Chlamydomonas axonemal dynein assembly locus ODA8 encodes a conserved flagellar protein needed for cytoplasmic maturation of outer dynein arm complexes. Issue 1 (7th February 2015)

• Record Type: Journal Article
• Authors: Desai, Paurav B.; Freshour, Judy R.; Mitchell, David R.
• Is Part Of: Cytoskeleton. Volume 72:Issue 1(2015:Jan.)
• Page Start: 16
• Page End: 28
• Publication Date: 2015-02-07
• Subjects: Cytoskeleton -- Periodicals; 571.65405
• DOI: 10.1002/cm.21206
• Languages: English
• ISSNs: 1949-3584

Abstract

<abstract abstract-type="main"> <title> <x xml:space="preserve">Abstract</x> </title> <p>The <italic>Chlamydomonas reinhardtii oda8</italic> mutation blocks assembly of flagellar outer dynein arms (ODAs), and interacts genetically with <italic>ODA5</italic> and <italic>ODA10</italic>, which encode axonemal proteins thought to aid dynein binding onto axonemal docking sites. We positionally cloned <italic>ODA8</italic> and identified the gene product as the algal homolog of vertebrate LRRC56. Its flagellar localization depends on ODA5 and ODA10, consistent with genetic interaction studies, but phylogenomics suggests that LRRC56 homologs play a role in intraflagellar transport (IFT)‐dependent assembly of outer row dynein arms, not axonemal docking. ODA8 distribution between cytoplasm and flagella is similar to that of IFT proteins and about half of flagellar ODA8 is in the soluble matrix fraction. Dynein extracted <italic>in vitro</italic> from wild type axonemes will rebind efficiently to <italic>oda8</italic> mutant axonemes, without re‐binding of ODA8, further supporting a role in dynein assembly or transport, not axonemal binding. Assays comparing preassembled ODA complexes from the cytoplasm of wild type and mutant strains show that dynein in <italic>oda8</italic> mutant cytoplasm has not properly preassembled and cannot bind normally onto <italic>oda</italic> axonemes. We conclude that ODA8 plays an important role in formation and transport of mature dynein complexes during flagellar assembly. © 2014 The Authors. Cytoskeleton Published by Wiley Periodicals, Inc.</p> </abstract>