Functional characterization of an Arabidopsis bromodomain protein GTE12

• Main Authors: Yi-Jhen Wu, 吳依珍
• Other Authors: 楊俊逸
• Format: Others
• Language: zh-TW
• Published: 2011
• Online Access: http://ndltd.ncl.edu.tw/handle/26362356522118208609

碩士 === 國立中興大學 === 生物化學研究所 === 99 === In eukaryotes, DNA containing the genetic message is wrapped into a complex structure with histones called chromatin. Chromatin can regulate gene transcription through histone modification. The Arabidopsis GTE (General Transcription Factor Group E) family has twelve members including GTE1 to GTE12. They all have a bromodomain which can recognize acetyl-lysine on the histone tail and regulate gene expression. It has been reported that GTE1 can regulate signal transduction pathway to promote seed germination; GTE4 can control gene expression to affect cell numbers; GTE6 can regulate leaves development by controlling genes involved in the establishment of symmetrical leaves. Using yeast two-hybrid screening, a clone with partial GTE12 cDNA was obtained and showed strong interaction with SE (SERRATE), a key regulator in miRNA processing pathway. Further characterization found that the C-terminal domain of GTE12 was involved in the interaction with SE. Using confocal laser scanning, the fluorescent signal of GTE12-YFP was observed in the nucleus as foci and co-localized with CFP-SE. In order to know the expression pattem of GTE12 promoter, a promoter-GUS staining assay was carried out and found that GTE12 was expressed in leaves, roots and flowers, especially in stigma. Although no developmental defect was observed in gte12 mutants, a susceptible phenotype was showed in gte12 mutants when infected with Botrytis cinerea. As a result, we suggest that GTE12 maybe involved in the plant defense system as it has been showed that se mutant was susceptible to B. cinerea infection, SE may bind with GTE12 to regulate plant defense system.