Abstract:
:Prototrophic hybrids formed from an adenine-requiring Chinese hamster cell and human fibroblasts uniformly display new esterase activity that differs from that of either parental cell in electrophoretic mobility and substrate specificity. The hybrids that grew in the selective medium and possessed the new esterase activity had a single extra chromosome that resembled a B-group human chromosome. When clones of such hybrid cells were cultured in nonselective medium, they rapidly reverted to inability to synthesize adenine, disappearance of the new esterase activity, and simultaneous loss of the extra human chromosome. Esterase activity like that of the hybrid is present in cells of various Chinese hamster, but not human, tissues. It is postulated that particular Chinese hamster esterase genes became inactive after longterm cultivation, and that, in the hybrid cell, a human activator gene linked to the adeB gene and located on a human B-group chromosome reactivated expression of these Chinese hamster esterase genes.
journal_name
Proc Natl Acad Sci U S Aauthors
Kao FT,Puck TTdoi
10.1073/pnas.69.11.3273subject
Has Abstractpub_date
1972-11-01 00:00:00pages
3273-7issue
11eissn
0027-8424issn
1091-6490journal_volume
69pub_type
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