Open Access. Powered by Scholars. Published by Universities.®
- Discipline
Articles 1 - 2 of 2
Full-Text Articles in Medicine and Health Sciences
In Vitro Enzymatic Assay Of Rna Methylation, Pamela Jean Eubanks Gallup
In Vitro Enzymatic Assay Of Rna Methylation, Pamela Jean Eubanks Gallup
Chemistry & Biochemistry Theses & Dissertations
An assay procedure for in vitro enzymatic methylation of mannnalian ribosomal RNA has been developed in this study. The assay procedure, utilized for the comparison of normal and neoplastic methylase activities (using mouse liver and Ehrlich ascites cells as sources of enzyme), is a modification of previously published methods (52,53). A 100,000 x g supernatant (SlOO) enzyme preparation was incubated with 28S-5.8S rRNA and tritium-labeled S-adenosyl-L-methionine. The RNA was extracted, applied to DEAE cellulose paper, washed, and the radioactivity counted. The neoplastic cell methylase preparation was more active in methylating both exogenous neoplastic and normal 28S-5.8S rRNA than the normal …
The Analysis Of S-Adenosylmethionine And S-Adenosylhomocysteine In Normal And Neoplastic Cells, Kathryn Elizabeth Godburn
The Analysis Of S-Adenosylmethionine And S-Adenosylhomocysteine In Normal And Neoplastic Cells, Kathryn Elizabeth Godburn
Chemistry & Biochemistry Theses & Dissertations
Altered patterns of methylation have been shown in both ribosomal and transfer RNA isolated from cancer cells. In contrast to the elevated activity of the methyltransferases responsible for this modification, hypomethylation appears as a general characteristic. The endogenous levels of S-adenosylmethionine and S-adenosylhomocysteine are important in relationship to their role as substrate and product of the transmethylation reaction. The levels of S-adenosylmethionine and S-adenosylhomocysteine were determined using phosphocellulose cation exchange or high pressure liquid chromatography. High voltage paper electrophoresis was used in a modified procedure to directly resolve (35s) labeled S-adenosylmethionine and S-adenosylhomocysteine in small quantities of cell …