| Photosynthesis, occured at the thylakoid in chloroplast, as the most important biochemical reaction in the world, affects directly the photosynthetic process by absorbing and transferring solar energy. The peripheral light-harvesting complex LHC of photosystemâ…¡(LHCâ…¡) plays a significant role in photosynthesis of higher plants. In addition to light-harvesting, photoprotection via heat dissipation, energy modulation and distribution, and maintenance of thylakoid are all the main functions of LHCâ…¡. Photosynthesis, as the most physiological indicator, plays a decisive role in plant growth to some extent, which representing the assimilation capacity of plant.Bamboo has great light assimilation capacity for fast growth and abundant output. It is significant to focus on the molecular mechanism of bamboo photosynthesis through bio-technology, and valuable for the development and utilization of bamboo resource. Isolation and expression of the light-harvesting chlorophyll a/b binding protein genes of bamboo were performed in this paper. The major results were described as follows:1. light-harvesting chlorophyll a/b binding protein genes (cab-PhE3, cab-PhE1, cab-PhE5, cab-PhE8, cab-PhE10 and cab-PhE11) ,which belong to lhcb1, lhcb2, lhcb3, lhcb4, lhcb5 and lhcb6 gene family respectively, were isolated from Moso (Ph. edulis) through RT-PCR and RACE technology.Results showed that, the CDS of 6 genes were all about 800~900 bp, and molecular weight of the deduced proteins were all between 28~30kD by bioinformatics analysis. According to International nucleic acid and protein databases, the deduced proteins were highly homologous to other CAB proteins, most of them more than 80%;especially to the monocotyledon plants, such as rice, maize, barely and so on, more than 90% respectively. The motifscan analysis indicated that, these proteins all had chlorophyll a/b binding domain which may bonding chlorophyll. The similar coefficient among Cab-PhE3 and Cab-PhE1, Cab-PhE5 were 72.6%, 65.7% respectively; and that of Cab-PhE8, Cab-PhE10, Cab-PhE11were 29.4%, 41.4% and 24.8% respectively; that between Cab-PhE1 and Cab-PhE5 was 66.5%. Isolation of the six light-harvesting chlorophyll a/b binding protein genes of LHCâ…¡from bamboo is very helpful to the further research on the structure and function of LHCâ…¡in different plants. 2. The light harvesting chlorophyll a/b-binding protein genes (cab-PhE3, cab-PhE1 and cab-PhE5) of Phyllostachys edulis were highly expressed in Escherichia coli.The prokaryoti expression vector, pET- cab-PhE3 -mature, pET- cab-PhE1 -mature and pET- cab-PhE5-mature,were constructed by adding restriction enzyme sites to the sequence encoding mature protein of cab-PhE3, cab-PhE1 and cab-PhE5 and then ligating to the multiple clone sites of pET-23a. The protein electrophoresis revealed that mature proteins of cab-PhE3, cab-PhE1 and cab-PhE5 were highly expressed in E. coli induced by IPTG. Molecular weight of the inducible proteins were all approximate to that of the mature protein, which would be very important for further research on in vitro reconstitution of light-harvesting Chl a/b complexes.3. The space-time expression of cab-PhE3, cab-PhE1, cab-PhE5, cab-PhE8, cab-PhE10 and cab-PhE11 genes from Ph. edulis was studied.Chlorophyll fluorescence parameters of Ph. edulis were studied in this paper. The plant was illuminated by different time of strong light treatment (2 hr, 4 hr and 6 hr). All chlorophyll fluorescence parameters were changed: Fv/Fm, qP, Yield and ETR were decreasing, while Fo and qN were increasing with the time of strong light. The expression lever variance of cab-PhE3, cab-PhE1, cab-PhE5, cab-PhE8, cab-PhE10 and cab-PhE11 genes was displayed by Real time PCR. The expression level of the six genes all decreased, especially cab-PhE3 and cab-PhE1 changed obviously. It could be deduced that cab-PhE3, cab-PhE1, cab-PhE5, cab-PhE8, cab-PhE10 and cab-PhE11 genes may be related with photoinhibition.
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