PMID- 169380 OWN - NLM STAT- MEDLINE DCOM- 19751120 LR - 20031114 IS - 0027-8874 (Print) IS - 0027-8874 (Linking) VI - 55 IP - 2 DP - 1975 Aug TI - Mouse mammary tumor virus polypeptide precursors in intracytoplasmic A particles. PG - 493-6 AB - Intracytoplasmic A particles were analyzed by immunodiffusion and sodium dodecyl sulfate--polyacrylamide gel electrophoresis (SDS--PAGE) before and after enzymatic cleavage with trypsin. A common antigen in A particles was detected by antisera prepared against purified intracytoplasmic A particles, purified mouse mammary tumor virus (MMTV), and a purified MMTV core polypeptide (p28). Despite this correlation, no SDS--polyacrylamide band migrating at p28 was observed in purified intracytoplasmic A particles. However, after incubation with trypsin, A particles subjected to SDS--PAGE produced only two polypeptide bands. They were observed at p28 and p15-10. Ouchterlony analysis of the trypsin-cleaved A particles revealed no alteration in the antigenicity of the particles. These results suggested that some structural components of intracytoplasmic A particles are polypeptide precursors of MMTV core proteins. FAU - Smith, G H AU - Smith GH FAU - Lee, B K AU - Lee BK LA - eng PT - Journal Article PL - United States TA - J Natl Cancer Inst JT - Journal of the National Cancer Institute JID - 7503089 RN - 0 (Antigens) RN - 0 (Viral Proteins) SB - IM MH - Animals MH - Antigens MH - Cells, Cultured MH - Cross Reactions MH - Female MH - Inclusion Bodies, Viral/analysis/immunology/*metabolism MH - Mammary Tumor Virus, Mouse/*growth & development/immunology MH - Mice MH - Mice, Inbred C3H MH - Viral Proteins/analysis/immunology/*metabolism EDAT- 1975/08/01 00:00 MHDA- 1975/08/01 00:01 CRDT- 1975/08/01 00:00 PHST- 1975/08/01 00:00 [pubmed] PHST- 1975/08/01 00:01 [medline] PHST- 1975/08/01 00:00 [entrez] PST - ppublish SO - J Natl Cancer Inst. 1975 Aug;55(2):493-6.