) and Ec-Twin of eyeless (EcToy) were identified. To understand the function of these two homologs of Pax6 gene in the prawn, the CRISPR/Cas9 genome editing technique...
Source: Developmental Biology - July 20, 2020 Category: Biology Authors: Gao Y, Zhang X, Zhang X, Yuan J, Xiang J, Li F Tags: Dev Biol Source Type: research

Orchestration of the distinct morphogenetic movements in different tissues drives tail regression during ascidian metamorphosis.
This study investigated the cellular and molecular mechanisms underlying this metamorphic event called tail regression, in the model ascidian Ciona. The ascidian tail consists of internal organs such as muscle, notochord, nerve cord, and the outer epidermal layer surrounding them. We found that the epidermis and internal organs show different regression strategies. Epidermal cells are shortened along the anterior-posterior axis and gather at the posterior region. The epidermal mass is then invaginated into the trunk by apical constriction. The internal tissues, by contrast, enter into the trunk by forming coils. During coi...
Source: Developmental Biology - July 19, 2020 Category: Biology Authors: Yamaji S, Hozumi A, Matsunobu S, Sasakura Y Tags: Dev Biol Source Type: research

An optimized QF-binary expression system for use in zebrafish.
Abstract The zebrafish model organism has been of exceptional utility for the study of vertebrate development and disease through the application of tissue-specific labelling and overexpression of genes carrying patient-derived mutations. However, there remains a need for a binary expression system that is both non-toxic and not silenced over animal generations by DNA methylation. The Q binary expression system derived from the fungus Neurospora crassa is ideal, because the consensus binding site for the QF transcription factor lacks CpG dinucleotides, precluding silencing by CpG-meditated methylation. To optimize...
Source: Developmental Biology - July 19, 2020 Category: Biology Authors: Burgess J, Burrows JT, Sadhak R, Chiang S, Weiss A, D'Amata C, Molinaro AM, Zhu S, Long M, Hu C, Krause HM, Pearson BJ Tags: Dev Biol Source Type: research

Periocular neural crest cell differentiation into corneal endothelium is influenced by signals in the nascent corneal environment.
This study focuses on the corneal endothelium, a monolayer of specialized cells that are essential for maintaining normal hydration and transparency of the cornea. In avians, corneal endothelial cells are first to be specified from the pNC during their migration into the presumptive corneal region. To investigate the signals required for formation of the corneal endothelium, we utilized orthotopic and heterotopic injections of dissociated quail pNC into chick ocular regions. We find that pNC are multipotent and that the nascent cornea is competent to induce differentiation of ectopically injected pNC into corneal endotheli...
Source: Developmental Biology - July 19, 2020 Category: Biology Authors: Babushkina A, Lwigale P Tags: Dev Biol Source Type: research

Mosaic Analysis with Double Markers reveals IGF1R function in granule cell progenitors during cerebellar development.
Abstract During cerebellar development, granule cell progenitors (GCPs) proliferate exponentially for a fixed period, promoted by paracrine mitogenic factor Sonic Hedgehog (Shh) secreted from Purkinje cells (PCs). Dysregulation of Shh signaling leads to uncontrolled GCP proliferation and medulloblastoma. Serendipitously our previous work discovered insulin-like growth factor 1 (IGF1) as another key driver for medulloblastoma, which led to the current investigation into the role of IGF1 in GCPs during normal development. While the IGF1R conditional knockout model revealed GCP defects in anterior cerebellum, the pos...
Source: Developmental Biology - July 19, 2020 Category: Biology Authors: Terry TT, Cheng T, Mahjoub M, Zong H Tags: Dev Biol Source Type: research

OFCD syndrome and extraembryonic defects are revealed by conditional mutation of the polycomb-group repressive complex 1.1 (PRC1.1) gene BCOR.
Abstract BCOR is a critical regulator of human development. Heterozygous mutations of BCOR in females cause the X-linked developmental disorder Oculofaciocardiodental syndrome (OFCD), and hemizygous mutations of BCOR in males cause gestational lethality. BCOR associates with Polycomb group proteins to form one subfamily of the diverse Polycomb repressive complex 1 (PRC1) complexes, designated PRC1.1. Currently there is limited understanding of differing developmental roles of the various PRC1 complexes. We therefore generated a conditional exon 9-10 knockout Bcor allele and a transgenic conditional Bcor expression...
Source: Developmental Biology - July 18, 2020 Category: Biology Authors: Hamline MY, Corcoran CM, Wamstad JA, Miletich I, Feng J, Lohr JL, Hemberger M, Sharpe PT, Gearhart MD, Bardwell VJ Tags: Dev Biol Source Type: research

