Chromosomal distribution and coding capacity of the human endogenous retrovirus HERV-W family.
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.
Voisset
C
C
Unité Mixte 103 CNRS-bioMérieux, Ecole Normale Supérieure de Lyon, France.
Bouton
O
O
Bedin
F
F
Duret
L
L
Mandrand
B
B
Mallet
F
F
Paranhos-Baccala
G
G
D000595:Amino Acid Sequence; D000818:Animals; D015139:Blotting, Southern; D002874:Chromosome Mapping; D002893:Chromosomes, Human, Pair 3 / Q000235:genetics; D002896:Chromosomes, Human, Pair 6 / Q000235:genetics; D002897:Chromosomes, Human, Pair 7 / Q000235:genetics; D020077:Endogenous Retroviruses / Q000235:genetics* / Q000378:metabolism*; D010450:Endopeptidases / Q000235:genetics; D015686:Gene Products, env / Q000737:chemistry / Q000235:genetics; D005814:Genes, Viral; D015752:Genes, env / Q000235:genetics; D015750:Genes, gag / Q000235:genetics; D006801:Humans; D008969:Molecular Sequence Data; D010920:Placenta / Q000378:metabolism; D016133:Polymerase Chain Reaction
D015686:Gene Products, env; D010450:Endopeptidases