家蝇黏蛋白mucin-46基因的序列分析

Analysis of Mucin-46 cDNAs Sequence of Musca domestic

目的:分析和预测家蝇黏蛋白mucin-46基因及其编码蛋白的结构和特性。方法:利用EST测序技术从家蝇幼虫cDNA文库中获得家蝇黏蛋白mucin-46基因cDNA序列,采用美国国家生物技术信息中心(NCBI)、瑞士生物信息学研究所的蛋白分析专家系统(Expasy)中的相关工具,对该基因及其编码蛋白的基本理化性质、疏水性、信号肽、二级结构和亚细胞定位等方面进行预测和分析。结果:家蝇黏蛋白mucin-46基因的cDNA序列具有完整的开放阅读框(ORF),全长1 383 bp,编码460个氨基酸;其编码的蛋白质理论分子量为46.42 kDa,等电点4.13;无信号肽及跨膜区,属于亲水性蛋白,具有4个几丁质结合功能域,含有4个糖基化位点及多个蛋白磷酸化作用位点;二级结构β折叠(E)和无规则卷曲(L)的比例是14.13∶85.87,没有α螺旋(H)结构类型;主要分布于细胞核。结论:应用生物信息学方法从家蝇cDNA文库中筛选出了家蝇黏蛋白mucin-46基因序列并预测了其结构及功能等生物学信息,为进一步研究家蝇围食膜蛋白的功能奠定了一定的基础。

Objective： To analyze and predict the gene structure and feature of mucin-46 of Musca domestic （ MD-mucin 46） and function of its encoding protein. Methods： MD-mucin 46 was obtained by EST sequencing. Adopting relevant tools of National Center for Biotechnology Information （NCBI） and Expasy of Swiss Institute of Bioinformatics, some characters of the MD-mucin 46 gene and encoded protein sequence were predicted and analyzed in the following aspects, such as general physical and chemical properties, hydrophobicity, signal peptide, secondary structure and localization sites in cells. Results： The MD-mucin 46 complete ORF is 1 383 bp in length, encoding 460 amino acid. The pre- dicted molecular weight and isoelectric point are 46.42 kDa and 4.13. No signal peptide and trans- membrane domains were hydrophilic protein which located mainly in cell nucleus. The secondary struc- tures of βfold （E） and random coil ratio was 14.13： 85.87, withoutαhelical structure type. Conclu- sions： The cDNA sequence encoding MD-mucin 46 is screened from cDNA library of Musca domestic by bioinformatics method, and predict biological information concerning structure and function. This study provides a basis for further researching the function of MD-mucin 46.