Development of the electric organ in embryos and larvae of the knifefish, Brachyhypopomus gauderio.
Abstract South American Gymnotiform knifefish possess electric organs that generate electric fields for electro-location and electro-communication. Electric organs in fish can be derived from either myogenic cells (myogenic electric organ/mEO) or neurogenic cells (neurogenic electric organ/nEO). To date, the embryonic development of EOs has remained obscure. Here we characterize the development of the mEO in the Gymnotiform bluntnose knifefish, Brachyhypopomus gauderio. We find that EO primordial cells arise during embryonic stages in the ventral edge of the tail myotome, translocate into the ventral fin and devel...
Source: Developmental Biology - July 17, 2020 Category: Biology Authors: Alshami IJJ, Ono Y, Correia A, Hacker C, Lange A, Scholpp S, Kawasaki M, Ingham PW, Kudoh T Tags: Dev Biol Source Type: research

Neurons survive simultaneous injury to axons and dendrites and regrow both types of processes in vivo.
Abstract Neurons extend dendrites and axons to receive and send signals. If either type of process is removed, the cell cannot function. Rather than undergoing cell death, some neurons can regrow axons and dendrites. Axon and dendrite regeneration have been examined separately and require sensing the injury and reinitiating the correct growth program. Whether neurons in vivo can sense and respond to simultaneous axon and dendrite injury with polarized regeneration has not been explored. To investigate the outcome of simultaneous axon and dendrite damage, we used a Drosophila model system in which neuronal polarity...
Source: Developmental Biology - July 17, 2020 Category: Biology Authors: Shorey M, Stone MC, Mandel J, Rolls MM Tags: Dev Biol Source Type: research

Diversity of activator of G-Protein signaling (AGS)-family proteins and their impact on asymmetric cell division across taxa.
Abstract Asymmetric cell division (ACD) is a cellular process that forms two different cell types through a cell division and is thus critical for the development of all multicellular organisms. Not all but many of the ACD processes are mediated by proper orientation of the mitotic spindle, which segregates the fate determinants asymmetrically into daughter cells. In many cell types, the evolutionarily conserved protein complex of Gαi/AGS-family protein/NuMA-like protein appears to play critical roles in orienting the spindle and/or generating the polarized cortical forces to regulate ACD. Studies in various...
Source: Developmental Biology - July 17, 2020 Category: Biology Authors: Wavreil FDM, Yajima M Tags: Dev Biol Source Type: research

A pair-rule function of odd-skipped in germband stages of Tribolium development.
Abstract While pair-rule patterning has been observed in most insects examined, the orthologs of Drosophila pair-rule genes have shown divergent roles in insect segmentation. In the beetle Tribolium castaneum, while odd-skipped (Tc-odd) was expressed as a series of pair-rule stripes, RNAi-mediated knockdown of Tc-odd (Tc-oddRNAi) resulted in severely truncated, almost asegmental phenotypes rather than the classical pair-rule phenotypes observed in germbands and larval cuticles. However, considering that most segments arise later in germband stages of Tribolium development, the roles of Tc-odd in segmentation of gr...
Source: Developmental Biology - July 17, 2020 Category: Biology Authors: Jeon H, Gim S, Na H, Choe CP Tags: Dev Biol Source Type: research

Conjugated activation of myocardial-specific transcription of Gja5 by a pair of Nkx2-5-Shox2 co-responsive elements.
Abstract The sinoatrial node (SAN) is the primary pacemaker in the heart. During cardiogenesis, Shox2 and Nkx2-5 are co-expressed in the junction domain of the SAN and regulate pacemaker cell fate through a Shox2-Nkx2-5 antagonism. Cx40 is a marker of working myocardium and an Nkx2-5 transcriptional output antagonized by Shox2, but the underlying regulatory mechanisms remain elusive. Here we characterized a bona fide myocardial-specific Gja5 (coding gene of Cx40) distal enhancer consisting of a pair of Nkx2-5 and Shox2 co-bound elements in the regulatory region of Gja5. Transgenic reporter assays revealed that nei...
Source: Developmental Biology - July 17, 2020 Category: Biology Authors: Yang T, Huang Z, Li H, Wang L, Chen Y Tags: Dev Biol Source Type: research

