SLC6 family transporter SNF-10 is required for protease-mediated activation of sperm motility in C. elegans

• Published in: Developmental biology Vol. 393; no. 1; pp. 171 - 182
• Main Authors: Fenker, Kristin E., Hansen, Angela A., Chong, Conrad A., Jud, Molly C., Duffy, Brittany A., Paul Norton, J., Hansen, Jody M., Stanfield, Gillian M.
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 01.09.2014
• Subjects: Animals; Animals, Genetically Modified; C. elegans; Caenorhabditis elegans - genetics; Caenorhabditis elegans - physiology; Caenorhabditis elegans Proteins - biosynthesis; Caenorhabditis elegans Proteins - genetics; Caenorhabditis elegans Proteins - metabolism; Cell motility; GABA Plasma Membrane Transport Proteins - biosynthesis; GABA Plasma Membrane Transport Proteins - genetics; GABA Plasma Membrane Transport Proteins - physiology; Hermaphroditic Organisms; Male; Membrane Proteins - metabolism; Morphogenesis; Mutation; Reproduction; Signaling; SLC6 transporter; Sperm; Sperm Motility - genetics; Sperm Motility - physiology; Spermatogenesis; Spermatozoa - cytology; Cell motility; Signaling; Reproduction; C. elegans; Sperm; SLC6 transporter
• ISSN: 0012-1606; 1095-564X
• DOI: 10.1016/j.ydbio.2014.06.001

Motility of sperm is crucial for their directed migration to the egg. The acquisition and modulation of motility are regulated to ensure that sperm move when and where needed, thereby promoting reproductive success. One specific example of this phenomenon occurs during differentiation of the ameboid sperm of Caenorhabditis elegans as they activate from a round spermatid to a mature, crawling spermatozoon. Sperm activation is regulated by redundant pathways to occur at a specific time and place for each sex. Here, we report the identification of the solute carrier 6 (SLC6) transporter protein SNF-10 as a key regulator of C. elegans sperm activation in response to male protease activation signals. We find that SNF-10 is present in sperm and is required for activation by the male but not by the hermaphrodite. Loss of both snf-10 and a hermaphrodite activation factor render sperm completely insensitive to activation. Using in vitro assays, we find that snf-10 mutant sperm show a specific deficit in response to protease treatment but not to other activators. Prior to activation, SNF-10 is present in the plasma membrane, where it represents a strong candidate to receive signals that lead to subcellular morphogenesis. After activation, it shows polarized localization to the cell body region that is dependent on membrane fusions mediated by the dysferlin FER-1. Our discovery of snf-10 offers insight into the mechanisms differentially employed by the two sexes to accomplish the common goal of producing functional sperm, as well as how the physiology of nematode sperm may be regulated to control motility as it is in mammals. •Identification of an SLC6 transporter that functions in sperm to promote motility.•SNF-10 is required for sperm to respond to the male protease activator.•snf-10 mutants are fertile and have competitive sperm.•SNF-10 localization is regulated during sperm activation.