Identification of a cellular receptor for mouse mammary tumor virus and mapping of its gene to chromosome 16

Abstract

Pseudotypes of vesicular stomatitis virus (VSV) containing envelope glycoproteins provided by C3H mammary tumor virus (MTV) instead of the normal VSV G-proteins were prepared and used to assay the presence of an MTV receptor on cells. The assay was specific as demonstrated by competition studies with excess MTV particles and neutralization of the pseudotypes with anti-MTV serum or monoclonal antibodies directed against MTV gp52. The MTV receptor was abundantly present on mouse cells but hardly detectable on nonmurine cells, including the Chinese hamster cell line E36. Somatic cell hybrids between E36 cells and GRS/A spontaneous leukemia cells (GRSL cells) and between E36 and GRS/A primary mammary tumor cells were made. The hybrids retained all Chinese hamster chromosomes but segregated mouse chromosomes. From the analysis of the isoenzymes and chromosomes of the hybrid cell lines we conclude that the gene for the receptor (MTVR-J) is located on mouse chromosome 16. of vesicular stomatitis virus with envelope antigens provided by murine mammary tumor virus. Virology 82:221-231.

Preferential expression of cellular retinoic acid binding protein in a subpopulation of neural cells in the developing mouse embryo

“…Our results indicate that high CRABP expression in the mouse occurs around the stage at which development of somites and neuromeres is initiated (day 8-9) [33]. This expression continues till day 16 of gestation and diminishes during subsequent stages of embryonic development. At day 9, the elevated CRABP expression is restricted to a subpopulation of neural cells in the developing central nervous system, a distinct group of mesenchymal cells located anterior to the forebrain, and the transverse septum of the developing liver.…”

“…The MES-1 cell line was isolated by single cell picking from an area of contracting muscle from DMSO-treated aggregates [31]. The panel of mouse-Chinese hamster hybrid cells used for chromosomal localization of the CRABP gene has been described [15, 16,171. The cells were cultured according to standard procedures.…”

Fatty acid acylation of viral proteins in murine hepatitis virus-infected cells

“…For labeling with 3H-palmitic acid, 100 txCi of 9, 10-~tt(N)-palmitic acid (15.2 Ci/mmol; New England Nuclear Corp.) in 80 per cent ethanol was dried in a glass tube and taken up in 1 ml minimal essential medium containing 5 per cent fetal calf serum; this mixture was added to the cells. After the labeling period the cells were washed twice with PBS (4°C), lysed and the viral proteins were immunoprecipitated as previously described (6) with mouse anti-MHV-A 59 (16) or rabbit anti-VSV antiserum (4). Immunopreeipitates were analysed by electrophoresis in 15 per cent polyacrylamide gels.…”

A Novel Membrane Protein Is a Mouse Mammary Tumor Virus Receptor

“…Like other retroviruses, MMTV encodes an envelope protein, consisting of two chains generated by processing a precursor polyprotein, a cell surface (SU) domain of 52 kDa and a transmembrane domain of 36 kDa (22). It is the SU protein that binds the cellular receptor for the virus, since anti-SU antibody blocks MMTV infection of cultured cells (10).…”