A Galegae. Orientalis L. gibberellin receptor, GoGID, is involved in GA signal and over-expression enhanced GA-signaling in tobacco
Jun Li, Xuemin Wang*, Hongwen Gao, Jishan Jiang

Department of Forage Germplasm Resources, Institute of Animal Science, Chinese Academy of Agricultural Sciences, Beijing, 100193, China.
Corresponding Author: Tel: (+8610) 62816008; E-mail: wangxm@iascaas.net.cn

Abstract
Gibberellin(GA) is a well-known phytohormone that involves a wide range of plant growth, development, and environmental responses, including seed germination, stem elongation, leaf expansion, and flower and seed development. Gibberellin receptor perceive GA and transmit to cause GA-regulated reactions. In this study, an ortholog of GA receptor gene, termed GoGID, was isolated from G. orientalis. The 1732-bp full-length GoGID had a 1035-bp ORF, which encodes a peptide of 344 amino acids. The deduced amino acid sequence of GoGID protein shared high identity with other GIDs, and have conserved amino acid that essential for maintaining the GA-binding activity. The transcript of GoGID was abundant in leaves compared with roots and stems. Expression of GoGID was shown to be largely upregulated by GA₃ and IAA. Overexpression of GoGID in transgenic tobacco plants resulted in rapid growth, increased leaf area, and stem elongation. These result demonstrated that GoGID function as GA receptor enhance GA-signaling and have potential role in genetic engineering for forage improvement.

Key Words: Galegae. Orientalis L, gibberellin receptor, gene expression, Transgenic tobacco