The physiological acquisition of amoeboid motility in nematode sperm: Is the tail the only thing the sperm lost?

Abstract

SUMMARYNematode spermatozoa are highly specialized amoeboid cells that must acquire motility through the extension of a single pseudopod. Despite morphological and molecular differences with flagellated spermatozoa (including a non-actin-based cytoskeleton), nematode sperm must also respond to cues present in the female reproductive tract that render them motile, thereby allowing them to locate and fertilize the egg. The factors that trigger pseudopod extension in vivo are unknown, although current models suggest the activation through proteases acting on the sperm surface resulting in a myriad of biochemical, physiological, and morphological changes. Compelling evidence shows that pseudopod extension is under the regulation of physiological events also observed in other eukaryotic cells (including flagellated sperm) that involve membrane rearrangements in response to extracellular cues that initiate various signal transduction pathways. An integrative approach to the study of nonflagellated spermatozoa will shed light on the identification of unique and conserved processes during fertilization among different taxa.Mol.

Assaying Environmental Nickel Toxicity Using Model Nematodes

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Chlorpyrifos exposure reduces reproductive capacity owing to a damaging effect on gametogenesis in the nematode Caenorhabditis elegans

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New Insights into the Mechanism of Fertilization in Nematodes

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