title: Non-muscle myosin IIB is essential for cytokinesis during male meiotic cell divisions.
abstract: Cytokinesis, the final stage of cell division, bisects the cytoplasm into two daughter cells. In mitotic cells, this process depends on the activity of non-muscle myosin II (NMII), a family of actin-binding motor-proteins that participate in the formation of the cleavage furrow. The relevance of NMII for meiotic cell division, however, is poorly understood. The NMII family consists of three members, NMIIA, NMIIB, and NMIIC, containing different myosin heavy chains (MYH9, MYH10, and MYH14, respectively). We find that a single non-muscle myosin II, NMIIB, is required for meiotic cytokinesis in male but not female mice. Specifically, NMIIB-deficient spermatocytes exhibit cytokinetic failure in meiosis I, resulting in bi-nucleated secondary spermatocytes. Additionally, cytokinetic failure at meiosis II gives rise to bi-nucleated or even tetra-nucleated spermatids. These multi-nucleated spermatids fail to undergo normal differentiation, leading to male infertility. In spite of the presence of multiple non-muscle myosin II isoforms, we demonstrate that a single member, NMIIB, plays an essential and non-redundant role in cytokinesis during meiotic cell divisions of the male germline.
authors: Center for Animal Transgenesis and Germ Cell Research, Department of Animal Biology, University of Pennsylvania School of Veterinary Medicine, Philadelphia, 19104, USA.
authors: Fang
authors: F
authors: Yang
authors: Qize
authors: Q
authors: Wei
authors: Robert S
authors: RS
authors: Adelstein
authors: P Jeremy
authors: PJ
authors: Wang
mesh_terms: D000818:Animals; D002455:Cell Division / Q000235:genetics / Q000502:physiology; D048749:Cytokinesis / Q000235:genetics / Q000502:physiology*; D005260:Female; D018507:Gene Expression Regulation, Developmental; D008297:Male; D008540:Meiosis / Q000235:genetics / Q000502:physiology*; D051379:Mice; D018345:Mice, Knockout; D008817:Mice, Mutant Strains; D008822:Mice, Transgenic; D046529:Microscopy, Electron, Transmission; D018995:Myosin Heavy Chains / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D024501:Nonmuscle Myosin Type IIB / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D013087:Spermatids / Q000378:metabolism / Q000648:ultrastructure; D013090:Spermatocytes / Q000378:metabolism / Q000648:ultrastructure; D013091:Spermatogenesis / Q000235:genetics / Q000502:physiology*; D013093:Spermatogonia / Q000378:metabolism / Q000648:ultrastructure; D013737:Testis / Q000166:cytology / Q000378:metabolism
chemical_list: D024501:Nonmuscle Myosin Type IIB; C103815:nonmuscle myosin type IIB heavy chain; D018995:Myosin Heavy Chains