Amplification and expression of phenylalanine hydroxylase in mouse erythroleukemia cells.
A cell line, CY-1, was selected in tyrosine free (tyr-) medium after fusion of mouse erythroleukemia (MEL) cells with mitomycin C-treated rat hepatoma cells. MEL cells do not express the enzyme phenylalanine hydroxylase (PH) and are unable to grow in tyr- medium, whereas the rat hepatoma cells constitutively express PH and are able to grow in tyr- medium. CY-1 cells resemble MEL cells morphologically, karyotypically, and in being inducible for hemoglobin synthesis. In contrast to MEL cells, CY-1 expresses PH and is therefore able to grow in tyr- medium. Using a rat cDNA probe for the PH gene, Southern blot analyses were carried out on DNA isolated from CY-1 and parental cells. CY-1 showed the characteristic mouse PH gene pattern but the gene copy number was amplified four- to eightfold compared to parental MEL cells.
Brown
R M
RM
James
R
R
Cotton
R G
RG
D000818:Animals; D002459:Cell Fusion; D002460:Cell Line; D003470:Culture Media; D004262:DNA Restriction Enzymes; D004273:DNA, Neoplasm / Q000235:genetics; D004587:Electrophoresis, Agar Gel; D005784:Gene Amplification; D005786:Gene Expression Regulation; D004915:Leukemia, Erythroblastic, Acute / Q000201:enzymology* / Q000235:genetics; D008114:Liver Neoplasms, Experimental / Q000201:enzymology / Q000235:genetics; D051379:Mice; D009693:Nucleic Acid Hybridization; D010651:Phenylalanine Hydroxylase / Q000235:genetics*; D051381:Rats
D003470:Culture Media; D004273:DNA, Neoplasm; D010651:Phenylalanine Hydroxylase; D004262:DNA Restriction Enzymes