Smith M J
MRC Laboratory of Molecular Biology, Cambridge, UK.
DNA Seq. 1992;3(4):247-50. doi: 10.3109/10425179209034025.
A Drosophila melanogaster gene encoding a homologue of the mammalian ER calcium binding protein, calreticulin, was cloned and the nucleotide sequence determined. Four exons can be identified, contained within 1700 bp of sequence, separated by introns of 124, 266 and 92 bases. The exons encode a 389 amino acid protein which may be a precursor form as it includes an N-terminal signal region of 17 residues that could potentially be cleaved to form a mature protein. The C-terminal region of the protein contains the established pattern of polyacidic clusters, common to calreticulins of other species and ends in the ER retention signal HDEL. Excluding the N-terminal signal region, the Drosophila protein amino acid sequence has a 67% identity to mammalian calreticulins and the length and acidity of the C-terminal zone in the insect protein are intermediate between higher mammalian and lower nematode values.
克隆了一个编码哺乳动物内质网钙结合蛋白钙网蛋白同源物的黑腹果蝇基因，并测定了其核苷酸序列。可识别出四个外显子，包含在1700 bp的序列中，由124、266和92个碱基的内含子隔开。这些外显子编码一个389个氨基酸的蛋白质，它可能是前体形式，因为它包括一个17个残基的N端信号区域，该区域可能被切割形成成熟蛋白。该蛋白的C端区域包含其他物种钙网蛋白常见的多酸性簇模式，并以内质网保留信号HDEL结尾。排除N端信号区域后，果蝇蛋白氨基酸序列与哺乳动物钙网蛋白有67%的同一性，昆虫蛋白C端区域的长度和酸度介于高等哺乳动物和低等线虫的值之间。
