Cloning and sequencing of the gene for a Tetrahymena fimbrin-like protein.
Tetrahymena F-actin-binding protein, which induces bundling of Tetrahymena F-actin, was localized to a division furrow during cytokinesis. We report here the cloning and characterization of the gene and cDNA of a Tetrahymena F-actin-binding protein. The cDNA encodes a protein comprising 579 deduced amino acids with a calculated molecular mass of 65.9 kDa. The predicted amino acid sequence shares 37.7, 41.8, and 39% identity with the sequences of yeast fimbrin, Arabidopsis thaliana fimbrin, and Dictyostelium discoideum plastin, respectively. The Tetrahymena F-actin-binding protein also shares two actin-binding domains previously identified in the fimbrin/plastin family, but lacks the EF-hand Ca2+-binding motif, suggesting that this protein is a novel-fimbrin-like protein in Tetrahymena. Moreover, we cloned a genomic DNA encoding the Tetrahymena fimbrin-like protein and performed Southern and Northern hybridizations. The results indicate that the genomic DNA possesses 9 introns and that both the gene and transcript of Tetrahymena fimbrin-like protein are single. Thus, we suggest that Tetrahymena fimbrin-like protein localizes to the division furrow and probably cross-links actin filaments in a Ca(2+)-insensitive manner during cytokinesis.
Watanabe
A
A
Institute of Biological Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8572, Japan.
Yonemura
I
I
Gonda
K
K
Numata
O
O
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D015139:Blotting, Southern; D002352:Carrier Proteins / Q000737:chemistry / Q000235:genetics*; D003001:Cloning, Molecular; D004269:DNA, Bacterial / Q000302:isolation & purification; D018076:DNA, Complementary / Q000302:isolation & purification; D017125:Genes, Protozoan; D008562:Membrane Glycoproteins / Q000737:chemistry / Q000235:genetics*; D008840:Microfilament Proteins / Q000737:chemistry / Q000235:genetics*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D010750:Phosphoproteins / Q000737:chemistry; D010802:Phylogeny; D017422:Sequence Analysis, DNA; D017386:Sequence Homology, Amino Acid; D016808:Tetrahymena thermophila / Q000737:chemistry / Q000235:genetics*; D014158:Transcription, Genetic
D002352:Carrier Proteins; D004269:DNA, Bacterial; D018076:DNA, Complementary; C034037:F-actin-binding proteins; D008562:Membrane Glycoproteins; D008840:Microfilament Proteins; D010750:Phosphoproteins; C026742:plastin