title: The "acrosomal synapse": Subcellular organization by lipid rafts and scaffolding proteins exhibits high similarities in neurons and mammalian spermatozoa.
abstract: Mammalian spermatozoa are highly polarized cells composed of two morphological and functional units, each optimized for a special task. Although the apparent division into head and tail may as such represent the anatomical basis to avoid random diffusion of their special sets of signaling proteins and lipids, recent findings demonstrate the presence of lipid raft-derived membrane platforms and specific scaffolding proteins, thus indicating that smaller sub-domains exist in the two functional units of male germ cells. The aim of this review is to summarize new insights into the principles of subcellular organization in mammalian spermatozoa. Special emphasis is placed on recent observations indicating that an "acrosomal synapse" is formed by lipid raft-derived membrane micro-environments and multidomain scaffolding proteins. Both mechanisms appear to be responsible for ensuring the attachment of the huge acrosomal vesicle to the overlaying plasma membrane, as well as for preventing an accidental spontaneous loss of the single acrosome.
authors.affiliation: Walther-Straub-Institute of Pharmacology and Toxicology; Ludwig-Maximilians-University; Munich, Germany.
authors.forename: Nele
authors.initials: N
authors.lastname: Zitranski
authors.forename: Heike
authors.initials: H
authors.lastname: Borth
authors.forename: Frauke
authors.initials: F
authors.lastname: Ackermann
authors.forename: Dorke
authors.initials: D
authors.lastname: Meyer
authors.forename: Laura
authors.initials: L
authors.lastname: Vieweg
authors.forename: Andreas
authors.initials: A
authors.lastname: Breit
authors.forename: Thomas
authors.initials: T
authors.lastname: Gudermann
authors.forename: Ingrid
authors.initials: I
authors.lastname: Boekhoff