Foxa1 and Foxa2 orchestrate development of the urethral tube and division of the embryonic cloaca through an autoregulatory loop with Shh.
Abstract Congenital anomalies of external genitalia affect approximately 1 in 125 live male births. Development of the genital tubercle, the precursor of the penis and clitoris, is regulated by the urethral plate epithelium, an endodermal signaling center. Signaling activity of the urethral plate is mediated by Sonic hedgehog (SHH), which coordinates outgrowth and patterning of the genital tubercle by controlling cell cycle kinetics and expression of downstream genes. The mechanisms that govern Shh transcription in urethral plate cells are largely unknown. Here we show that deletion of Foxa1 and Foxa2 results in p...
Source: Developmental Biology - July 6, 2020 Category: Biology Authors: Gredler ML, Patterson SE, Seifert AW, Cohn MJ Tags: Dev Biol Source Type: research

Developmental origins of transgenerational sperm histone retention following ancestral exposures.
Abstract Numerous environmental toxicants have been shown to induce the epigenetic transgenerational inheritance of disease and phenotypic variation. Alterations in the germline epigenome are necessary to transmit transgenerational phenotypes. In previous studies, the pesticide DDT (dichlorodiphenyltrichloroethane) and the agricultural fungicide vinclozolin were shown to promote the transgenerational inheritance of sperm differential DNA methylation regions, non-coding RNAs and histone retention, which are termed epimutations. These epimutations are able to mediate this epigenetic inheritance of disease and phenot...
Source: Developmental Biology - July 3, 2020 Category: Biology Authors: Ben Maamar M, Beck D, Nilsson E, McCarrey JR, Skinner MK Tags: Dev Biol Source Type: research

Protein phosphatase 1 regulatory subunit 35 is required for ciliogenesis, notochord morphogenesis, and cell-cycle progression during murine development.
Abstract Protein phosphatases regulate a wide array of proteins through post-translational modification and are required for a plethora of intracellular events in eukaryotes. While some core components of the protein phosphatase complexes are well characterized, many subunits of these large complexes remain unstudied. Here we characterize a loss-of-function allele of the protein phosphatase 1 regulatory subunit 35 (Ppp1r35) gene. Homozygous mouse embryos lacking Ppp1r35 are developmental delayed beginning at embryonic day (E) 7.5 and have obvious morphological defects at later stages. Mutants fail to initiate turn...
Source: Developmental Biology - July 3, 2020 Category: Biology Authors: Archambault D, Cheong A, Iverson E, Tremblay KD, Mager J Tags: Dev Biol Source Type: research

Ets1 functions partially redundantly with Etv2 to promote embryonic vasculogenesis and angiogenesis in zebrafish.
Abstract ETS transcription factors play an important role in the specification and differentiation of endothelial cells during vascular development. Despite previous studies, the role of the founding member of the ETS family, Ets1, in vascular development in vivo is only partially understood. Here, we generated a zebrafish ets1 mutant by TALEN genome editing and tested functional redundancy between Ets1 and a related ETS factor Etv2/Etsrp/ER71. While zebrafish ets1-/- mutants have a normal functional vascular system, etv2-/-;ets1-/embryos had more severe angiogenic defects and lower expression levels of kdr and kd...
Source: Developmental Biology - July 3, 2020 Category: Biology Authors: Chetty SC, Sumanas S Tags: Dev Biol Source Type: research

Integrin α5 and Integrin α4 cooperate to promote endocardial differentiation and heart morphogenesis.
Integrin α5 and Integrin α4 cooperate to promote endocardial differentiation and heart morphogenesis. Dev Biol. 2020 Jul 03;: Authors: Schumacher JA, Wright ZA, Owen M, Bredemeier NO, Sumanas S Abstract Endocardium is critically important for proper function of the cardiovascular system. Not only does endocardium connect the heart to blood vasculature, it also plays an important role in heart morphogenesis, valve formation, and ventricular trabeculation. The extracellular protein Fibronectin (Fn1) promotes endocardial differentiation, but the signaling pathways downstream of Fn1 that regul...
Source: Developmental Biology - July 3, 2020 Category: Biology Authors: Schumacher JA, Wright ZA, Owen M, Bredemeier NO, Sumanas S Tags: Dev Biol Source Type: research

