Underexpression of a novel gene, dia2, impairs the transition of Dictyostelium cells from growth to differentiation.
In Dictyostelium discoideum Ax-2 cells, a specific point (PS-point) in the cell cycle from which they initiate differentiation in response to starvation has been specified. Using synchronized Ax-2 cells and the differential display method, a novel gene (differentiation-associated gene 2; dia2) was isolated as one of the genes expressed specifically during the shift of Ax-2 cells from growth to differentiation. The dia2 gene codes a lysine- and leucine-rich protein with a predicted molecular mass of 16.9 kDa. Northern blot analysis has shown that the dia2 mRNA, of 0.7 kb, accumulates in differentiating cells starved just before the PS-point, while there is no detectable expression in vegetatively growing cells. Antisense-mediated gene inactivation of dia2 greatly inhibited the progress of differentiation, presumably through the reduced expression of cAMP receptor 1 (car1). Thus, the DIA2 expression was suggested to have an essential role in the initiation of differentiation, closely relating to the cAMP signaling system.
Chae
S C
SC
Biological Institute, Graduate School of Science, Tohoku University, Sendai, Aoba, 980-8578, Japan.
Inazu
Y
Y
Amagai
A
A
Maeda
Y
Y
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002453:Cell Cycle / Q000235:genetics*; D002454:Cell Differentiation; D017931:DNA Primers; D004023:Dictyostelium / Q000166:cytology / Q000235:genetics* / Q000254:growth & development; D017353:Gene Deletion; D018507:Gene Expression Regulation, Developmental; D017125:Genes, Protozoan; D008969:Molecular Sequence Data; D008970:Molecular Weight; D016133:Polymerase Chain Reaction; D011401:Promoter Regions, Genetic; D015800:Protozoan Proteins / Q000096:biosynthesis / Q000737:chemistry / Q000235:genetics*
D017931:DNA Primers; C115813:Dia2 protein, Dictyostelium; D015800:Protozoan Proteins