Cloning And Expression Analysis About HMGR Gene Of Taraxacum Kok-saghyz

Taraxacum kok-saghyz, also known as Russian dandelion(Taraxacum kok-saghyz Rodin, TKS), is very similar with common dandelion, both of which contain latex. However, the TKS roots contain more than 20% of the rubber, common dandelion were not. The latex extracted from the TKS roots was similar to Hevea latex in rubber particle structure and the propety. TKS could be planted in the north highland and harvested in the same year of sowing with a considable rubber production so it could be a kind of rubber-yield sodution for short-term demands and non traditional Hevea plant area.About TKS research, it was the earliest in the 1950s, mainly concentrated in the cultivation, physiology and biochemistry. Molecular biology is less. At present, rubber resources is sharp inadequacy, that makes the United States and the European Union countries attach great importance to the source of natural rubber. TKS, as a glue production plants, was again starting a shares research upsurges, particularly in the US and EU countries. Latex extraction technology and molecular biology were ones of the major research objects. In view of this and our research background of the HMGR from the Hevea brasiliensis, we chosed HMGR from TKS rubber synthetic way key enzymes, as the research object, to develop the experimental work.This research use degenerate RT-PCR and RACE technology, and cloned HMGR genes from the TKS plants. We study the sequence analysis, Bioinformatics analysis and organization quantitative expression analysis, and the main results are as follows:1. We obtained TKS’s HMGR gene. It is length for 1928 bp, including 107 bp 5’-UTR,73 bp 3’-UTR and 1749 bp ORF. In ORF, it contains starting codon ATG and termination codon TGA, whole ORF coding 582 a amino acids. There have a length of Kozak sequence In the start codon ATG near. The derived molecular weight of HMGR protein is 62.61889 kD, and isoelectric point is 5.68.2. Bioinformatics analysis shows that TKS HMGR had four catalytic structure domain:two HMG-CoA motif:EMPVGYVQIP and TTEGCLVA; two NADPH motif:DAMGMNM and GTVGGGT. The predicted peptide contained no signal suequence, not secrete proteins, contain obvious hydrophobic region; Have two across a cell membrane structure, located in A43 and A65, A85 and A107 between, belong to cross membrane protein; Predict its main positioning was in cell membranes, and has the voltage door channel, signaling and transcriptional functions. 3. Fluorescent quantitative RT-PCR was used to reveal the expression of HMGR genes in TKS tissues. We found, the expression of HMGR genes was high in the roots, seeds, leaves; pedicels is less; flowers is the least.