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Title: Cleavage-furrow formation without F-actin in Chlamydomonas
Significance Studies of eukaryotic cell division have focused on the actomyosin ring, whose filaments of F-actin and myosin-II are hypothesized to generate the contractile force for ingression of the cleavage furrow. However, myosin-II has a very limited taxonomic distribution, whereas division by furrowing is much more widespread. We used the green algaChlamydomonas reinhardtiito investigate how a furrow can form without myosin-II and the potential roles of F-actin in this process. Although F-actin was associated with ingressing furrows, its complete removal only modestly delayed furrowing, suggesting that an actin-independent mechanism (possibly involving microtubules) drives furrow ingression. Such a mechanism presumably emerged early in eukaryotic evolution and may still underlie cell division in a diverse range of modern species.  more » « less
Award ID(s):
1515220 1818383
PAR ID:
10173683
Author(s) / Creator(s):
 ;  ;  ;  
Publisher / Repository:
Proceedings of the National Academy of Sciences
Date Published:
Journal Name:
Proceedings of the National Academy of Sciences
Volume:
117
Issue:
31
ISSN:
0027-8424
Format(s):
Medium: X Size: p. 18511-18520
Size(s):
p. 18511-18520
Sponsoring Org:
National Science Foundation
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