39. 新奇タンパク質LeEOLによるトマトACC合成酵素(LeACS2)の翻訳後制御機構の解析

概要

論文の詳細を見る
ACC synthase (ACS), which is a key enzyme in the pathway of ethylene biosynthesis, is regulated transcriptionally. However, recent studies have raised the possibility that ACS is regulated not only transcriptionally but also post-translationally. We found that LeACS2, which is tomato wound-inducible isozyme, was phosphorylated on serine-460 residue and the phosphorylation was involved in turnover of LeACS2. On the other hand, it reported that ETO1, which is the product of the gene that cause eto1 (ethylene over producer 1) mutant of Arabidopsis, interacted specifically with ACS5 and CUL3A, which is a constituent of ubiquitin E3 ligase complexes, and the C-terminus and the N-terminus of ETO1 interacted with ACS5 and CUL3A, respectively. These results suggest that ETO1 promotes ACS5 protein degradation via the ubiquitin/proteasome pathway. Since it, however, is unknown that the phosphorylation of LeACS2 is involved in interaction between ETO1-like protein and LeACS2, we tried to identify tomato ETO1 homologue and to analyze the interaction with LeACS2. As a result, we cloned the tomato ETO1 homologue, LeEOL1 (E__-TO__-1-L__-IKE), LeEOL2 and LeEOL3. LeEOL1, LeEOL2 and LeEOL3 cDNAs consist of 2930, 3194 and 3707 bp and encode 886, 911 and 949 amino acid. The primary structures of LeEOLs reveal BTB/POZ domain and TPR domain. Now, we examine the interaction between each LeEOL and LeACS2.
植物化学調節学会の論文
2004-10-13