Cloning and Expression Analysis of Gibberellin Receptor Gene CsGID1a in Tea Plant (Camellia sinensis)

GID1 (Gibberellin insensitive dwarf1), as the soluble gibberellin (GA) receptor in GA signaling pathway, plays the vital role in GA reactions.In this study, the homologous gene of GID1 was isolated with RT-PCR and RACE-PCR from tea plant (Camellia sinensis).The obtained cDNA sequence, named CsGID1a, had the full-length of 1411 bp containing a 1023 bp open reading frame (ORF), encoding 341 amino acid residues, and was submitted to GenBank with accession number JX235369.The bioinformatics characterization indicated that CsGID1a was a non-secretory protein without a signal peptide.The molecular weight and theoretic isoelectric point of CsGID1a are 38.53 kD and 5.62, respectively.CsGID1a was located in the nucleus, encoding a protein with one transmembrane domain.CsGID1a contained hormone sensitive lipsase family (HSL) conserved domains, HGG and GXSXG motif, and shared the plant carboxylesterase tertiary structure.Homologous alignment and phylogenetic tree showed that CsGID1a shared over 60% amino acid sequence similarity with that of other species, and had the highest similarity (87%) and the closest genetic relationship to Vitis vinifera.The real-time PCR analysis showed that the expression of CsGID1a was down-regulated by high concentration of GA 3 (1.0×10 - mol L -1 ) and reduced slowly during the treatment for five hours.The further experiments suggested that the expression of CsGID1a was also decreased in the process of bud sprouting.These results demonstrated that CsGID1a and GA could be associated with bud bursting in tea plant in spring.