Deletion of the Dishevelled family of genes disrupts anterior-posterior axis specification and selectively prevents mesoderm differentiation.
Abstract The Dishevelled proteins transduce both canonical Wnt/β-catenin and non-canonical Wnt/planar cell polarity (PCP) signaling pathways to regulate many key developmental processes during embryogenesis. Here, we disrupt both canonical and non-canonical Wnt pathways by targeting the entire Dishevelled family of genes (Dvl1, Dvl2, and Dvl3) to investigate their functional roles in the early embryo. We identified several defects in anterior-posterior axis specification and mesoderm patterning in Dvl1+/-; Dvl2-/-; Dvl3-/- embryos. Homozygous deletions in all three Dvl genes (Dvl TKO) resulted in defects in d...
Source: Developmental Biology - June 21, 2020 Category: Biology Authors: Ngo J, Hashimoto M, Hamada H, Wynshaw-Boris A Tags: Dev Biol Source Type: research

Macrophages fine-tune pupil shape during development.
Abstract Tissue macrophages, which are ubiquitously present innate immune cells, play versatile roles in development and organogenesis. During development, macrophages prune transient or unnecessary synapses in neuronal development, and prune blood vessels in vascular development, facilitating appropriate tissue remodeling. In the present study, we identified that macrophages contributed to the development of pupillary morphology. Csf1op/op mutant mice, in which ocular macrophages are nearly absent, exhibited abnormal pupillary edges, with abnormal protrusions of excess iris tissue into the pupillary space. Macrop...
Source: Developmental Biology - June 18, 2020 Category: Biology Authors: Takahashi M, Misaki M, Shibata S, Iga T, Shindo T, Tai-Nagara I, Hirata A, Ogawa M, Miyamoto T, Nakagawa T, Ema M, Ichiyama Y, Shima DT, Hozumi K, Nishimura S, Kubota Y Tags: Dev Biol Source Type: research

Prdm1 overexpression causes a photoreceptor fate-shift in nascent, but not mature, bipolar cells.
Abstract The transcription factors Prdm1 (Blimp1) and Vsx2 (Chx10) work downstream of Otx2 to regulate photoreceptor and bipolar cell fates in the developing retina. Mice that lack Vsx2 fail to form bipolar cells while Prdm1 mutants form excess bipolars at the direct expense of photoreceptors. Excess bipolars in Prdm1 mutants appear to derive from rods, suggesting that photoreceptor fate remains mutable for some time after cells become specified. Here we tested whether bipolar cell fate is also plastic during development. To do this, we created a system to conditionally misexpress Prdm1 at different stages of bipo...
Source: Developmental Biology - June 17, 2020 Category: Biology Authors: Goodson NB, Park KU, Silver JS, Chiodo VA, Hauswirth WW, Brzezinski JA Tags: Dev Biol Source Type: research

ROBO2-mediated RALDH2 signaling is required for common nephric duct fusion with primitive bladder.
Abstract Congenital anomalies of the urinary tract are a significant cause of morbidity in infancy, and many congenital anomalies are linked to ureter development; however, the mechanism by which congenital anomalies control ureter development remains unknown. The loss of Robo2 can cause ureter defects and vesicoureteral reflux. However, how Robo2 impacts ureter development is unclear. We found that ROBO2 is expressed in the common nephric duct (CND) and primitive bladder, and impacts CND migration and fusion with the primitive bladder via its novel binding partner retinaldehyde dehydrogenase-2 (RALDH2). Delayed a...
Source: Developmental Biology - June 17, 2020 Category: Biology Authors: Li Q, Ji J, Cui S, Liu Y, Ma Q, Fu B, Yang J, Xiao Y, Bai X, Cai G, Xie Y, Chen X Tags: Dev Biol Source Type: research

Rab11 is essential for lgl mediated JNK-Dpp signaling in dorsal closure and epithelial morphogenesis in Drosophila.
Abstract Dorsal closure during Drosophila embryogenesis provides a robust genetic platform to study the basic cellular mechanisms that govern epithelial wound healing and morphogenesis. As dorsal closure proceeds, the lateral epithelial tissue (LE) adjacent to the dorsal opening advance contra-laterally, with a simultaneous retraction of the amnioserosa. The process involves a fair degree of coordinated cell shape changes in the dorsal most epithelial (DME) cells as well as a few penultimate rows of lateral epithelial (LE) cells (collectively referred here as Dorsolateral Epithelial (DLE) cells), lining the periph...
Source: Developmental Biology - June 17, 2020 Category: Biology Authors: Nandy N, Roy JK Tags: Dev Biol Source Type: research