title: Formins: Actin nucleators that regulate cytoskeletal dynamics during spermatogenesis.
abstract: Formins are a growing class of actin nucleation proteins that promote the polymerization of actin microfilaments, forming long stretches of actin microfilaments to confer actin filament bundling in mammalian cells. As such, microfilament bundles can be formed in specific cellular domains, in particular in motile mammalian cells, such as filopodia. Since ectoplasmic specialization (ES), a testis-specific adherens junction (AJ), at the Sertoli cell-cell and Sertoli-spermatid interface is constituted by arrays of actin microfilament bundles, it is likely that formins are playing a significant physiological role on the homeostasis of ES during the epithelial cycle of spermatogenesis. In this Commentary, we provide a timely discussion on formin 1 which was recently shown to be a crucial regulator of actin microfilaments at the ES in the rat testis (Li N et al.Endocrinology, 2015,in press; DOI: 10.1210/en.2015-1161, PMID:25901598). We also highlight research that is needed to unravel the functional significance of formins in spermatogenesis.
authors.affiliation: The Mary M. Wohlford Laboratory for Male Contraceptive Research; Center for Biomedical Research; Population Council ; New York, NY USA.
authors.forename: Nan
authors.initials: N
authors.lastname: Li
authors.affiliation: The Mary M. Wohlford Laboratory for Male Contraceptive Research; Center for Biomedical Research; Population Council ; New York, NY USA.
authors.forename: Dolores D
authors.initials: DD
authors.lastname: Mruk
authors.affiliation: The Mary M. Wohlford Laboratory for Male Contraceptive Research; Center for Biomedical Research; Population Council ; New York, NY USA.
authors.forename: Elizabeth I
authors.initials: EI
authors.lastname: Tang
authors.affiliation: Department of Biology; Hong Kong Baptist University ; Hong Kong, China.
authors.forename: Chris Kc
authors.initials: CK
authors.lastname: Wong
authors.affiliation: School of Biological Sciences; University of Hong Kong ; Hong Kong, China.
authors.forename: Will M
authors.initials: WM
authors.lastname: Lee
authors.affiliation: S.B.M. Srl Pharmaceuticals ; Rome, Italy.
authors.forename: Bruno
authors.initials: B
authors.lastname: Silvestrini
authors.affiliation: The Mary M. Wohlford Laboratory for Male Contraceptive Research; Center for Biomedical Research; Population Council ; New York, NY USA.
authors.forename: C Yan
authors.initials: CY
authors.lastname: Cheng
keywords: F-actin; actin nucleator; cytoskeleton; formin 1; formins; seminiferous epithelial cycle; spermatogenesis; testis