Abstract:
:Antibody specific for the native form of Chinese hamster hypoxanthine/guanine phosphoribosyltransferase (HPRT; IMP:pyrophosphate phosphoribosyltransferase, EC 2.4.2.8) was used to detect the synthesis of HPRT protein in a rabbit reticulocyte lysate translation system primed with mRNA from Chinese hamster tissues and cultured cells. Electrophoretic analysis of the immunopurified products from the translation of mRNA from wild-type and a series of mutant Chinese hamster cells indicated that HPRT synthesis in vitro qualitatively and quantitatively corresponded to synthesis in vivo. The translation system was used to identify two mRNA sources producing high levels of HPRT protein: Chinese hamster brain and a mouse neuroblastoma HPRT revertant cell line, NBR4. Translation of NBR4 mRNA generated 25-50 times more HPRT protein than mRNA from wild-type cells. The basis for HPRT overproduction is considered in view of an X chromosome alteration found in NBR4 cells.
journal_name
Proc Natl Acad Sci U S Aauthors
Melton DW,Konecki DS,Ledbetter DH,Hejtmancik JF,Caskey CTdoi
10.1073/pnas.78.11.6977subject
Has Abstractpub_date
1981-11-01 00:00:00pages
6977-80issue
11eissn
0027-8424issn
1091-6490journal_volume
78pub_type
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