High mobility group chromosomal proteins isolated from muclei and cytosol of cultured hepatoma cells are similar.
Using sequential chromatography on columns containing immobilized double-stranded DNA and single-stranded DNA, we have purified a protein from the cytosol of an established line of cultured rat hepatoma cells that, by several criteria, is a high mobility group (HMG) protein. Analyses of DNA binding properties, electrophoretic mobilities, amino acid compositions, and immunochemical reactivities reveal that the cytosolic protein is the same protein as HMG-1 isolated from the purified chromatin of the same cell line. Thus, authentic HMG-1 appears to be at least partially responsible for the cytoplasmic fluorescence observed when mammalian cells are stained with fluorescece observed when mammalian cells are stained with fluorescent-labeled, affinity-purified antibodies against HMG-1 [Bustin, M., & Neihart, N.K. (1979) Cell 16, 181-189]. We suggest that HMG-1 cn shuttle between nucleus and cytoplasm, perhaps in response to the nucleus' need for helix destabilizing proteins.
D000596:Amino Acids / Q000032:analysis; D000818:Animals; D002417:Cattle; D002460:Cell Line; D002467:Cell Nucleus / Q000032:analysis*; D002846:Chromatography, Affinity; D002868:Chromosomal Proteins, Non-Histone / Q000302:isolation & purification*; D003168:Complement Fixation Tests; D003600:Cytosol / Q000032:analysis; D004247:DNA; D000939:Epitopes; D006609:High Mobility Group Proteins; D006801:Humans; D008114:Liver Neoplasms, Experimental / Q000032:analysis*; D008970:Molecular Weight; D051381:Rats; D013950:Thymus Gland
D000596:Amino Acids; D002868:Chromosomal Proteins, Non-Histone; D000939:Epitopes; D006609:High Mobility Group Proteins; D004247:DNA