Isolation, Cloning And Expression Of Genes Coding Zinc Finger Protein In Latex Of Hevea Brasiliensis

Natural rubber, which is a product of secondary metabolite, is a very important industrial material. Its unique properties make it can not be replaced by any alternative synthetic materials. Hevea brasiliensis is the most important plant producing natural rubber because of its higher yield and excellent quality. However, the fact is that there are some factors to limit the rubber production, which makes the yield of rubber far behind the demand in industry. It is urgent to explore new approaches to improve the rubber yield of Hevea brasiliensis.There are some genes that express prominently in the latex, including some transcript factors. These genes closely relate with latex regeneration in latieiferous system and stress resistance in rubber trees. The purpose of this research is to clone these latex-specific transcript factors, and explore their expression trend under the stimulation of different hormones. It helps to further illustrate the regulate pattern between transcript factors and latex regeneration genes. It will provide some guides for molecular breeding of high yield strains.In this study, mRNAs are isolated from rubber latex and leaves respectively. Through the hybridization of these cDNAs and the microarray of Arobidopsis,105 genes show up-regulated in rubber latex, including elongation factor Tu, sterol 24-C-methyltransferase, thioredoxin H-type 1, and zinc finger (C3HC4-type RING finger) family protein etc., and 151 genes show down-regulated in rubber leaves. After the analysis of bio-informatic software, four genes encoding C3HC4-type RING finger protein, including one latex-specific zinc finger protein, are chosen for next research. These four genes are cloned from cDNA and genomic DNA, and analyzed the distribution of intron. The real time quantitative PCR is applied to research the expression trend of these genes under five different hormones.There are two findings, one is that these four genes are all positively regulated by ABA, ethylene, JA, SA, but negatively regulated by 2,4-D, another is that all genes show a periodic change, but decrease on the expression with the time prolong of stimulation, which needs further research. Four genes are all most sensitive to JA, and their expression level increase significantly and immediately after stimulated by JA.The expression trend of rubber transferase (HRT) gene is smilar to that of four zinc finger protein genes under the stimulation of five different hormones. This shows that HRT gene may be regulated by zinc finger protein genes.