Sures I, Crippa M
Proc Natl Acad Sci U S A. 1984 Jan;81(2):380-4. doi: 10.1073/pnas.81.2.380.
We have synthesized two oligodeoxyribonucleotide mixtures that contain sequences complementary to different parts of the hypothetical mRNA sequence of xenopsin, a biologically active octapeptide found in skin extracts from Xenopus laevis. The two primer pools were independently used to initiate reverse transcription on skin poly(A)+ RNA and the resulting cDNAs were then used to screen in parallel a cDNA library prepared from skin poly(A)+ RNA. One of the clones that hybridized with both probes was subjected to sequence analysis. It contains a nearly full-length DNA copy of a mRNA of approximately equal to 490 nucleotides that encodes a xenopsin precursor protein. The deduced precursor is 80 amino acids long, exhibits a putative signal sequence at the NH2 terminus, and contains the biologically active peptide at the COOH terminus. The region corresponding to the NH2-terminal portion of the xenopsin precursor shows a striking nucleotide and amino acid sequence homology with the precursor of PYLa, another recently described peptide from Xenopus skin.
我们合成了两种寡脱氧核糖核苷酸混合物，它们包含与异源视蛋白假定mRNA序列不同部分互补的序列。异源视蛋白是一种在非洲爪蟾皮肤提取物中发现的具有生物活性的八肽。这两个引物池被独立用于起始对皮肤聚腺苷酸加尾RNA的逆转录，然后将得到的cDNA用于平行筛选由皮肤聚腺苷酸加尾RNA制备的cDNA文库。对与两种探针都杂交的一个克隆进行了序列分析。它包含一个长度约为490个核苷酸的mRNA的几乎全长DNA拷贝，该mRNA编码一种异源视蛋白前体蛋白。推导的前体长度为80个氨基酸，在NH2末端有一个假定的信号序列，并且在COOH末端包含生物活性肽。与异源视蛋白前体的NH2末端部分相对应的区域与PYLa的前体显示出显著的核苷酸和氨基酸序列同源性，PYLa是另一种最近描述的来自非洲爪蟾皮肤的肽。
