Sequence analysis reveals homology between two proteins of the flagellar radial spoke.
Flagellar radial spokes contribute to the regulation of dynein arm activity and thus the pattern of flagellar bending. We have sequenced the genes for radial spoke protein 4 (RSP4) and RSP6, two of the five proteins that make up the radial spoke head in Chlamydomonas reinhardtii. The two genes, which are tightly linked genetically (B. Huang, G. Piperno, Z. Ramanis, and D.J.L. Luck, J. Cell Biol. 88:80-88, 1981), are separated by only 435 bp. They encode proline-rich polypeptides of 49.8 kDa (RSP4) and 48.8 kDa (RSP6), which are 48% identical to each other but do not resemble any previously sequenced proteins. The transcription start sites of these genes and an additional radial spoke protein gene, that for RSP3, were determined, and patterns of mRNA accumulation during flagellar regeneration were examined for the three radial spoke protein genes. These studies provide the molecular tools for a detailed analysis of radial spoke head function and assembly and for a determination of the mechanism by which the genes required to build a complex organelle are regulated.
Curry
A M
AM
Department of Biology, Yale University, New Haven, Connecticut 06511.
Williams
B D
BD
Rosenbaum
J L
JL
D000595:Amino Acid Sequence; D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics*; D001483:Base Sequence; D015152:Blotting, Northern; D015139:Blotting, Southern; D016825:Chlamydomonas reinhardtii / Q000737:chemistry / Q000235:genetics*; D004247:DNA; D005407:Flagella / Q000737:chemistry*; D005786:Gene Expression Regulation; D007700:Kinetics; D008969:Molecular Sequence Data; D010455:Peptides / Q000235:genetics; D010940:Plant Proteins; D055232:Proline-Rich Protein Domains; D011506:Proteins; D015800:Protozoan Proteins; D012333:RNA, Messenger / Q000235:genetics; D015183:Restriction Mapping; D012689:Sequence Homology, Nucleic Acid; D014158:Transcription, Genetic
D001426:Bacterial Proteins; D010455:Peptides; D010940:Plant Proteins; D011506:Proteins; D015800:Protozoan Proteins; D012333:RNA, Messenger; C060324:radial spoke protein, Chlamydomonas; D004247:DNA