Proteins encoded by the long terminal repeat region of mouse mammary tumor virus

Identification by hybrid-selected translation

Janis Racevskis, O. Prakash

Research output: Contribution to journalArticle

23 Citations (Scopus)

Abstract

The long terminal repeat (LTR) region of mouse mammary tumor virus (MMTV) is known to contain an open reading frame of sufficient length to code for a protein of 36,000 M(r). The coding capacity of the 3' sequences of MMTV genomic RNA has been demonstrated by in vitro translation studies, which have reported the synthesis of four related proteins: p36, p24, p21, and p18. These proteins are overlapping translation products of the same open reading frame, with the smaller ones initiating at internal methionine codons. From the predicted amino acid sequence of the LTR protein, we have selected a region likely to be antigenic, obtained a synthetic peptide of that region, and raised antiserum to the peptide. The antipeptide serum specifically immunoprecipitated all four proteins from in vitro translated 3' MMTV RNA, plus an additional one of 32,000 M(r). Published sequence data of MMRV LTRs show an internal AUG codon at a position which could initiate a protein of 32,000 M(r). The three smaller in vitro translation products (p24, p21, and p18) were consistently synthesized in much greater amounts than the p36 or p32 protein. The relative amount of each in vitro synthesized protein from genomic MMTV RNA could be predicted and was in good agreement with the postulated effect of flanking nucleotides on the efficiency of the respective AUG initiation codon. Polyadenylated RNAs, isolated from various mouse tissues, were selected by hybridization to plasmid DNA containing MMTV LTR sequences immobilized on nitrocellulose. In vitro translation of hybrid-selected mRNAs isolated from BALB/c mouse lactating mammary glands and carcinogen-induced mammary tumors, followed by immunoprecipitation with antipeptide serum, revealed that only one polypeptide was synthesized by the MMTV LTR-specific mRNA, the 36,000 M(r) species.

Original languageEnglish (US)
Pages (from-to)604-610
Number of pages7
JournalJournal of Virology
Volume51
Issue number3
StatePublished - 1984
Externally publishedYes

Fingerprint

Mouse mammary tumor virus
terminal repeat sequences
Terminal Repeat Sequences
translation (genetics)
Proteins
proteins
RNA
Codon
Messenger RNA
Peptides
Open Reading Frames
blood serum
codons
open reading frames
Collodion
Initiator Codon
genomics
Protein Biosynthesis
start codon
Human Mammary Glands

ASJC Scopus subject areas

  • Immunology

Cite this

@article{9f2f92e877714449bfde528fac860333,
title = "Proteins encoded by the long terminal repeat region of mouse mammary tumor virus: Identification by hybrid-selected translation",
abstract = "The long terminal repeat (LTR) region of mouse mammary tumor virus (MMTV) is known to contain an open reading frame of sufficient length to code for a protein of 36,000 M(r). The coding capacity of the 3' sequences of MMTV genomic RNA has been demonstrated by in vitro translation studies, which have reported the synthesis of four related proteins: p36, p24, p21, and p18. These proteins are overlapping translation products of the same open reading frame, with the smaller ones initiating at internal methionine codons. From the predicted amino acid sequence of the LTR protein, we have selected a region likely to be antigenic, obtained a synthetic peptide of that region, and raised antiserum to the peptide. The antipeptide serum specifically immunoprecipitated all four proteins from in vitro translated 3' MMTV RNA, plus an additional one of 32,000 M(r). Published sequence data of MMRV LTRs show an internal AUG codon at a position which could initiate a protein of 32,000 M(r). The three smaller in vitro translation products (p24, p21, and p18) were consistently synthesized in much greater amounts than the p36 or p32 protein. The relative amount of each in vitro synthesized protein from genomic MMTV RNA could be predicted and was in good agreement with the postulated effect of flanking nucleotides on the efficiency of the respective AUG initiation codon. Polyadenylated RNAs, isolated from various mouse tissues, were selected by hybridization to plasmid DNA containing MMTV LTR sequences immobilized on nitrocellulose. In vitro translation of hybrid-selected mRNAs isolated from BALB/c mouse lactating mammary glands and carcinogen-induced mammary tumors, followed by immunoprecipitation with antipeptide serum, revealed that only one polypeptide was synthesized by the MMTV LTR-specific mRNA, the 36,000 M(r) species.",
author = "Janis Racevskis and O. Prakash",
year = "1984",
language = "English (US)",
volume = "51",
pages = "604--610",
journal = "Journal of Virology",
issn = "0022-538X",
publisher = "American Society for Microbiology",
number = "3",

}

TY - JOUR

T1 - Proteins encoded by the long terminal repeat region of mouse mammary tumor virus

T2 - Identification by hybrid-selected translation

AU - Racevskis, Janis

AU - Prakash, O.

