Abstract
We have utilized immunoblotting and light microscopic immunofluorescent staining methods to examine the expression and localization of sea urchin kinesin-II, a heterotrimeric plus end-directed microtubule motor protein (previously referred to as KRP((85/95))), in sea urchin and sand dollar sperm. We demonstrate the presence of the 85 K and 115 K subunits of kinesin- II in sperm and localize these proteins to the sperm flagella and midpiece. The kinesin-II localization pattern is punctate and discontinuous, and in the flagella it is quite distinct from the continuous labeling present in sperm labeled with anti-flagellar dynein. The kinesin-II staining is largely insensitive to prefixation detergent extraction, suggesting that it is not associated with membranous elements in the sperm. In the midpiece the kinesin-II staining is similar to the pattern present in sperm labeled with an anti-centrosomal antibody. To our knowledge, this is the first localization of kinesin-like proteins in mature sperm and corroborates the recent identification and localization of kinesin-like proteins in the flagella and basal body of the unicellular green alga Chlamydomonas. We hypothesize that kinesin-II in the sperm may play functional roles in intraflagellar transport and/or the formation of flagella during spermatogenesis.
Original language | English (US) |
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Pages (from-to) | 29-37 |
Number of pages | 9 |
Journal | Cell Motility and the Cytoskeleton |
Volume | 38 |
Issue number | 1 |
DOIs | |
State | Published - 1997 |
Keywords
- Kinesin-II
- Sand dollar sperm
- Sea urchin
ASJC Scopus subject areas
- Cell Biology