Identification, Expression and IAA-Amide Synthetase Activity Analysis of Gretchen Hagen 3 in Papaya Fruit (Carica papayaL.) during Postharvest Process.
Auxin plays essential roles in plant development. Gretchen Hagen 3 (GH3) genes belong to a major auxin response gene family and GH3 proteins conjugate a range of acylsubstrates to alter the levels of hormones. Currently, the role ofGH3genes in postharvest physiological regulation of ripening and softening processes in papaya fruit is unclear. In this study, we identified sevenCpGH3genes in a papaya genome database. The CpGH3.1a, CpGH3.1b, CpGH3.5, CpGH3.6, and CpGH3.9 proteins were identified as indole-3-acetic acid (IAA)-specific amido synthetases. We analyzed the changes in IAA-amido synthetase activity using aspartate as a substrate for conjugation and found a large increase (over 5-fold) during the postharvest stages. Ascorbic acid (AsA) application can extend the shelf life of papaya fruit. Our data showed that AsA treatment regulates postharvest fruit maturation processes by promoting endogenous IAA levels. Our findings demonstrate the important role ofGH3genes in the regulation of auxin-associated postharvest physiology in papaya.
Life Science and Technology School, Lingnan Normal University Zhanjiang, China.
Kaidong
K
Liu
The State Key Laboratory for Conservation and Utilization of Subtropical Agro-Bioresources, South China Agriculture UniversityGuangzhou, China; College of Agriculture and Root Biology Center, South China Agricultural UniversityGuangzhou, China.
Jinxiang
J
Wang
Life Science and Technology School, Lingnan Normal University Zhanjiang, China.
Haili
H
Li
Life Science and Technology School, Lingnan Normal University Zhanjiang, China.
Jundi
J
Zhong
Life Science and Technology School, Lingnan Normal University Zhanjiang, China.
Shaoxian
S
Feng
Life Science and Technology School, Lingnan Normal University Zhanjiang, China.
Yaoliang
Y
Pan
Life Science and Technology School, Lingnan Normal University Zhanjiang, China.
Changchun
C
Yuan
GH3 gene family; auxin; papaya; postharvest; ripening; softening