APOLIPOPROTEIN-B MESSENGER-RNA EDITING IS DEVELOPMENTALLY REGULATED IN PIG SMALL-INTESTINE - NUCLEOTIDE COMPARISON OF APOLIPOPROTEIN-B EDITING REGIONS IN 5 SPECIES

Apolipoprotein B (apo B) mRNA undergoes a posttranscriptioonal tissue-specific editing reaction which changes codon 2153 from glutamine (CAA) in apoB-100 mRNA to an in-frame stop codon (UAA) in apoB-48 mRNA. Small intestinal apo B mRNA was found to be predominantly (>90%) unedited in fetal (40-day gestatonal age) piglets but >95% edited in neonatal, suckling and adult animals. By contrast, both fetal, neonatal and adult pig liver contained >99% unedited, apo B-100 mRNA. The nucleotide sequence spanning the edited region in apo B mRNA was found to be highly conserved. We speculate that the regulation of apo B mRNA editing may be developmentally modulated in pig small intestine. © 1990 Academic Press, Inc.