PROBLEM TO BE SOLVED: To provide a plant regenerated from a protoplast stably transformed with a useful gene for expression. SOLUTION: A transgenic plant or plant cells are transformed with at least one control element selected from a group consisting of a sequence encoding p34cdc2, a sequence encoding a p34cdc2-like protein having cyclin-associated kinase function and a modulation element modulating the level of p34cdc2or a p34cdc2-like molecule. In the transgenic plant or plant cells, the modulation element is selected from a group consisting of p13SUC1, cyclin, cdc25, or nim-1, wee-1 and mik-1 gene products. COPYRIGHT: (C)2007,JPO&INPIT