A Chlamydomonas homologue of the putative murine t complex distorter Tctex-2 is an outer arm dynein light chain.
Molecular analysis of a 19,000-Mr protein from the Chlamydomonas flagellum reveals that it is homologous to the t complex-encoded protein Tctex-2, which is a candidate for one of the distorter products that cause the extreme transmission ratio distortion (meiotic drive) of the murine t complex. The 19,000-Mr protein is extracted from the axoneme with 0.6 M NaCl and comigrates with the outer dynein arm in sucrose density gradients. This protein also is specifically missing in axonemes prepared from a mutant that does not assemble the outer arm. These data raise the possibility that Tctex-2 is a sperm flagellar dynein component. Combined with the recent identification of Tctex-1 (another distorter candidate) as a light chain of cytoplasmic dynein, these results lead to a biochemical model for how differential defects in spermiogenesis that result in the phenomenon of meiotic drive might be generated in wild-type vs t-bearing sperm.
Patel-King
R S
RS
Department of Biochemistry, University of Connecticut Health Center, Farmington, Connecticut 06032-3305, USA.
Benashski
S E
SE
Harrison
A
A
King
S M
SM
D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics*; D001483:Base Sequence; D015152:Blotting, Northern; D015139:Blotting, Southern; D018833:Chaperonins / Q000737:chemistry / Q000235:genetics; D016825:Chlamydomonas reinhardtii / Q000737:chemistry* / Q000235:genetics; D003001:Cloning, Molecular; D017931:DNA Primers; D018744:DNA, Plant / Q000032:analysis; D004398:Dyneins / Q000737:chemistry / Q000235:genetics*; D047908:Intracellular Signaling Peptides and Proteins; D008297:Male; D051379:Mice; D008869:Microtubule-Associated Proteins; D008969:Molecular Sequence Data; D009687:Nuclear Proteins / Q000737:chemistry / Q000235:genetics*; D012333:RNA, Messenger / Q000032:analysis; D017386:Sequence Homology, Amino Acid; D013081:Sperm Motility / Q000502:physiology; D013082:Sperm Tail / Q000737:chemistry; D044767:Ubiquitin-Protein Ligases; D056427:t-Complex Genome Region
D001426:Bacterial Proteins; D017931:DNA Primers; D018744:DNA, Plant; C533386:Dynlt1b protein, mouse; D047908:Intracellular Signaling Peptides and Proteins; D008869:Microtubule-Associated Proteins; D009687:Nuclear Proteins; D012333:RNA, Messenger; C096191:light chain protein p28, Chlamydomonas; C116196:PPP1R11 protein, human; D044767:Ubiquitin-Protein Ligases; D018833:Chaperonins; D004398:Dyneins