Biology subjects

Kamacioglu, A.

Publications and source records attributed to Kamacioglu, A..

4 recordsLinked to original sources

bioRxiv2021

PCDH7 Promotes Cell Migration by Regulating Myosin Activity

Cell migration requires spatiotemporally coordinated activities of multicomponent structures including the actomyosin cortex, plasma membrane, adhesion complexes and the polarity proteins. How they function together to drive this complex dynamic process remains an outstanding question. Here, we show that a member of the protocadherin family, PCDH7 displays a polarized localization in migratory cells with a dynamic enrichment at the leading and rear edges. Perturbation of PCDH7 interferes with the migration of nontransformed retinal pigment epithelial cells and the invasion of cancer cells. The overexpression of PCDH7 enhances the migration capability of cortical neurons in vivo. PCDH7 interacts with the myosin phosphatase subunits MYPT1 and PP1c{beta}. Ectopic expression of PCDH7 enhances the MYPT1 inhibitory phosphorylation levels and the phosphorylation of the myosin regulatory light chain and ERM at the polarized cortex. The chemical inhibition of phosphatase activity recovers migration phenotypes of PCDH7 knockout cells. We propose that PCDH7 regulates phosphorylation thus the activity of myosin and ERM at the polarized cortex through its interaction with myosin phosphatase. Collectively, our study suggests a new component for the spatial coordination of the plasma membrane and the cortex during cell migration.

cell biology↗

bioRxiv2020

Protocadherin 7 localizes to the plasma membrane during mitosis and promotes cytokinesis by a palmitoylation-dependent mechanism

Cell division requires dramatic reorganization of the cell cortex that is primarily driven by the actomyosin network. We previously reported that Protocadherin 7 (PCDH7) enriches at the cell surface during mitosis which is required for building up the full mitotic rounding pressure. Here we showed that PCDH7 gets palmitoylated and interacts with the palmitoyltransferase, ZDHHC5. Both PCDH7 and ZDHHC5 co-localize at the mitotic cell surface, and they translocate to the cleavage furrow during cytokinesis. PCDH7s localization depends on palmitoylation activity of ZDHHC5. Loss of expression of PCDH7 impairs active RhoA and phospho-myosin levels at the cleavage furrow and increases the rate of multinucleated cells. This work uncovers a palmitoylation-dependent translocation mechanism for PCDH7 and attributes a regulatory role to contributing actomyosin activity during cytokinesis.

cell biology↗

bioRxiv2020

Roles of developmentally regulated KIF2A alternative isoforms in cortical neuron migration and differentiation

KIF2A is a microtubule-depolymerizing kinesin motor protein with essential roles in neural progenitor division and axonal pruning during brain development. KIF2A is alternatively spliced in nervous tissue by specific RNA-binding proteins. However, how different KIF2A isoforms function during development of the cerebral cortex is not known. Here, we focus on three Kif2a isoforms expressed in mouse embryonic and postnatal cerebral cortex. We show that KIF2A is essential for dendritic pruning of primary cortical neurons in mice and that the functions of all three isoforms are sufficient for this process. Interestingly, only two of the isoforms can sustain radial migration of cortical neurons while a third isoform, lacking a key stretch of twenty amino acids, is ineffective. By proximity-labeling-based interactome mapping for individual KIF2A isoforms, we provide novel insight into how isoform specific interactions can confer changes to KIF2A protein function. Our interactome mapping identifies previously known KIF2A interactors, proteins localized to the mitotic spindle poles, and unexpectedly, also translation factors, ribonucleoproteins and proteins that are targeted to the mitochondria and ER, suggesting a novel transport function for KIF2A.

developmental biology↗

bioRxiv2018

Host-pathogen coevolution increases genetic variation in susceptibility to infection

It is common to find considerable genetic variation in susceptibility to infection in natural populations. We have investigated whether natural selection increases this variation by testing whether host populations show more genetic variation in susceptibility to pathogens that they naturally encounter than novel pathogens. In a large cross-infection experiment involving four species of Drosophila and four host-specific viruses, we always found greater genetic variation in susceptibility to viruses that had coevolved with their host. We went on to examine the genetic architecture of resistance in one host species, finding that there are more major-effect genetic variants in coevolved host-parasite interactions. We conclude that selection by pathogens increases genetic variation in host susceptibility, and much of this effect is caused by the occurrence of major-effect resistance polymorphisms within populations.

evolutionary biology↗