黄芪甲苷合成差异基因克隆和鉴定(英文)

Isolation and Identification of Genes Related to Astragaloside IV Differential Expressed Synthesis in Astragalus membranaceus

黄芪甲苷(AstragalosideIV,ASI)是黄芪中的有效成分之一,具有抗炎,改善心肌,脑缺血,促淋巴细胞繁殖,促抗体生成等作用。但由于其在黄芪中含量低,以及缺乏必要的化学合成中间体,限制了其临床药用,通过基因工程方法提高其表达量将有助于其应用。本文应用了差减杂交方法(SSH)结合斑点杂交,从黄芪甲苷合成差异株系中分离鉴定了19个黄芪甲苷合成差异基因片断,其中7个具有同源序列,同源性约80%以上,而另外12个未发现同源序列,推测可能是新基因片断或者是全长cDNA的3’末端序列。

Astragaloside IV (ASI) is the effective compound of Astragalus membranaceus according to China Pharmacopoeia. Studies showed that ASI could exhibit anti-inflammatory function, improve cerebral and myocardial ischemia, and increase lymphocyte proliferation and antibody production. However, due to its low concentration in natural A. membranaceus and lack of pathway intermediate for biochemical synthesis, ASI could not be (utilized) broadly in clinic. To systematically analyze the genes related to ASI synthesis, suppression subtractive hybridization (SSH) combined with cDNA microarray was used. From the two lines of A. membranaceus hairy roots, one has high ASI content and the other low ASI content, totally 19 differentially expressed genes were (identified,) among which 7 had found homologous genes within GenBank, while other 12 didnt have and were (deducted) to be novel genes or derived from the variable 3′-terminal of full-length cDNA, which imply that they might be related to ASI synthesis.