Phylodynamics for cell biologists
Multicellular organisms are composed of cells connected by ancestry and descent from progenitor cells. The dynamics of cell birth, death, and inheritance within an organism give rise to the fundamental processes of development, differentiation, and cancer. Technical advances in molecular biology now allow us to study cellular composition, ancestry, and evolution at the resolution of individual cells within an organism or tissue. Here, we take a phylogenetic and phylodynamic approach to single-cell biology. We explain how "tree thinking" is important to the interpretation of the growing body of cell-level data and how ecolo...
Source: ScienceNOW - January 14, 2021 Category: Science Authors: Stadler, T., Pybus, O. G., Stumpf, M. P. H. Tags: Cell Biology, Online Only review Source Type: news

Max Planck Society, Rockefeller University Press enter " read-and-publish " agreement
(Rockefeller University Press) Max Planck Digital Library (MPDL) has signed an unlimited " read-and-publish " transformative agreement with Rockefeller University Press (RUP) on behalf of the Max Planck Society. The agreement covers Open Access (OA) publishing of articles in RUP's three hybrid journals:Journal of Cell Biology (JCB),Journal of Experimental Medicine (JEM) andJournal of General Physiology (JGP). (Source: EurekAlert! - Medicine and Health)
Source: EurekAlert! - Medicine and Health - January 13, 2021 Category: International Medicine & Public Health Source Type: news

Tubulin glycylation controls axonemal dynein activity, flagellar beat, and male fertility
In this study, we generated a mouse model entirely lacking tubulin glycylation. Male mice were subfertile owing to aberrant beat patterns of their sperm flagella, which impeded the straight swimming of sperm cells. Using cryo–electron tomography, we showed that lack of glycylation caused abnormal conformations of the dynein arms within sperm axonemes, providing the structural basis for the observed dysfunction. Our findings reveal the importance of microtubule glycylation for controlled flagellar beating, directional sperm swimming, and male fertility. (Source: ScienceNOW)
Source: ScienceNOW - January 7, 2021 Category: Science Authors: Gadadhar, S., Alvarez Viar, G., Hansen, J. N., Gong, A., Kostarev, A., Ialy-Radio, C., Leboucher, S., Whitfield, M., Ziyyat, A., Toure, A., Alvarez, L., Pigino, G., Janke, C. Tags: Biochemistry, Cell Biology, Online Only r-articles Source Type: news

Glycylation regulates axonemal dyneins
(Source: ScienceNOW)
Source: ScienceNOW - January 7, 2021 Category: Science Authors: Hurtley, S. M. Tags: Biochemistry, Cell Biology twis Source Type: news

Gene therapy beats premature-aging syndrome in mice
(Source: ScienceNOW)
Source: ScienceNOW - January 7, 2021 Category: Science Authors: Kaiser, J. Tags: Cell Biology, Genetics, Medicine, Diseases In Depth Source Type: news

Decoy toxin harnessed to fight botulism
(Source: ScienceNOW)
Source: ScienceNOW - January 7, 2021 Category: Science Authors: Servick, K. Tags: Cell Biology, Medicine, Diseases In Depth Source Type: news

Wait for me: Cell biologists decipher signal that ensures no chromosome is left behind
(University of California - San Diego) UC San Diego cell biologists have found a key clue in the mystery of how chromosomes are inherited correctly every time a cell divides. Using a novel cell probe, they unraveled how a 'matchmaker' molecule stops cell division until components are ready to be split. Precise chromosome duplication is a key factor in proper cell division. If components are altered, even slightly, birth defects and certain cancers can result. (Source: EurekAlert! - Medicine and Health)
Source: EurekAlert! - Medicine and Health - January 6, 2021 Category: International Medicine & Public Health Source Type: news

Langer awarded prestigious PRAT fellowship
NIEHS trainee Lee Langer won a Postdoctoral Research Associate (PRAT) Program fellowship to further his studies in stem cell biology. (read more) (Source: Environmental Factor - NIEHS Newsletter)
Source: Environmental Factor - NIEHS Newsletter - January 6, 2021 Category: Environmental Health Source Type: news

QRICH1 dictates the outcome of ER stress through transcriptional control of proteostasis
Tissue homeostasis is perturbed in a diversity of inflammatory pathologies. These changes can elicit endoplasmic reticulum (ER) stress, protein misfolding, and cell death. ER stress triggers the unfolded protein response (UPR), which can promote recovery of ER proteostasis and cell survival or trigger programmed cell death. Here, we leveraged single-cell RNA sequencing to define dynamic transcriptional states associated with the adaptive versus terminal UPR in the mouse intestinal epithelium. We integrated these transcriptional programs with genome-scale CRISPR screening to dissect the UPR pathway functionally. We identifi...
Source: ScienceNOW - December 31, 2020 Category: Science Authors: You, K., Wang, L., Chou, C.-H., Liu, K., Nakata, T., Jaiswal, A., Yao, J., Lefkovith, A., Omar, A., Perrigoue, J. G., Towne, J. E., Regev, A., Graham, D. B., Xavier, R. J. Tags: Cell Biology, Medicine, Diseases, Online Only r-articles Source Type: news

