Molecular cloning of the gene for p85 that regulates the initiation of cytokinesis in Tetrahymena.
Tetrahymena p85 is localized to the presumptive division plane before division furrow formation; its molecular weight in SDS-polyacrylamide gel electrophoresis differs in wild-type and temperature-sensitive cell-division-arrest mutant cdaA1 cells. At the restrictive temperature, p85 localization and division furrow formation are not observed in cdaA1 cells. In this study, we purified p85 and cloned a wild-type p85 cDNA. The deduced amino acid sequence of p85 was composed mainly of two kinds of repeat sequences. One of these contained regions homologous to a calmodulin-binding site and a part of actin, and the other contained a region homologous to a part of a cdc2 kinase homologue. Moreover, we cloned a cDNA encoding the cdaA1 p85. There was no difference in the predicted amino acid sequences of wild-type and cdaA1 p85, suggesting that the difference in molecular weight between p85 in wild-type and mutant cells is caused by a disorder of posttranslational-modification mechanisms of p85 in the cdaA1 cell.
Gonda
K
K
Institute of Biological Sciences, University of Tsukuba, Tsukuba, Ibaraki, 305-8572, Japan.
Nishibori
K
K
Ohba
H
H
Watanabe
A
A
Numata
O
O
D000199:Actins / Q000737:chemistry; D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D015152:Blotting, Northern; D015139:Blotting, Southern; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2; D017871:Calcium-Calmodulin-Dependent Protein Kinases / Q000737:chemistry; D018797:Cell Cycle Proteins / Q000235:genetics* / Q000276:immunology / Q000302:isolation & purification; D002455:Cell Division / Q000235:genetics / Q000502:physiology; D003001:Cloning, Molecular; D016054:DNA, Protozoan / Q000032:analysis; D008969:Molecular Sequence Data; D015800:Protozoan Proteins / Q000235:genetics* / Q000276:immunology / Q000302:isolation & purification; D012689:Sequence Homology, Nucleic Acid; D013768:Tetrahymena / Q000166:cytology / Q000235:genetics*
D000199:Actins; D018797:Cell Cycle Proteins; D016054:DNA, Protozoan; D015800:Protozoan Proteins; C404904:p85 protein, Tetrahymena; D054732:Calcium-Calmodulin-Dependent Protein Kinase Type 2; D017871:Calcium-Calmodulin-Dependent Protein Kinases