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橡胶树ＨＭＧ－ＣＯＡ还原酶ｃＤＮＡ序列分析结果表明，该ｃＤＮＡ长段为１３８３ｂｐ，由此推导的氨基酸序列含有４６１个氨基酸残基。ＰＣＧＥＮＥ￣（ＴＭ）分析该ｃＤＮＡ克隆与拟南芥ＨＭＧ－ＣｏＡ还原酶ｃＤＮＡ序列同源性为７９．７％，氨基酸序列同源性为８０．２％，与苍鼠氨基酸序列同源性为５１％，与血吸虫氨基酸序列同源性为４８％。（１）发现ＨＭＧ－ｏｎＡ还原酶的一级结构在动物与植物之间存在较大的差异。（２）分析ＨＭＧ－ＣｏＡ还原酶的疏水性氨基酸图谱，发现橡胶树和拟南芥这两种植物权有１个跨膜势能区域（Ｄｏｍａｉｎ），而血吸虫、苍鼠、果蝇等几种动物却有７个跨膜势能区域，这说明该酶的二级结构在动植物之间也存在着较大的差异。（３）由于所分析的几种动植物ＨＭＧ－ＣｏＡ还原酶的羧基一端未见有疏水性区域，故推测具有疏水性区域Ｎ－端蛋白质与膜相结合，而酶的羧基端由于具有亲水性则起到酶的催化中心位点。（４）比较橡胶树ＨＭＧ－ＣｏＡ还原酶和拟南芥ＨＭＧ－ＣｏＡ还原酶氨基酸同源性，发现蛋白质（酶）的Ｎ－端氨基酸同源性较低，而靠近Ｃ－端同源性较高，这说明Ｃ－端部分较为保守，估计与酶的活性中心区域有关，而Ｎ－端同源性较差，估计跟酶与结合的膜不
The HMG-COA reductase cDNA sequence analysis showed that the cDNA was 1383 bp in length and the deduced amino acid sequence contained 461 amino acid residues. PCGENE ~ (TM) analysis of the cDNA clone and Arabidopsis HMG-CoA reductase cDNA sequence homology was 79.7%, amino acid sequence homology was 80.2%, homologous with the Habitat amino acid sequence 51 %, And the amino acid sequence homology with schistosoma is 48%. (1) The primary structure of HMG-onA reductase was found to differ greatly between animals and plants. (2) The hydrophobic amino acid sequence of HMG-CoA reductase was analyzed. It was found that both the rubber tree and the Arabidopsis plant had one transmembrane potential domain, while several species such as schistosome, hamster and fruit fly There are seven transmembrane potential regions, indicating that the secondary structure of the enzyme in plants and animals there is also a big difference. (3) Since there is no hydrophobic region at one carboxyl end of several animal and plant HMG-CoA reductase analyzed, it is presumed that the N-terminal protein having hydrophobic region binds to the membrane and the carboxyl terminal of the enzyme has a hydrophilic Sex then acts as a catalytic site for the enzyme. (4) Comparing the amino acid homology between HMG-CoA reductase and Arabidopsis HMG-CoA reductase, we found that the N-terminal amino acid homology of protein (enzyme) is low, , Suggesting that the C-terminal portion is more conserved and is estimated to be involved in the active central region of the enzyme, whereas the N-terminal homology is poor, which is estimated to be not associated with the enzyme and the bound membrane