Hypoxanthine guanine phosphoribosyltransferase (HGPRT) activity in hybrids derived from HGPRT+ and HGPRT- mouse cells
Siroký, J.; Spurná, V.
Neoplasma 22(4): 403-412
1975
ISSN/ISBN: 0028-2685 PMID: 1196424 Document Number: 84584
By utilizing the selection system, a population of hybrid cells with the gene coding HGPRT and sensitive to 8-azaguanine (8-AG) was isolated from a mixed population of hybrid cells derived from malignant diploid HGPRT+ mouse lymphosarcoma cells (LS/BL) and L cells resistant to 8-AG (HGPRT-, R-AG/20 strain). During back-selection of this hybrid population , cultivated in vitro, HGPRT- negative fractions of the cell population, resistant to 8-AG, appeared in a high frequency. As a rule, the telocentric chromosomes (or chromosome), originated from the HGPRT+ parental cells (LS/BL), were lost in these cells. The X chromosome of the LS/BL cells coding the HGPRT enzyme was not present in all cells of the hybrid HGPRT+ population. Hence it is assumed that the fusion of HGPRT+ (LS/BL) and HGPRT- (R-AG/20) cells resulted in a reexpression of the HGPRT activity from the R-AG/20 parental cells.