|Liu, Hong - U OF ILLINOIS, URBANA|
Submitted to: Plant Physiology Supplement
Publication Type: Proceedings
Publication Acceptance Date: June 1, 1995
Publication Date: N/A
Technical Abstract: Photosynthesis in chilling-sensitive plants, such as tomato, is reduced by as much as 60% by a single night's chilling. While chilling is known to interfere with the normal expression of certain nuclear genes encoding chloroplast proteins, there also appear to be effects on translation. In this study, we examined the stability of rubisco activase (rca) mRNA following a chilling night. Actinomycin D was applied to intact leaves to inhibit transcription in order that the turnover time of rca mRNA in vivo could be estimated. We found that the half-life of rubisco activase mRNA was increased by the chilling treatment. In order to investigate the modulation of rca message stability by ribosome binding and/or polysome runoff assays were performed. Immunoprecipitation of the polysome runoff products by rca antisera showed that the transnational efficiency of rca mRNA is decreased after chilling even though there is approximately the same amount of mRNA associated with the polysomes. The mechanism of how chilling treatment affects rca mRNA stability in tomato and the relationship between translation efficiency and mRNA stability is under investigation. This work was supported in part by a grant from the USDA NRI-CGP, No. 91-37100-6620.