Takane K, Tanaka K, Tajima S, Okazaki K, Kouchi H
Dept. of Bioresource Science, Faculty of Agriculture, Kagawa University, Japan.
Plant Cell Physiol. 1997 Feb;38(2):149-54. doi: 10.1093/oxfordjournals.pcp.a029145.
A cDNA clone (URcot-35) was isolated from a soybean cotyledonary cDNA library using a cDNA clone (URnod-35) for nodule uricase II as a probe. URcot-35 was a 1,170-bp cDNA with an open reading frame that encoded a protein of putative 309 amino acids with a molecular mass of 35,137 Da. The nucleotide sequence of URcot-35 was identical to that of URnod-35. Expression of the URcot-35 gene in cotyledons was investigated by Northern dot-blot hybridization, by the reverse transcription-polymerase chain reaction with subsequent hybridization assays with the cDNA for nodule uricase II as a probe, and by immunoblotting analysis with a monoclonal antibody that was specific to nodule uricase II. The results suggested that the transcript of URcot-35 was present in developing cotyledons and that uricase II accumulated during the pod-filling stage. This is the first report of the isolation of cDNA for uricase II from non-symbiotic tissue and the results demonstrate that uricase II in soybean cotyledons is identical to that in soybean nodules.
以根瘤尿酸酶II的cDNA克隆（URnod - 35）为探针，从大豆子叶cDNA文库中分离出一个cDNA克隆（URcot - 35）。URcot - 35是一个1170 bp的cDNA，具有一个开放阅读框，编码一个推定的309个氨基酸的蛋白质，分子量为35137 Da。URcot - 35的核苷酸序列与URnod - 35的相同。通过Northern斑点杂交、以根瘤尿酸酶II的cDNA为探针进行后续杂交分析的逆转录 - 聚合酶链反应以及用对根瘤尿酸酶II特异的单克隆抗体进行免疫印迹分析，研究了URcot - 35基因在子叶中的表达。结果表明，URcot - 35的转录本存在于发育中的子叶中，并且尿酸酶II在荚果充实期积累。这是首次从非共生组织中分离出尿酸酶II的cDNA的报道，结果表明大豆子叶中的尿酸酶II与大豆根瘤中的尿酸酶II相同。
