中文摘要：

MONOCULM 1（MOC1）基因在植物腋分生组织和腋芽的形成中发挥重要作用,是植物分蘖关键调控基因。本研究利用同源基因克隆法结合RT-PCR、RACE技术从甘蔗品种ROC22中克隆获得MOC1的同源基因,命名为Sc MOC1。生物信息学分析发现该基因的c DNA序列包含一个长度为1299 bp的开放阅读框,编码432个氨基酸残基组成的含有GRAS保守结构域的非分泌蛋白,其分子量为45.43 k D,理化等电点p I为6.98。序列比对分析显示Sc MOC1与高粱（Sorghum bicolor（L.）Moench）、赖草（Leymus secalinus（Georgi）Tzvel.）、水稻（Oryza sativa L.）等禾本科植物同源蛋白氨基酸序列一致性较高;系统进化树分析显示其与高粱、小米草（Setaria italica（L.）P.Beauv.）、玉米（Zea mays L.）等禾本科植物MOC1同源蛋白亲缘关系最近;Sc MOC1在甘蔗品种ROC22中的序列变异分析发现,30个克隆得到的序列中共有46个SNP位点和29处In Del位点,其中1个位点发生的单个碱基缺失和另一个位点的4个碱基插入是造成基因编码蛋白序列变化的主要原因。中性检测表明,Sc MOC1在ROC22中遵循中性进化模型。采用实时荧光定量PCR分析Sc MOC1在甘蔗品种ROC22分蘖期不同组织部位（根、茎、叶、分蘖芽、叶鞘、生长点）、茎尖生长点和不同发育阶段腋芽（幼嫩腋芽、半大腋芽、较大腋芽、成熟休眠腋芽）的表达特征,结果显示Sc MOC1在分蘖期的ROC22中的表达具有组织特异性,在生命活跃的茎尖生长点处表达量最高;在腋芽形成发育过程中该基因表达总体呈现出＂升-降-升-降＂的趋势,说明Sc MOC1基因可能在甘蔗腋芽形成发育阶段中发挥作用。以上研究可推测Sc MOC1在甘蔗的分蘖性状调控上扮演重要的角色。本研究为Sc MOC1的功能研究及其在甘蔗产量分子辅助育种中的利用奠定基础。

英文摘要：

MONOCULM 1（ MOC1）,a gene that is important in the regulation of plant tillering,which plays a significant role in the formation of plant axillary meristem and axillary bud. In this study,the homolog of MOC1 which named Sc MOC1 was cloned from sugarcane variety ROC22 by a series of technologies including homologous gene cloning method,reverse transcription PCR（ RT-PCR） and rapid amplification of cDNA ends（ RACE）. Bioinformatics analysis showed that the cDNA of Sc MOC1 contained a complete open reading frame with a length of 1299 bp and encoded a secreted protein containing a GRAS conservative structure domain. The protein was predicted to encode 432 amino acid residues with a molecular mass of 45. 43 k D and bioelectric point value of 6. 98. Sequence alignment analysis showed Sc MOC1 keep a high sequence identity with some poaceae family plants homologous proteins such as Sorghum bicolor（ L.） Moench,Leymus secalinus（ Georgi） Tzvel. and Oryza sativa L.. The geneticrelationship of Sc MOC1 and its homologous proteins was analyzed and showed that Sc MOC1 had a closest evolutionary relationship with it＇s homologous proteins from Sorghum bicolor（ L.） Moench,Setaria italica（ L.） P. Beauv. and Zea mays L. in the NJ phylogenetic tree. In order to understand the sequence variation of Sc MOC1 in ROC22,we cloned Sc MOC1 from sugarcane variety ROC22 and genetic transformed to Escherichia coli,then 30 clones were randomly selected to sequence and analysis,totally 46 SNPs and 29 In Dels were identified in these clones. Among these variation sites,one deletion and the other 4 insertion of bases were the main causes of the changes for the gene encoding protein sequences. Neutrality tests showed that no purifying selection occurred of Sc MOC1 in ROC22. Real time fluorescent quantitative-PCR（ q PCR） was used to analyze the expression pattern of the gene in six different tissues（ root,stem,leaf,tiller bud,leaf sheath and stem apex） of tillering stage sugarcane and stem apex,axillary buds with dif