Gene/Protein Disease Symptom Drug Enzyme Compound
Pivot Concepts:   Target Concepts:
Query: EC:2.7.11.22 (cdc2)
 8,319 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Deepwater rice (Oryza sativa) is adapted to survive conditions of severe flooding over extended periods of time. During such periods adventitious roots develop to provide water, nutrients, and anchorage. In the present study the growth of adventitious roots was induced by treatment with ethylene but not auxin, cytokinin, or gibberellin. Root elongation was enhanced between 8 and 10 h after submergence. The population of cells in the S phase and expression of the S-phase-specific histone H3 gene increased within 4 to 6 h. Within 6 to 8 h the G2-phase population increased. Cell-cycle activation was accompanied by sequential induction of a cdc2-activating kinase homolog, R2, of two cdc2 genes, cdc2Os-1 and cdc2Os-2, and of three cyclin genes, cycA1;3, cycB2;1, and cycB2;2, but only induction of the R2 gene expression preceded the induction of the S phase, possibly contributing to cell-cycle regulation in the G1 phase. Both cdc2 genes were expressed at slightly higher levels during DNA replication. Transcripts of the A-type cyclin accumulated during the S and G2 phases, and transcripts of the B-type cyclins accumulated during the G2 phase. Cyclin expression was induced at all nodes with a similar time course, suggesting that ethylene acts systemically and that root primordia respond to ethylene at an early developmental stage.
 ...
PMID:Adventitious root growth and cell-cycle induction in deepwater rice 988 Mar 42

Cyclins are known to activate cyclin-dependent protein kinases, which are essential for cell cycle progression in eukaryotes. We isolated full-length cDNAs encoding rice mitotic cyclins named CycA1; os; 1 and CycB2;os;1, which are related to A- and B-type cyclins, respectively, from animals. To characterize the function of these mitotic cyclins, as well as that of another B-type cyclin, CycB2;os;2, each cDNA was introduced into yeast cells. When cDNAs encoding CycA1;os;1, CycB2;os; or CycB2;os;2 were overexpressed in the yeast mutant DLI, which is deficient in G1 cyclins, the mutant phenotype was rescued, indicating that these mitotic cyclins are functional in yeast cells. When the cDNA encoding CycB2;os;1 was expressed in the wild-type yeast strain, the cells lost the ability to grow, whereas the expression of either cycA1;os: 1 or cycB2;os;2 did not inhibit growth. In situ hybridization of these mitotic cyclin genes with rice root apices and counterstaining of chromosomes with a DNA-specific dye revealed that cycA1;os;1 is expressed from the G2 phase to the early M phase, while transcripts of cycB2:os;1 and cycB2;os;2 accumulated until the end of mitosis. Our results indicate that these B2-type cyclins may be involved in the control of mitosis, in combination with a G2/M-phase CDK.
 ...
PMID:Molecular characterization of mitotic cyclins in rice plants. 1051 18