These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Characterization of somatic cell hybrids exhibiting extinction of AFP, albumin and an AFP-HPRT transgene.
    Author: Keherly MJ, Hsieh CC, McCombs JL, Merryman LS, Papaconstantinou J.
    Journal: Somat Cell Mol Genet; 1996 Mar; 22(2):119-34. PubMed ID: 8782491.
    Abstract:
    We utilized an AFP-HPRT transgene, i.e. the HPRT coding sequences under the regulation of AFP enhancer and promoter sequences, to localize the AFP extinguisher locus in intertypic somatic cell hybrids (hepatoma X fibroblast). This hybrid gene construct, which directly links AFP regulation to a reversibly selective gene, enabled the selection of stably transfected cells which express AFP, as well as cells showing extinction of AFP. Mouse hepatoma cells stably transfected with and expressing the transgene were fused to human fibroblasts, and the resulting somatic cell hybrids were characterized using Southern, Northern and karyotypic analyses. That several hybrids exhibited the proper extinction of AFP, AFP-HPRT and albumin suggests coregulation of these genes by an extinguisher. Segregant lines derived from these hybrids were selected for the loss of extinguisher activity and for reexpression of the transgene. Karyotypic analysis of hybrid and segregant lines, exhibiting proper AFP, albumin and AFP-HPRT phenotypes, revealed that the presence of human chromosome 7 was most closely associated with the AFP-extinguished state. The hybrids generated in these studies now make it possible to isolate the sequences responsible for AFP and albumin extinction.
    [Abstract] [Full Text] [Related] [New Search]