Villa A, Strina D, Frattini A, Faranda S, Macchi P, Finelli P, Bozzi F, Susani L, Archidiacono N, Rocchi M, Vezzoni P
Istituto di Tecnologie Biomediche Avanzate, Consiglio Nazionale delle Ricerche, Milan, Italy.
Genomics. 1996 Jul 15;35(2):312-20. doi: 10.1006/geno.1996.0362.
We have previously reported (Villa et al. (1993), Genomics 18: 223) the characterization of the human ZNF75 gene located on Xq26, which has only limited homology (less than 65%) to other ZF genes in the databases. Here, we describe three human zinc finger genes with 86 to 95% homology to ZNF75 at the nucleotide level, which represent all the members of the human ZNF75 subfamily. One of these, ZNF75B, is a pseudogene mapped to chromosome 12q13. The other two, ZNF75A and ZNF75C, maintain an ORF in the sequenced region, and at least the latter is expressed in the U937 cell line. They were mapped to chromosomes 16 and 11, respectively. All these genes are conserved in chimpanzees, gorillas, and orangutans. The ZNF75B homologue is a pseudogene in all three great apes, and in chimpanzee it is located on chromosome 10 (phylogenetic XII), at p13 (corresponding to the human 12q13). The chimpanzee homologue of ZNF75 is also located on the Xq26 chromosome, in the same region, as detected by in situ hybridization. As expected, nucleotide changes were clearly more abundant between human and orangutan than between human and chimpanzee or gorilla homologues. Members of the same class were more similar to each other than to the other homologues within the same species. This suggests that the duplication and/or retrotranscription events occurred in a common ancestor long before great ape speciation. This, together with the existence of at least two genes in cows and horses, suggests a relatively high conservation of this gene family.
我们之前曾报道过（Villa等人，(1993)，《基因组学》18: 223）位于Xq26的人类ZNF75基因的特征，该基因与数据库中其他锌指基因仅有有限的同源性（低于65%）。在此，我们描述了三个在核苷酸水平上与ZNF75具有86%至95%同源性的人类锌指基因，它们代表了人类ZNF75亚家族的所有成员。其中之一，ZNF75B，是一个定位于12q13染色体的假基因。另外两个，ZNF75A和ZNF75C，在测序区域保持一个开放阅读框，并且至少后者在U937细胞系中表达。它们分别定位于16号和11号染色体。所有这些基因在黑猩猩、大猩猩和猩猩中都是保守的。ZNF75B的同源物在所有三种大猩猩中都是假基因，在黑猩猩中它位于10号染色体（系统发育XII）的p13位置（对应于人类的12q13）。通过原位杂交检测发现，ZNF75的黑猩猩同源物也位于Xq26染色体的同一区域。正如预期的那样，人类与猩猩之间的核苷酸变化明显比人类与黑猩猩或大猩猩同源物之间的变化更为丰富。同一类别的成员彼此之间比同一物种内的其他同源物更为相似。这表明复制和/或反转录事件发生在大猩猩物种形成之前很久的一个共同祖先中。这一点，再加上牛和马中至少存在两个基因，表明这个基因家族具有相对较高的保守性。
