Wehrli M, DiAntonio A, Fearnley I M, Smith R J, Wilcox M
MRC-Laboratory of Molecular Biology, Cambridge, UK.
Mech Dev. 1993 Sep;43(1):21-36. doi: 10.1016/0925-4773(93)90020-x.
The Drosophila position-specific integrins (PS integrins or PS antigens) comprise two heterodimeric complexes, alpha PS1 beta PS and alpha PS2 beta PS. With the cloning of alpha PS1 described here, we complete the characterization of the primary structure of the three PS integrin subunits. We have purified the alpha PS1 subunit, obtained peptide sequence and isolated genomic and cDNA clones. The encoded alpha PS1 protein contains the cysteine pattern of the cleaved alpha integrins, three putative metal binding domains and shows the other characteristic features of alpha integrins. Regions of sequence variation indicate that alpha PS1 is distinct from all other alpha chains. The transcript analysis shows that the patterns of both alpha PS1 mRNA and protein expression are the same, suggesting that the gene is controlled transcriptionally. We compare the gene structures of the Drosophila alpha PS1, alpha PS2, the human alpha IIb and alpha X (p150,95) and the C. elegans F54G8.3 integrins. We find several positions and phases of introns conserved which, supported by conservation also in the amino acid sequence, indicates that they all derive from a common ancestral gene.
果蝇位置特异性整合素（PS整合素或PS抗原）由两种异二聚体复合物组成，即αPS1βPS和αPS2βPS。随着此处所述αPS1的克隆，我们完成了对三种PS整合素亚基一级结构的表征。我们纯化了αPS1亚基，获得了肽序列，并分离了基因组和cDNA克隆。编码的αPS1蛋白包含裂解的α整合素的半胱氨酸模式、三个假定的金属结合结构域，并显示出α整合素的其他特征。序列变异区域表明αPS1与所有其他α链不同。转录本分析表明，αPS1 mRNA和蛋白质表达模式相同，表明该基因受转录调控。我们比较了果蝇αPS1、αPS2、人类αIIb和αX（p150,95）以及秀丽隐杆线虫F54G8.3整合素的基因结构。我们发现内含子的几个位置和相位是保守的，氨基酸序列中的保守性也支持这一点，这表明它们都源自一个共同的祖先基因。
