ISSN:
0021-9541
Keywords:
Life and Medical Sciences
;
Cell & Developmental Biology
Source:
Wiley InterScience Backfile Collection 1832-2000
Topics:
Biology
,
Medicine
Notes:
A large collection (105) of mouse L cell mutants lacking hypoxanthine-guanine phosphoribosyl transferase activity (HGPRT; E. C. 2.4.2.8) were analyzed for the presence of serologically cross reacting material (CRM). Antibody directed against highly purified mouse liver HGPRT was used for detecting CRM activity by two methods: (1) the standard precipitation-inhibition assay; and (2) a radioimmune-precipitation assay. The latter assay proved to have far greater sensitivity for the detection of altered forms of HGPRT. Approximately 40% of the HGPRT- cell lines contain CRM activity (i.e., were CRM+). This indicates that a minimum of 40% of the HGPRT- clones arose as a result of mutations in the HGPRT structural gene. The CRM+ cell lines were shown to contain different levels of CRM activity. Measurements of the heat sensitivity of CRM in the different HGPRT- cell lines showed a broad spectrum of CRM heat inactivation kinetics. These latter two observations provide strong evidence that the mutations giving rise to the HGPRT-CRM+ phenotype occurred at different sites in the HGPRT structural gene.
Additional Material:
7 Ill.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1002/jcp.1040850217
