Analysis of the expression of Oncidium tryptophan synthase alpha subunit（OTSA）in response to high temperature
Date Issued
2006
Date
2006
Author(s)
Shen, Yu-Hsing
DOI
zh-TW
Abstract
Development of the Inflorescence of Oncidium could be shortened under high temperature in summer, but the qualities in terms of the length and branch number, drop dramatically. We have no idea about the mechanism of branching, and growing of inflorescence and what kinds of genes involved in regulation. For understanding how Oncidium's Inflorescence develop under high temperature, we cloned genes which affect inflorescence of Oncidium under high temperature. We used three-year-old Gower Ramsey plants as material, and cultured them under moderate temperature（28/23℃）and high temperature（35/30℃）. We used DDRT-PCR（differential display reverse transcription PCR）to clone 298 genes from the top 2 cm of inflorescences. We chose one gene which could affects the growth and development of inflorescence. Expression of this gene is higher under optimal temperature than high temperature. We named it as Oncidium Tryptophan Synthase Alpha subunit(OTSA). Tryptophan is the precursor of the plant hormone-indole acetic acid (IAA). IAA can promote the expression of PsGA 3 oxidase and repress the expression of PsGA 2 oxidase in pea, and promote the growth of stem. We used 5’RACE to obtain cDNA of OTSA and construct a vector with a promoter of Heat Shock Protein 101. Because transformation of Oncidium is difficult, we transform this fusion gene to Arabidopsis thaliana by Agrobacteria. We also investigated the expression of endogenous tryptophan synthase alpha subunit gene(AtTRP3) in Arabidopsis thaliana and found AtTRP3 expressed less amount in inflorescence under high temperature than under optimal temperature.
Subjects
色氨酸合成酶
Ocidium
tryptophan synthase
Type
other