摘  要：BRD（Bromodomain）蛋白是参与染色质转录调控的特异性蛋白质，具组蛋白乙酰转移酶的活性。BRD蛋白在人类中已有较多研究，而在高等植物中其成员和功能还不明确。本研究采用生物信息学方法分别鉴定出水稻和拟南芥中14个和15个BRD基因。亚细胞定位分析表明，多个水稻和拟南芥BRD蛋白定位在细胞核内。系统发育分析表明，植物BRD蛋白可分为3个亚族，说明其成员已经发生了分化；在系统发育树末端分别发现了1对和4对水稻和拟南芥旁系同源基因，说明物种特异性扩张是该家族进化的主要动力。基于EST和芯片数据的表达分析表明，多数水稻BRD基因在花、愈伤组织和穗子中表达。66506

毕业论文关键词：水稻，拟南芥，BRD基因，系统发育分析，表达分析

Abstract：BRD (Bromodomain) proteins are specific proteins that participate in chromatin transcription regulation. They often possess histone acetyl-transferase activity. BRD proteins have been extensively studied in human beings; however, BRD members and their functions in higher plants remain illusive. In this analysis, we identified 14 and 15 BRD genes, respectively, from rice and Arabidopsis using bioinformatics approaches. Subcellular localization prediction revealed that many rice and Arabidopsis BRD proteins were localized in nucleus. Phylogenetic analysis showed that plant BRD proteins were pided into 3 subfamilies, suggesting that pergence has occurred among this family. One and four pairs of rice and Arabidopsis paralogs, respectively, were identified at the terminal of the phylogenetic tree, indicating that species-specific expansion contributes to the evolution of this family. Gene expression analysis using EST and microarray data revealed that most rice BRD genes were expressed in spikelets, callus and panicles. 

Keywords：rice, Arabidopsis thaliana, BRD gene, phylogenetic analysis, expression analysis

目  录

1  引言 4

2  材料与方法 4

2.1  序列检索和复制事件分析 4

2.2  蛋白质等电点和亚细胞定位预测 4

2.3  多序列对比和系统发育分析 5

2.4  表达分析 5

3  结果与分析 5

3.1  水稻和拟南芥中的BRD基因 5

3.2  植物BRD基因染色体分布和复制事件 5

3.3  植物BRD蛋白系统发育分析 7

3.4  OsBRD基因表达模式分析 7

结  论 12

参 考 文 献 13

致  谢 14

1  引言

BRD结构域因在果蝇蛋白质Brahma中发现而得名，该结构域广泛存在于多种染色质相关蛋白和几乎所有组蛋白乙酰转移酶中，通过乙酰化组蛋白尾部的特殊的氨基酸残基来启动转录。BRD结构域具有非典型左手螺旋四螺旋环结构，由110个氨基酸组成[1]。BRD蛋白具有组蛋白乙酰转移酶活性，并与染色体基因转录有关。研究表明，BRD蛋白在平衡染色体结构上起到了重要作用[2]。近年来，很多学者对一些BRD蛋白进行了深入系统研究，发现其表达水平失调或功能紊乱与多种肿瘤的发生有关。BRD蛋白的shRNA及超末端结构抑制剂显示出强大的抗肿瘤活性，有望成为治疗肿瘤的新靶点，为治疗肿瘤提供了新的思路[3]。BRD-2可促进E2F调控细胞周期的进展，该机制的异常可能是白细胞增多的遗传因素[4]。论文网