甘蔗ADP/ATP转运蛋白酶基因克隆及其序列的生物信息学分析

摘要：【研究目的】甘蔗(Saccharum officinarum Linn) 是C4光合途径作物，有着特殊的能量代谢系统，研究其能量代谢过程的ADP/ATP转运蛋白酶基因具有重要的意义。【方法】本研究采用同源克隆原理和PCR技术克隆甘蔗AAC转运蛋白酶基因，并应用生物信息学方法，对其进行多序列比对分析、物理性质分析、三级结构预测、亚细胞定位、跨膜区域预测和疏水性分析。【结果】克隆获得甘蔗AAC cDNA序列全长为1170bp，包括一个可编码387氨基酸的完整ORF。生物信息学分析显示，AAC家族基因的N端序列相对不保守，C端序列高度保守；其的分子量是42.265 kD，理论等电点是9.79，预测其为稳定的蛋白；GRAVY值为-0.099；含有6个跨膜区域；其6个跨膜螺旋(TM1-TM6)跨越磷脂双分子层结构，盐桥可能是通过中间的3个连接螺旋α1-α3共同构成的；定位在细胞质的概率为60.9%。【结论】本研究获得甘蔗AAC 完整ORF序列，并通过生物信息学预测该基因所编码的蛋白为一个稳定跨膜蛋白，其可能定位在细胞质。这些研究为甘蔗AAC基因的深入研究和应用奠定初步基础。

Molecular Cloning and bioinformatics-based functional analysis of a cDNA Encoding the ATP/ADP Translocator in Sugarcane

【OBJECTIVE】To investigate the genes regulating biomass and energy in C4 Sugarcane(Saccharum officinarum L). 【METHOD】The ADP/ATP carrier(AAC) gene which is closely related to the energy metabolism was cloned through homology-based cloning , and the sequences was analyzed through the bioinformatics method which analyzes sequence alignment, physical properties, protein tertiary structure, protein subcellular localization, prediction of transmembrane segments and hydrophobicity. 【RESULTS】A 1170bp AAC cDNA sequence was obtained, the sequence contained a 1164 bp ORF coding for a protein of 387 aa. A bioinformatics-based functional analysis shows that the AAC genes of different species are unconserved in N-terminal, but are highly conserved in C terminal. The molecular weigh of ACC is 42.265 kD. The theoretical isoelectric point is 9.79. The possibility of subcellular localization in cytoplasm is 60.9%.The GRAVY is -0.099, is presumed to be a stable protein with six transmembrane segment, and hydrophobicity estimation shows three of the six transmembrane segment may be as the salt bridge to connected the phospholipid bilayer. 【CONCLUSION】In summary, a AAC cDNA with full ORF was cloned, it can be speculated to be a stable protein with transmembrance segments,and location in cytoplasm. These studies aims to provide the theoritical basis of molecular mechanism for AAC regulation in sugarcane.