Novel Insights into the Regulation of Ethylene Biosynthesis/Action: Protein Turnover by a Ripening Related FBOX Protein in Tomato

摘要

FBOX proteins target either EIN3 (EBF1 and EBF2) or EIN2 (ETP1 and ETP2) for protein degradation in Arabidopsis thaliana. Here we report the functional characterization of a novel ripening related FBOX protein from tomato we have designated S1FBOX1. SIFBOX1 transcript levels peak during the later stages of ripening. An RNAi SIFBOX1 construct, driven by the constitutive 35S CaMV promoter was deployed into tomato and the resulting transgenic plants were characterized. SIFBOX1 gene expression was lowerin transgenic RNAi lines than in WT control plants. Primary transgenic plants have delayed petal senescence, similar to the ethylene insensitive mutant NEVERRIPE (Nr). We hypothesize it regulates a novel mechanism for ethylene signaling or biosynthesis in tomato.