Functional Studies of FIN219 Involved in Drought and Salt Stress in Arabidopsis thaliana

• Main Authors: Meng-Hua Sung, 宋孟樺
• Other Authors: Hsu-Liang Hsieh
• Format: Others
• Language: zh-TW
• Published: 2016
• Online Access: http://ndltd.ncl.edu.tw/handle/53831537247768740151

碩士 === 國立臺灣大學 === 植物科學研究所 === 104 === Being immobile, plants use hormones to control their growth when they encounter abiotic stresses. Jasmonates, mainly associated with biotic stresses, also participate in abiotic stress responses. FIN219 (FAR-RED INSENSITIVE 219) is a protein recognized in light signaling pathway, and also discovered to have the ability to conjugate jasmonic acid (JA) with isoleucine (Ile), leading to the formation of JA-Ile. Our lab found that FIN219 and one of blue light receptors-CRY1 (cryptochrome1) antagonized with each other under blue light condition. Previous study revealed that the cry1/2 mutant showed a drought resistance. FIN219 was able to inhibit the CRY1 levels, which suggests the involvement of FIN219 in salt and drought stresses. Moreover, our previous studies indicated that FIN219 played a role in ethylene response and affected several ERF (ethylene responsive factor) transcription factors. Current data showed that FIN219 changed its location under salt stress and the survival rate of fin219-2 seedlings was also reduced under salt stress. However, the growth of fin219-2 was less inhibited compared to Col-0 under osmotic stress. Moreover, FIN219 protein levels decreased under salt and drought stresses. These data indicate that FIN219 may participate in drought and salt responses. Quantitative real-time PCR analyses revealed that some ERFs expressed differently under salt stress between Col-0 and fin219-2. Besides, the levels of HY5 (ELONGATED HYPOCOTYL 5) changed under both stresses. Pull-down assays showed the interaction between HY5 and several ERFs. Further studies revealed that the root lengths of erf9 and erf13 were influenced under salt stress, indicating the involvement of ERF9 and ERF13 in salt stress response. Taken together, the involvement of FIN219 in drought and salt responses may be through negatively and positively regulating cry1 and HY5-ERFs signaling networks. We will further examine the phenotype of ERF mutants under drought and salt stresses in order to confirm the involvement of FIN219 in these stress responses.