Genetic Mapping of the Cloned Subgroup A Avian Sarcoma and Leukosis Virus Receptor Gene to the TVA Locus

Abstract

A chicken gene conferring susceptibility to subgroup A avian sarcoma and leukosis viruses (ASLV-A) was recently identified by a gene transfer strategy. Classical genetic approaches had previously identified a locus, TVA, that controls susceptibility to ASLV-A. Using restriction fragment length polymorphism (RFLP) mapping in inbred susceptible (TVA*S) and resistant (TVA*R) chicken lines, we demonstrate that in 93 F2 progeny an RFLP for the cloned receptor gene segregates with TVA. From these analyses we calculate that the cloned receptor gene lies within 5 centimorgans of TVA, making it highly probable that the cloned gene is the previously identified locusTVA. The polymorphism that distinguishes the two alleles ofTVA in these inbred lines affects the encoded amino acid sequence of the region of Tva that encompasses the viral binding domain. However, analysis of the genomic sequence encoding this region of Tva in randomly bred chickens suggests that the altered virus binding domain is not the basis for genetic resistance in the chicken lines analyzed.

TRIM E3 Ligases Interfere with Early and Late Stages of the Retroviral Life Cycle

“…We then analysed the ability of the TRIM proteins to interfere with viral entry defined here as all early events in the retroviral life cycle leading up to the establishment of viral gene expression ( Figure 1 A). To identify activities directed specifically against incoming retroviral capsids, all viruses carried the same subgroup A envelope glycoprotein of ALV (ALV-A) and target cells expressed the cognate receptor Tva950 [ 29 ]. To guarantee a ∼90% probability of Tva950 co-expression with each TRIM protein, plasmids encoding for both proteins were co-transfected 36 h prior to initiating infection.…”

Identification of Key Residues in Subgroup A Avian Leukosis Virus Envelope Determining Receptor Binding Affinity and Infectivity of Cells Expressing Chicken or Quail Tva Receptor

“…Several cell surface proteins have been identified as ALV receptors. Tva, the receptor for ALV(A), contains sequences related to the ligand binding region of low-density lipoprotein receptors (LDLR) (7,8,69). TvbS3, a receptor for ALV(B) and ALV(D) (13,60), TvbT, a receptor for ALV(E) (1), and TvbS1, a receptor for ALV(B), ALV(D), and ALV(E) (2), are all members of the tumor necrosis factor receptor family.…”

Production and Characterization of a Soluble, Active Form of Tva, the Subgroup A Avian Sarcoma and Leukosis Virus Receptor

“…Tva was the first ASLV receptor identified (7,72) and has been mapped to the TVA locus (6). While it has been shown to function as a viral receptor, the cellular function of Tva remains unknown.…”