Chromosomal Distribution and Coding Capacity of the Human Endogenous Retrovirus HERV-W Family

Abstract

Some genomic elements of the multicopy HERV-W endogenous retroviral family have been previously identified in databases. One of them, located on chromosome 7, contains a single complete open reading frame (ORF) putatively encoding an envelope protein. We have experimentally investigated the genomic complexity and coding capacity of the HERV-W family. The human haploid genome contains at least 70, 100, and 30 HERV-W-related gag, pro, and env regions, respectively, widely and heterogeneously dispersed among chromosomes. Using in vitro transcription-translation procedures, three putative HERV-W gag, pro, and env ORFs were detected on chromosomes 3, 6, and 7, respectively, and their sequences analyzed. A 363 amino acid gag ORF containing matrix and carboxy-terminal truncated capsid domains encoded a putative 45-kDa protein. No gag-pro ORF was found, but a pro sequence containing a DTG active site was detected. Finally, the previously described 538 amino acid HERV-W env ORF, located on chromosome 7, was shown to be unique and encoded a putative 80-kDa glycosylated protein. Proteins of molecular mass identical to the one obtained by an in vitro transcription-translation procedure were detected in human placenta, using anti HERV-W Gag- and Env-specific antibodies. The absence of an HERV-W replication-competent provirus versus the existence of HERV-W-related Gag and Env proteins in healthy human placenta is discussed with respect to particle formation, physiology, and pathology.

Processed Pseudogenes of Human Endogenous Retroviruses Generated by LINEs: Their Integration, Stability, and Distribution

“…On the other hand, retroviral copies are under-represented on smaller chromosomes 16, 17, 19, 20, and 22. Generally, HERV-W elements show biased distribution toward chromosomes 3, 4, X, and particularly Y, and are less frequent on chromosomes 16, 17, 20, and 22, in agreement with experimental results (Voisset et al 2000).…”

Expression and Identification of HERV-W Family in Japanese Monkeys (Macaca fuscata)

“…The number of identified HERV-W related fragments, at least 70 copies for gag , 30 copies for env per haploid genome, is correlated with the increase in complexity from env to gag and pro regions previously described (Voisset et al ., 2000). We previously isolated fifteen env and twenty-four pol members of the HERV-W family using human monochromosomal DNAs and suggested that ret-rotransposition or chromosomal translocation had occurred during hominid evolution (Kim and Lee, 2001;Kim, 2001).…”

Les rétrovirus endogènes humains, une implication dans la schizophrénie et le trouble bipolaire

“…Parmi les différents HERV, le sous-type W (HERV-W) semble particulièrement impliqué en psychiatrie. Au moins 140 séquences appartenant à la famille HERV-W ont pu être identifiées dans l'ADN humain à ce jour dont seulement 40 présentent une séquence complète [13]. Le HERV-W a une distribution chromosomique ubiquitaire à l'exception, actuellement connue, des chromosomes 16 et 22 [12].…”