Soybean Ribulose Bisphosphate Carboxylase Small Subunit Gene Family: Gene Structure and Regulation of Gene Expression: Progress Report for the Period 6/1/86-5/31/87

摘要

The effects of white light and far-red light on transcription rates and steady state mRNA levels of two closely related soybean RuBPCss genes, SRS1 and SRS4, have revealed a system of light regulated RNA turnover. Transcription of these genes is 30 to 50 fold higher in fully light grown seedlings than in etiolated seedlings. In contrast, steady state mRNA levels are only 8 to 10 fold higher in light than in darkness. Furthermore, when etiolated seedlings are placed in light, RuBPCss transcription increases to the level found in light grown seedlings within 12 hours, but the steady state mRNA levels of these genes do not begin to increase for at least 24 hours. We therefore hypothesize that light induction of RuBPCss transcription in soybean is paralleled by a significant increase in the mRNA turnover rate, perhaps related to the concomitant increase in the rate of translation. Interestingly, the high turnover rate appears to be maintained for some time after light grown plants are treated with far-red light, even though this treatment rapidly shuts down RuBPCss transcription. 4 refs. (ERA citation 12:032629)