Redundant regulation of localization and protein stability of DmPar3.
Redundant regulation of localization and protein stability of DmPar3.
Cell Mol Life Sci. 2018 Mar 10;:
Authors: Kullmann L, Krahn MP
Abstract
Apical-basal polarity is an important characteristic of epithelia and Drosophila neural stem cells. The conserved Par complex, which consists of the atypical protein kinase C and the scaffold proteins Baz and Par6, is a key player in the establishment of apical-basal cell polarity. Membrane recruitment of Baz has been reported to be accomplished by several mechanisms, which might function in redundancy, to ensure the correct localization of the complex. However, none of the described interactions was sufficient to displace the protein from the apical junctions. Here, we dissected the role of the oligomerization domain and the lipid-binding motif of Baz in vivo in the Drosophila embryo. We found that these domains function in redundancy to ensure the apical junctional localization of Baz: inactivation of only one domain is not sufficient to disrupt the function of Baz during apical-basal polarization of epithelial cells and neural stem cells. In contrast, mutation of both domains results in a strongly impaired protein stability and a phenotype characterized by embryonic lethality and an impaired apical-basal polarity in the embryonic epithelium and neural stem cells, resembling a baz-loss of function allele. Strikingly, the binding of Baz to the transmembrane proteins E-Cadherin, Echinoid, and S...
Source: Cellular and Molecular Life Sciences : CMLS - Category: Cytology Authors: Kullmann L, Krahn MP Tags: Cell Mol Life Sci Source Type: research