|
|
|
|
|
|
|
||
Dynein Heavy Chain Required for Inner Arm Assembly and Flagellar Motility in Chlamydomonas
Correspondence to: Mary E. Porter, Department of Genetics, Cell Biology, and Development, University of Minnesota Medical School, Box 206, 420 Delaware St. SE, 4-102 Owre Hall, Minneapolis, MN 55455. Tel:(612) 626-1901 Fax:(612) 624-8118 E-mail:mary-p{at}biosci.cbs.umn.edu.
Flagellar motility is generated by the activity of multiple dynein motors, but the specific role of each dynein heavy chain (Dhc) is largely unknown, and the mechanism by which the different Dhcs are targeted to their unique locations is also poorly understood. We report here the complete nucleotide sequence of the Chlamydomonas Dhc1 gene and the corresponding deduced amino acid sequence of the 1 Dhc of the I1 inner dynein arm. The 1 Dhc is similar to other axonemal Dhcs, but two additional phosphate binding motifs (P-loops) have been identified in the NH2- and COOH-terminal regions. Because mutations in Dhc1 result in motility defects and loss of the I1 inner arm, a series of Dhc1 transgenes were used to rescue the mutant phenotypes. Motile cotransformants that express either full-length or truncated 1 Dhcs were recovered. The truncated 1 Dhc fragments lacked the dynein motor domain, but still assembled with the 1ß Dhc and other I1 subunits into partially functional complexes at the correct axoneme location. Analysis of the transformants has identified the site of the 1 motor domain in the I1 structure and further revealed the role of the 1 Dhc in flagellar motility and phototactic behavior.
Key Words: motors, dynein, flagella, phototaxis, inner arm
CiteULike 
Complore 
Connotea 
Del.icio.us 
Digg 
Reddit 
Technorati What's this?
This article has been cited by other articles:
|
|
