稻瘟病菌3-磷酸甘油醛脱氢酶基因的克隆及序列分析

Isolation and Sequencing of the Glyceradehide- 3 -Phosphate Dehydrogenase Gene of Magnapothe grisea

以PCR为基础结合cDNA文库构建，分两段克隆稻瘟病菌的3-磷酸甘油醛脱氢酶基因（gpd），分别测序、合并，获得该基因编码区全部1011bp的核苷酸序列，可以编码336个氨基酸和1个终止密码子TAA。该序列与其它12种丝状真菌的已知gpd基因序列有着高度的同源性。它们的核苷酸序列同源性为61．4％～86．6％，氨基酸序列同源性为64．6％～863％。尤其在酶的活性功能区，不同丝状真菌间有着近100％的同源性。稻瘟病菌gpd基因密码子的使用具有明显的偏向性。

The glyceradehyde - 3 - phosphate dehydrogenase gene of Magnaporthe grisea wascloned by using a simple efficient method. 51 and 3l fragments of cDNA were clonedand sequenced respectively and the full sequence of cDNA containing ; Ollbp nucleoticacids was obtained after combining these two sequences. The cDNA encodes 336 aminoacids and a terminal codon, TAA. The homologies of nucleotic acid and amino acid sequences between M. grlsea and other 12 filamentous fungi are 61. 4% -86. 6% and 64- 6%- 86. 4 % separately. Approximately 100 % homology is found in functional region of theenzyme among different filamentous fungi. The usage of the codon is biased.