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F-actin prevents interaction between sperm DNA and the oocyte meiotic spindle in C. elegans.

ABSTRACT: Fertilization occurs during female meiosis in most animals, which raises the question of what prevents the sperm DNA from interacting with the meiotic spindle. In this study, we find that Caenorhabditis elegans sperm DNA stays in a fixed position at the opposite end of the embryo from the meiotic spindle while yolk granules are transported throughout the embryo by kinesin-1. In the absence of F-actin, the sperm DNA, centrioles, and organelles were transported as a unit with the yolk granules, resulting in sperm DNA within 2 µm of the meiotic spindle. F-actin imaging revealed a cytoplasmic meshwork that might restrict transport in a size-dependent manner. However, increasing yolk granule size did not slow their velocity, and the F-actin moved with the yolk granules. Instead, sperm contents connect to the cortical F-actin to prevent interaction with the meiotic spindle.

SUBMITTER: Panzica MT

PROVIDER: S-EPMC5551714 | biostudies-literature | 2017 Aug

REPOSITORIES: biostudies-literature

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F-actin prevents interaction between sperm DNA and the oocyte meiotic spindle in <i>C. elegans</i>.

Panzica Michelle T MT Marin Harold C HC Reymann Anne-Cecile AC McNally Francis J FJ

The Journal of cell biology 20170621 8

Fertilization occurs during female meiosis in most animals, which raises the question of what prevents the sperm DNA from interacting with the meiotic spindle. In this study, we find that <i>Caenorhabditis elegans</i> sperm DNA stays in a fixed position at the opposite end of the embryo from the meiotic spindle while yolk granules are transported throughout the embryo by kinesin-1. In the absence of F-actin, the sperm DNA, centrioles, and organelles were transported as a unit with the yolk granu ...[more]

PMID: 28637747

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