V-myc- and c-myc-encoded proteins are associated with the nuclear matrix.
A series of extraction procedures were applied to avian nuclei which allowed us to define three types of association of v-myc- and c-myc-encoded proteins with nuclei: (i) a major fraction (60 to 90%) which is retained in DNA- and RNA-depleted nuclei after low- and high-salt extraction, (ii) a small fraction (1%) released during nuclease digestion of DNA in intact nuclei in the presence of low-salt buffer, and (iii) a fraction of myc protein (less than 10%) extractable with salt or detergents and found to have affinity for both single- and double-stranded DNA. Immunofluorescence analysis with anti-myc peptide sera on cells extracted sequentially with nucleases and salts confirmed the idea that myc proteins were associated with a complex residual nuclear structure (matrix-lamin fraction) which also contained avian nuclear lamin protein. Dispersal of myc proteins into the cytoplasm was found to occur during mitosis. Both c-myc and v-myc proteins were associated with the matrix-lamin, suggesting that the function of myc may relate to nuclear structural organization.
D000818:Animals; D002467:Cell Nucleus / Q000032:analysis / Q000648:ultrastructure*; D002472:Cell Transformation, Viral; D004268:DNA-Binding Proteins / Q000032:analysis; D003851:Deoxyribonucleases; D015683:Gene Products, gag; D034882:Lamins; D008970:Molecular Weight; D009698:Nucleoproteins / Q000378:metabolism; D009857:Oncogenes; D009994:Osmolar Concentration; D011784:Quail; D012260:Ribonucleases; D014764:Viral Proteins / Q000378:metabolism*
D004268:DNA-Binding Proteins; D015683:Gene Products, gag; D034882:Lamins; D009698:Nucleoproteins; D014764:Viral Proteins; D003851:Deoxyribonucleases; D012260:Ribonucleases