Expression of apolipoprotein B mRNAs encoding higher- and lower-molecular weight isoproteins in rat liver and intestine

摘要: Abstract Two B apolipoproteins (apo) are present in human plasma, designated apoB-100 and apoB-48, represent translational products from mature apoB mRNAs that differ by a single base. Either the glutamine codon encoded single-copy gene at nucleotide 6666 is transcribed translated to produce or an RNA-editing mechanism substitutes uracil for cytosine, altering this (CAA) stop (UAA), prematurely terminating translation apoB-48. In report, editing of rat transcripts was evaluated amplification RNA with polymerase chain reaction use primers based on cDNA cloned liver library. The combined results study show (i) copy exists rat; (ii) encodes only synthesis higher molecular weight (apoBH); (iii) undergo editing; (iv) apoBH lower (apoBL) structural equivalents apoB-48 humans, respectively; (v) occurs both intestine (vi) hepatic more extensively edited than RNA, which consistent marked increase apoBL secretion when compared human; (vii) definitive identification mRNA as well provides biosynthesis intestine.