Endosome mediated delivery of ceramide phosphoethanolamine (CPE) with unique acyl chain anchors to the cleavage furrow is essential for male meiosis cytokinesis

Abstract

AbstractDivision of one cell into two daughter cells is fundamental in all living organisms. Cytokinesis, the final step of cell division, begins with the formation of an actomyosin contractile ring, positioned midway between the segregated chromosomes. Constriction of the ring with concomitant membrane deposition in a spatiotemporal precision generates a cleavage furrow that physically divides the cytoplasm. Unique lipids with specific biophysical properties have been shown to localize to midbodies however, their delivery mechanisms and biological roles were largely unknown. In this study, we show that Ceramide phosphoethanolamine (CPE), the structural analog of sphingomyelin, has unique acyl chain anchors in spermatocytes and is essential for meiosis cytokinesis. We found that disengagement of the central spindle from the contractile ring but not localization of phosphatidyl inositols (PIPs) at the plasma membrane was responsible for the male meiosis cytokinesis defect in CPE deficient animals. Further, we demonstrate that enrichment of CPE in Rab7 and Rab11 positive endosomes which in turn translocate to the cleavage furrows to promote cytokinesis. Our results implicate endosomal delivery of CPE to ingressing membranes is crucial for meiotic cytokinesis.