【摘要】 [目的]获得雨生红球藻中紫外抗性蛋白(Uv resistance locus 8,UVR8)的cDNA序列全长,并进行生物信息分析。[方法]以雨生红球藻为研究对象,通过同源克隆方法获得紫外抗性蛋白UVR8的cDNA序列全长,并通过生物信息手段对其理化性质、蛋白结构及系统进化进行分析。[结果]序列分析表明,HaeUVR8的编码区全长为1554 bp,共编码517个氨基酸,预测理论等电点为5.56,理论分子量为54.31 kD。通过BLASTp分析,与拟南芥中UVR8的相似性达到51%,与莱茵衣藻中UVR8的相似性达到59%。通过蛋白保守结构域分析,HaeUVR8蛋白中存在UVR8蛋白的典型结构域,包括7个叶片螺旋结构和保守的色氨酸残基。系统进化分析表明,高等植物和真核绿藻来源UVR8s有共同祖先。[结论]本研究首次获得雨生红球藻中编码UVR8的基因序列,发现其结构与高等植物UVR8相似,暗示二者可能有相似的作用机制,为雨生红球藻中UVR8的表达、功能研究奠定基础,同时为解析雨生红球藻适应紫外光的分子机制提供线索。更多还原

【Abstract】 [Objective]The full-length complementary DNA(cDNA)sequence of a novel ultraviolet-B photoreceptor Uv resistance locus 8(UVR8)from the green alga Haematococcus pluvialis was obtained,which was analyzed by bioinformatics.[Method]The homology cloning and rapid-amplification of cDNA ends(RACE)strategies were applied to obtain the sequence of Haeuvr8.The physical and chemical properties,structure and evolution were analyzed by bioinformatics method.[Result]The cloned cDNA of Haeuvr8 contained an open reading frame(ORF)of 1554 bp and encoded a protein of 517 amino acids.The deduced protein had a calculated molecular mass of 54.31 kD with an estimated isoelectric point(pI)of 5.56.Multiple sequence alignment analysis revealed that HaeUVR8 was homologs to known UVR8 s,e.g.,Arabidopsis thaliana(51 %)and Chlamydomonas reinhardatii(59 %).Conserved domains analysis indicated that the typical domain of the UVR8 were highly conserved in the protein sequences of HaeUVR8,including 7 conserved bladed propellers and conserved tryptophan residues.The phylogenetic analysis of the UVR8 s implied that HaeUVR8 showed higher similarity to the UVR8 s from high plants and green algae,which indicated that they shared a common ancestor origin.[Conclusion]In this study,the gene sequence encoding UVR8 in Haematococcus pluvialis was obtained for the first time,and its domain was similar to that of higher plant UVR8,suggesting that they might have similar mechanisms of action.The above results laid the foundation for further study on gene expression and functional identification, which would provide clues for the analysis of the molecular mechanism of Haematococcus pluvialis to adapt to ultraviolet light.更多还原