Quantitation of endogenous liver apolipoprotein B mRNA editing.
The mRNA for apolipoprotein B is translated into either a high molecular weight (apo BH) or low molecular weight (apo BL) form of the protein depending on a novel form of RNA processing known as RNA editing. Apo BH mRNA editing is both tissue-specific and hormonally regulated and involves transition of cytidine to uridine at codon 2153 thereby converting a glutamine codon (CAA) to a translational stop codon (UAA). Three methods for quantitating the endogenous levels of liver apo B mRNA editing were compared: (1) Southern blot hybridization with discriminative thermal washes, (2) competimer-hybridization with discriminative thermal washes and (3) competimer-polymerase chain reaction (competimer-PCR). The data suggest that hybridization and PCR can yield similar quantitation when competing oligonucleotides are used. Based on competimer-PCR it is proposed that 40% and 85% of normal rat liver and small intestine apo B mRNA (respectively) are edited.
Backus
J W
JW
Department of Biochemistry, University of Rochester, NY 14642.
Eagleton
M J
MJ
Harris
S G
SG
Sparks
C E
CE
Sparks
J D
JD
Smith
H C
HC
D000818:Animals; D001055:Apolipoproteins B / Q000235:genetics*; D001483:Base Sequence; D007421:Intestine, Small / Q000378:metabolism; D008099:Liver / Q000378:metabolism*; D008969:Molecular Sequence Data; D009838:Oligodeoxyribonucleotides; D016133:Polymerase Chain Reaction; D012333:RNA, Messenger / Q000378:metabolism*; D051381:Rats
D001055:Apolipoproteins B; D009838:Oligodeoxyribonucleotides; D012333:RNA, Messenger