CDC20 assists its catalytic incorporation in the mitotic checkpoint complex
Open (O) and closed (C) topologies of HORMA-domain proteins are respectively associated with inactive and active states of fundamental cellular pathways. The HORMA protein O-MAD2 converts to C-MAD2 upon binding CDC20. This is rate limiting for assembly of the mitotic checkpoint complex (MCC), the effector of a checkpoint required for mitotic fidelity. A catalyst assembled at kinetochores accelerates MAD2:CDC20 association through a poorly understood mechanism. Using a reconstituted SAC system, we discovered that CDC20 is an impervious substrate for which access to MAD2 requires simultaneous docking on several sites of the ...
Source: ScienceNOW - December 31, 2020 Category: Science Authors: Piano, V., Alex, A., Stege, P., Maffini, S., Stoppiello, G. A., Huis in t Veld, P. J., Vetter, I. R., Musacchio, A. Tags: Biochemistry, Cell Biology reports Source Type: news

A tripartite mechanism catalyzes Mad2-Cdc20 assembly at unattached kinetochores
During cell division, kinetochores couple chromosomes to spindle microtubules. To protect against chromosome gain or loss, kinetochores lacking microtubule attachment locally catalyze association of the checkpoint proteins Cdc20 and Mad2, which is the key event in the formation of a diffusible checkpoint complex that prevents mitotic exit. We elucidated the mechanism of kinetochore-catalyzed Mad2-Cdc20 assembly with a probe that specifically monitors this assembly reaction at kinetochores in living cells. We found that catalysis occurs through a tripartite mechanism that includes localized delivery of Mad2 and Cdc20 substr...
Source: ScienceNOW - December 31, 2020 Category: Science Authors: Lara-Gonzalez, P., Kim, T., Oegema, K., Corbett, K., Desai, A. Tags: Biochemistry, Cell Biology reports Source Type: news

Interactions between nascent proteins translated by adjacent ribosomes drive homomer assembly
In this study, we investigated whether direct interaction of two nascent proteins, emerging from nearby ribosomes (co-co assembly), constitutes a general mechanism for oligomer formation. We used proteome-wide screening to detect nascent chain–connected ribosome pairs and identified hundreds of homomer subunits that co-co assemble in human cells. Interactions are mediated by five major domain classes, among which N-terminal coiled coils are the most prevalent. We were able to reconstitute co-co assembly of nuclear lamin in Escherichia coli, demonstrating that dimer formation is independent of dedicated assembly machi...
Source: ScienceNOW - December 31, 2020 Category: Science Authors: Bertolini, M., Fenzl, K., Kats, I., Wruck, F., Tippmann, F., Schmitt, J., Auburger, J. J., Tans, S., Bukau, B., Kramer, G. Tags: Cell Biology, Molecular Biology r-articles Source Type: news

Airway stem cells sense hypoxia and differentiate into protective solitary neuroendocrine cells
Neuroendocrine (NE) cells are epithelial cells that possess many of the characteristics of neurons, including the presence of secretory vesicles and the ability to sense environmental stimuli. The normal physiologic functions of solitary airway NE cells remain a mystery. We show that mouse and human airway basal stem cells sense hypoxia. Hypoxia triggers the direct differentiation of these stem cells into solitary NE cells. Ablation of these solitary NE cells during hypoxia results in increased epithelial injury, whereas the administration of the NE cell peptide CGRP rescues this excess damage. Thus, we identify stem cells...
Source: ScienceNOW - December 31, 2020 Category: Science Authors: Shivaraju, M., Chitta, U. K., Grange, R. M. H., Jain, I. H., Capen, D., Liao, L., Xu, J., Ichinose, F., Zapol, W. M., Mootha, V. K., Rajagopal, J. Tags: Cell Biology, Molecular Biology r-articles Source Type: news

Protecting the lung from hypoxic stress
(Source: ScienceNOW)
Source: ScienceNOW - December 31, 2020 Category: Science Authors: Purnell, B. A. Tags: Cell Biology, Molecular Biology twis Source Type: news

Transcriptional control of proteostasis
(Source: ScienceNOW)
Source: ScienceNOW - December 31, 2020 Category: Science Authors: Hurtley, S. M. Tags: Cell Biology, Medicine, Diseases twis Source Type: news