Functional analysis of Arabidopsis cyclin A3

Abstract

Cyclin D and Cyclin E are known to regulate the G1/S phase progression during the cell cycle. However, the homolog of cyclin E has not been identified in plants. We investigated expression of Arabidopsis cyclin genes during the cell cycle by using the cell suspension culture MM2d, and revealed that the transcripts of two cyclin A3 genes (CycA3;1, CycA3;2) accumulated in the G1/S phase. In situ hybridization showed that CycA3;1 and CycA3;4 specifically expressed at the shoot apical meristem and leaf primordia. We investigated the hormonal response of CycA3 genes in seedling and cell suspension culture, and transgenic plants over-expressing CycA3s were also analyzed in terms of cell division and differentiation.