Wilson P W, Harding M, Lawson D E
Nucleic Acids Res. 1985 Dec 20;13(24):8867-81. doi: 10.1093/nar/13.24.8867.
Two DNA fragments coding for chick CaBP have been isolated and sequenced. cDNA was prepared from enriched intestinal mRNA and cloned in pUC12. The recombinant clones were screened by differential hybridisation with 32P-cDNA probes synthesized from vitamin D replete and deficient chick intestinal mRNA. Two clones had outstanding affinity with the +D probe. Hybrid-arrested and hybrid-selected translation systems showed that both clones hybridised to mRNA coding for immunoprecipitable CaBP. The mRNA for CaBP has a 100 bp G,C rich sequence before a 786 bp coding region followed by 1250 nucleotides 3' untranslated region. Nucleotides coding for the Ca-binding sites show a high degree of homology for Ca-binding sites in chick calmodulin and rat intestinal CaBP. The amino acid sequence specified by the longest open reading frame contains five Ca-binding sites but is too large for the native CaBP; post-translational modification must therefore occur.
已经分离并测序了两个编码鸡钙结合蛋白（CaBP）的DNA片段。从富集的肠mRNA制备cDNA，并克隆到pUC12中。用从维生素D充足和缺乏的鸡肠mRNA合成的32P-cDNA探针通过差异杂交筛选重组克隆。两个克隆与+D探针具有显著的亲和力。杂交阻止和杂交选择翻译系统表明，两个克隆都与编码可免疫沉淀的CaBP的mRNA杂交。CaBP的mRNA在786bp编码区之前有一个100bp富含G、C的序列，后面跟着1250个核苷酸的3'非翻译区。编码钙结合位点的核苷酸与鸡钙调蛋白和大鼠肠CaBP中的钙结合位点具有高度同源性。由最长开放阅读框指定的氨基酸序列包含五个钙结合位点，但对于天然CaBP来说太大；因此必须发生翻译后修饰。
