English (United Kingdom)

https://curated-unify.zendy.io/wp-json/zendy-region/v1/featured_content/oa?rat=en

https://curated-unify.zendy.io/wp-json/zendy-region/v1/highlighted_journal/

Global: Zendy Plus annual

Presents the access of premium content as premium feature

Premium Content

Presents the keyphrase highlighting as premium feature

Keyphrase Highlighting

Presents the summarisation as premium feature

Summarisation

Insights

Presents the pdf analysis as premium feature

PDF Analysis

Presents the zaia usage as premium feature

ZAIA

Global: Zendy Plus monthly

Global: Zendy Tools annual

Global: Zendy Tools monthly

Global: Zendy Free Plan

Biochemical fractionation of axonemal microtubules yields the protofilament ribbon (pf-ribbon), an insoluble structure of 3–4 longitudinal protofilaments composed primarily of alpha/beta tubulin, tektins A, B and C, and two previously uncharacterized polypeptides of 77 kDa and 83 kDa. We have isolated the 77/83 kDa polypeptides (termed Sp77 and Sp83) from sperm flagella of the sea urchin Stronglyocentrotus purpuratus and raised polyclonal antibodies against them. Sp77 and Sp83 copurify exclusively with the pf-ribbon. Both the anti-Sp77 and anti-Sp83 antibodies detected the nine outer doublets and the basal bodies of sea urchin sperm by immunofluorescence microscopy. In addition, the anti-Sp83 antibody, but not the anti-Sp77 antibody, detected a single 83 kDa polypeptide on immunoblots of unfertilized sea urchin egg cytoplasm, and a single polypeptide of 80 kDa on blots of isolated mitotic spindles from Chinese hamster ovary (CHO) cells. Previous studies have shown that tektins are present in the basal bodies and centrosomes/centrioles of cells ranging from clam to human. We found that anti-Sp83 decorates the spindle poles in sea urchin zygotes, and the interphase centrosome and spindle poles in CHO cells. In CHO cells arrested in S phase with aphidicolin, anti-Sp83 detects multiple centrosomes. The staining of the centrosome was not disrupted by prolonged nocodazole treatment, suggesting that the 80 kDa polypeptide is associated with the centrioles themselves. Our observations demonstrate that, like tektins, Sp77 and Sp83 are structural proteins associated with stable doublet microtubules, and may be components of basal bodies and centrioles of sea urchins and mammalian cells.

Two proteins isolated from sea urchin sperm flagella: structural components common to the stable microtubules of axonemes and centrioles