日本凋毛藻(Griffithsiajaponica)硫氧还蛋白基因及其编码的蛋白特征

Characteristics of Thioredoxin Gene and Its Encoded Protein Sequences From Griffithsia japonica

从日本凋毛藻的表达序列标记 EST库中筛选到 2 条全长的编码硫氧还蛋白的 cDNA序列,分别命名为GjTRX1和GjTRX2。将这2条基因编码的蛋白序列与其它藻类(包括酵母)进行比较,结果表明不同物种及同一物种间TRX的相似性都较差,除GjTRX2编码的蛋白序列外,所有蛋白在活性位点序列 WCGPC处都完全保守。推测GjTRX1属于细胞质内分布的硫氧还蛋白。GjTRX1序列推导的蛋白二级结构单元与以往报道的传统上保守的TRX的二级结构单元类型一致,但是顺序有所不同。

Two full-length encoded thioredoxin(TRX) cDNA sequences were isolated from Griffithsia japonica expressed sequence tag(EST) liabrary and were named GjTRX1 and GjTRX2, respectively. The two encoded protein sequences from Griffithsia japonica were compared with those from other algae(including yeast), and it is shown from the comparison results that the similarities between the TRXs from different species are poor, and all proteins except the GjTRX2 encoded protein sequence are conserved at the active site molif WCGPC. GjTRX1 is supposed to be TRX distributed in the cytoplasm. The secondary protein structure elements deduced by the GjTRX1 sequence were similar to those of reported conservative TRX, but the difference in order of arrangement was observed.