家蚕MLP基因的克隆及其结构分析

HEREDITAS (Beijing) 2007年9月，29(9): 1097―1102 ISSN 0253-9772

研究报告

收稿日期: 2007−02−09; 修回日期: 2007−03−13

基金项目: 国家自然科学基金项目(编号：30371087)和国家高技术研究发展计划(863计划)项目资助(编号：2006AA10A119) [Supported by the National Natural Science Foundation of China (No. 30371087) and the National Hi-Tech Research and Development Program (863) of China (No. 2006AA10A119)]

作者简介: 刘岩(1976−), 女, 河南温县人, 助研, 博士, 研究方向：昆虫分子生物学。E-mail: mayanly@ 通讯作者: 孟智启(1953−), 男, 浙江杭州人, 研究员, 研究方向：昆虫分子生物学。E-mail: mengzq2001@

DOI: 10.1360/yc-007-1097

家蚕MLP 基因的克隆及其结构分析

刘岩, 牛宝龙, 翁宏飚, 沈卫锋, 何丽华, 齐晓朋, 孟智启

浙江省农业科学院蚕桑研究所, 杭州 310021

摘要: 利用生物信息学的方法快速获得家蚕MLP (Muscle LIM protein, MLP)基因cDNA 电子序列, 经RT-PCR 生物验证正确, 登录GenBank (No. DQ311195)。MLP 基因cDNA 长2 327 bp, ORF 全长1 485 bp, 编码产生494个氨基酸。该MLP 基因组DNA 含有11个外显子, 10个内含子, 所有内含子/外显子边界都符合典型的GT/AG 剪切模式。MLP 基因编码的蛋白富含Gly (14.4%), 分子量约为53.03 kDa, 等电点(PI )为8.29。通过BLAST 分析发现该基因编码的家蚕肌肉LIM 蛋白, 含有5个保守的LIM 结构域, 家蚕的另一种LIM 蛋白(AAR23823)含一个LIM 结构域, 两者可能是通过可变剪切产生; 后者可能通过竞争作用调节前者在肌细胞中的功能。MLP 的克隆为进一步研究其体内功能奠定了基础。 关键词: 家蚕; MLP ; 表达序列标签(EST); LIM 结构域

Cloning and structural analysis of MLP in the silkworm, Bombyx mori

LIU Yan, NIU Bao-Long, WENG Hong-Biao, SHEN Wei-Feng, HE Li-Hua, QI Xiao-Peng, MENG Zhi-Qi

Sericulture Research Institute , Zhejiang Academy of Agricultural Sciences , Hangzhou 310021, China

Abstract : The LIM domain is found in a wide variety of eukaryotic proteins that regulate gene expression and cell differ-entiation during development. Muscle LIM protein (MLP ) gene in Bombyx mori has been cloned by blasting its EST data-base and PCR test in present report. The resulting sequence covers 2 327 bp of cDNA (GenBank accession No. DQ311195). It has a complete open reading fragment and encodes a 494 amino acid protein. Genomic DNA sequence contains 11 exons and 10 introns, with intron splicing following the GT-AG rule. M.W. and PI of the predicted MLP in Bombyx mori are 53.03 kDa and 8.29 respectively. A single LIM domain linked to a glyscine-rich region is found in a previously deposited LIM protein (AAR23823) in Bombyx mori . MLP identified in this report encodes a protein with five tandem LIM-glycine modules. The two LIM proteins could be produced by alternative splicing and both are probably involved in muscle cell differentiation. This work provides foundation for further research on the in vivo function of MLP.

Keywords: Bombyx mori ; MLP ; expression sequence tag (EST); LIM domain

LIM 是3种转录因子线虫Lin-11、鼠Isl-1和线虫Mec-3名称首字母的缩写[1,2]。LIM 家族蛋白都含有一个或多个保守的LIM 结构域。LIM 结构域是由一段

富含半胱氨酸的(CX2CX16-23HX2CX2CX2C- X16-23CX2-3(C/H/D))序列组成[3,4], 其中保守的半胱氨酸、组氨酸及天冬氨酸残基形成具有Zn 2＋结合