PY - 1984

Y1 - 1984

N2 - The long terminal repeat (LTR) region of mouse mammary tumor virus (MMTV) is known to contain an open reading frame of sufficient length to code for a protein of 36,000 M(r). The coding capacity of the 3' sequences of MMTV genomic RNA has been demonstrated by in vitro translation studies, which have reported the synthesis of four related proteins: p36, p24, p21, and p18. These proteins are overlapping translation products of the same open reading frame, with the smaller ones initiating at internal methionine codons. From the predicted amino acid sequence of the LTR protein, we have selected a region likely to be antigenic, obtained a synthetic peptide of that region, and raised antiserum to the peptide. The antipeptide serum specifically immunoprecipitated all four proteins from in vitro translated 3' MMTV RNA, plus an additional one of 32,000 M(r). Published sequence data of MMRV LTRs show an internal AUG codon at a position which could initiate a protein of 32,000 M(r). The three smaller in vitro translation products (p24, p21, and p18) were consistently synthesized in much greater amounts than the p36 or p32 protein. The relative amount of each in vitro synthesized protein from genomic MMTV RNA could be predicted and was in good agreement with the postulated effect of flanking nucleotides on the efficiency of the respective AUG initiation codon. Polyadenylated RNAs, isolated from various mouse tissues, were selected by hybridization to plasmid DNA containing MMTV LTR sequences immobilized on nitrocellulose. In vitro translation of hybrid-selected mRNAs isolated from BALB/c mouse lactating mammary glands and carcinogen-induced mammary tumors, followed by immunoprecipitation with antipeptide serum, revealed that only one polypeptide was synthesized by the MMTV LTR-specific mRNA, the 36,000 M(r) species.

AB - The long terminal repeat (LTR) region of mouse mammary tumor virus (MMTV) is known to contain an open reading frame of sufficient length to code for a protein of 36,000 M(r). The coding capacity of the 3' sequences of MMTV genomic RNA has been demonstrated by in vitro translation studies, which have reported the synthesis of four related proteins: p36, p24, p21, and p18. These proteins are overlapping translation products of the same open reading frame, with the smaller ones initiating at internal methionine codons. From the predicted amino acid sequence of the LTR protein, we have selected a region likely to be antigenic, obtained a synthetic peptide of that region, and raised antiserum to the peptide. The antipeptide serum specifically immunoprecipitated all four proteins from in vitro translated 3' MMTV RNA, plus an additional one of 32,000 M(r). Published sequence data of MMRV LTRs show an internal AUG codon at a position which could initiate a protein of 32,000 M(r). The three smaller in vitro translation products (p24, p21, and p18) were consistently synthesized in much greater amounts than the p36 or p32 protein. The relative amount of each in vitro synthesized protein from genomic MMTV RNA could be predicted and was in good agreement with the postulated effect of flanking nucleotides on the efficiency of the respective AUG initiation codon. Polyadenylated RNAs, isolated from various mouse tissues, were selected by hybridization to plasmid DNA containing MMTV LTR sequences immobilized on nitrocellulose. In vitro translation of hybrid-selected mRNAs isolated from BALB/c mouse lactating mammary glands and carcinogen-induced mammary tumors, followed by immunoprecipitation with antipeptide serum, revealed that only one polypeptide was synthesized by the MMTV LTR-specific mRNA, the 36,000 M(r) species.

UR - http://www.scopus.com/inward/record.url?scp=0021180195&partnerID=8YFLogxK

UR - http://www.scopus.com/inward/citedby.url?scp=0021180195&partnerID=8YFLogxK

M3 - Article

VL - 51

SP - 604

EP - 610

JO - Journal of Virology

JF - Journal of Virology

SN - 0022-538X

IS - 3

ER -