甘蔗细胞质型苹果酸脱氢酶基因的克隆及其表达分析

Cloning and Expression Analysis of Cytosolic Malate Dehydrogenase Gene from Sugarcane

摘要:

对甘蔗(Saccharum officinarum L.)叶片全长cDNA 文库进行测序,获得了1 个细胞质型苹果酸脱氢酶(cMDH)基因的全长cDNA 序列,命名为Sc-cMDH。生物信息学分析表明,该基因全长1314 bp,开放阅读框为999 bp,编码332 个氨基酸。SccMDH与其他植物cMDH 的氨基酸序列同源性高达86.5%~97.0%。Sc-cMDH 包含典型的NAD⁺ 结合基元T¹¹GAAGQI¹⁷ 和催化基元I¹⁸⁴WGNH¹⁸⁸,还有相当保守的6 个半胱氨酸残基,因此推断该基因为细胞质型NAD-MDH。定量PCR 分析结果表明,该基因在甘蔗叶片和根中的表达量高于茎。

Abstract:

A full-length cDNA sequence of sugarcane (Saccharum officinarum L.) cytosolic malate dehydrogenase (cMDH) gene, named as Sc-cMDH, was obtained from sugarcane full-length cDNA library by EST sequencing and bioinformatics analysis. The full-length of Sc-cMDH was 1314 bp with 999 bp open reading frame, encoding 332 amino acids. Sc-cMDH shared 86.5%~97.0% of amino acids with cMDH from other 9 species. Sc-cMDH contains typical NAD⁺ binding motif (T¹¹GAAGQI¹⁷) and catalytic motif (I¹⁸⁴WGNH¹⁸⁸). Real-time PCR analysis showed that the expression of Sc-cMDH was higher in leaves and roots than that in stems of sugarcane.