中文摘要：

黄酮类化合物在植物中参与过滤紫外线、固氮和花色形成等过程，异黄酮对人体有抗氧化、预防乳腺癌等保健作用。查尔酮还原酶（chalconereductase，CHR）是植物中参与黄酮类化合物代谢的重要酶。克隆大豆查尔酮还原酶基因并构建植物表达载体，有助于进一步研究其功能和异黄酮的代谢过程。采用RT-PCR方法，从栽培大豆（Gly-cinemax）南农1138-2中，克隆得到了第14号染色体上的一个编码大豆查尔酮还原酶（chalconereductase，CHR）的基因，命名为GmCHR。该基因含有948bp长的编码区序列（CodingDNASequence，CDS），编码315个氨基酸。预测其蛋白质分子量为35．5kDa，等电点为6．32。与其他豆科植物中的查尔酮还原酶相比，GmCHR蛋白序列与葛藤（Puerari．aemontana）CHR的相似性最高，达94％。组织表达分析表明，在自然生长条件下GmCHR在叶中的表达量最大；其次是种子；在花和茎中相同；在根中的表达量最小。利用Gateway方法获得植物过表达载体pMDC83．GmCHR，经检测表明过表达载体已成功转化农杆菌EHAl05，为今后进一步了解GmCHR在大豆异黄酮代谢过程中的功能提供材料基础。

英文摘要：

Flavonoids are involved in UV filtration, symbiotic nitrogen fixation and floral pigmentation in plants. Isoflavones have potential effects on human health, such as antioxidant activity, preventing breast cancer and other cancers. Chalcone re- ductase （CHR） is an important enzyme involved in flavonoid biosynthesis. Cloning of soybean chalcone reductase and construc- tion of its plant expression vector would help study its function and the phenylpropanoid pathway. A gene encoding CHR on chromosome 14 was cloned from the cultivated soybean（ Glycine max）cultivar Nannong 1138-2 using RT-PCR,and was desig- nated as GmCHR. This gene contains a coding DNA sequence （CDS） of 948 bp, and the corresponding protein consists of 315 a- mino acids. The protein is estimated to have a molecular weight of 35.5 kDa and isoelectric point of 6.32. Comparing with the amino acid sequence of CHR from other legume species, GmCHR has a highest similarity of 94% with the CHR from Puerariae montana. The mRNA abundance of GmCHR was the highest in leaves,followed by seeds,flowers,stems and roots under normal growth conditions. A plant over-expression vector of pMDC83-GmCHR was constructed by Gateway technology, and was trans- ferred into Agrobacterium EHA105 ,which would provide the opportunity to study the function of GmCHR in soybean flavonoid biosynthesis.