Identification of a Light-Harvesting Chlorophyll a/b-Binding Protein Gene in Gardenia jasminoides

Abstract

Objective: The major light-harvesting complex of photosystem II, Lhcbs, are assembled in its trimeric form, equipped with chlorophyll and xanthophylls, embedded in the thylakoid membrane of green plants, and play critical roles in harvesting light energy for photosynthesis. The objective of this work is to isolate a gene of Lhcb in Gardenia jasminoides. Methods: A Gardenia jasminoides fruit cDNA library was constructed, and the GjLhcb cDNA was isolated from the cDNA library by sequencing method. Results: The GjLhcb cDNA is 946bp, contains a predicted 795bp open reading frame that encodes 265 amino acids. A phylogenetic analysis was conducted with previously characterized Lhcbs from other plant species. A three-dimensional trimers model of GjLhcb was built. Conclusion: The phylogenetic analysis suggested that the GjLhcb has a chloroplast transit peptide, the mature form has 230 amino acids; and contains an Nterminal Thr as a potential phosphorylation site, which is important in regulation of state transitions. The threedimensional structure of GjLhcb is similar with the structure of Lhcbl in Spinacia oleracea. This is the first Lhcb identified in Gardenia jasminoides.