[Ability of the cells of intra- and interspecific hybrids of murine hepatoma XXIIa to synthesize the serum proteins albumin and transferrin].

Independent hybrid clones resulted from the whole cell and microcell-mediated transfer of hamster or mouse fibroblast chromosomes into mouse hepatoma XXIIa cells. The fusion was promoted with PEG, ethidium bromide alone, or in combination with HAT and ouabain, was used for selecting the hybrids. Using indirect immunoautoradiography, three clones (one intra- and one interspecies microcellular; one interspecies, whole cell fusion) have been found to express their hepatic function to synthesize transferrin. The liver specific protein--albumin--was extinguished in all the hybrid combinations. Possible mechanisms of gene expression are discussed. The hybrids selected could be used for mapping chromosomes, coding proteins, as well as for studying regulation in the tandem of albumin and alpha-fetoprotein genes in the mouse genome. The microcell mediated chromosome transfer into differentiated cells has been used to construct original genetical combinations of regulatory and structural elements of the mouse genome.