The expression of @entity8151 can be modulated by mRNA editing, a unique posttranscriptional base change in the @entity8151 mRNA. @entity8151 -48, the translation product of edited @entity8151 mRNA, is not a precursor of the atherogenic low density lipoproteins and lipoprotein(a). In @entity1 and various other mammals, the @entity8151 mRNA is edited in the intestine but not in the liver, which exclusively secretes @entity8151 -100-containing lipoproteins as precursors for low density lipoprotein formation. In species such as the @entity35 , @entity19 , @entity235 , and @entity1641 , @entity8151 mRNA is also edited in the liver, resulting in low plasma levels of low density lipoprotein. Editing of the @entity8151 mRNA is mediated by the @entity8151 mRNA-editing enzyme complex, of which the catalytic subunit @entity69098 is not expressed in the liver of species without hepatic editing. To understand the molecular basis for liver-specific expression of @entity69098 and the editing of hepatic @entity8151 mRNA, the expression pattern and genomic organization of the @entity35 @entity69098 gene have been characterized. The @entity35 @entity69098 gene contains 6 exons and 2 promoters with distinct activities. The expression of @entity69098 in the @entity35 liver is the result of a promoter located upstream, with tissue-specific exon use and alternate splicing within the 5'-untranslated region of @entity69098 mRNA encoded by exon 2. In addition to the liver, this promoter also induces @entity69098 expression in the spleen, lung, kidney, @entity2057 . The promoter located downstream belongs to a new class of TATA-less promoters and is responsible for the abundant expression of @entity69098 in the intestine. Mapping of the transcriptional start sites and deletion analysis of the promoter regions by using luciferase as the reporter gene have defined the regulatory elements of both promoters. The downstream, intestine-specific promoter contains a negative regulatory element between -1100 and -500, which appears to restrict its activity to the intestine. The upstream, liver-specific promoter of the @entity35 @entity69098 gene induces @entity69098 expression and editing of @entity8151 mRNA in @entity1 @entity157 @entity5959 and Hep G2 cells. Understanding the molecular basis for the liver-specific expression of @entity69098 in the @entity35 promises new strategies to induce @entity69098 expression in the @entity1 liver for the reduction of atherogenic lipoprotein levels by hepatic @entity8151 mRNA editing.

Distinct promoters induce @entity69098 expression in XXXX liver and intestine.

@entity1 :: ('9606', 'Species') :: ['humans', 'human'] @entity1641 :: ('9796', 'Species') :: ['horse'] @entity235 :: ('9615', 'Species') :: ['dog'] @entity19 :: ('10090', 'Species') :: ['mouse'] @entity69098 :: ('25383(Tax:10116)', 'Gene') :: ['APOBEC-1'] @entity5959 :: ('284424', 'Gene') :: ['HuH-7'] @entity157 :: ('MESH:D006528', 'Disease') :: ['hepatoma'] @entity35 :: ('10116', 'Species') :: ['rat'] @entity8151 :: ('54225(Tax:10116)', 'Gene') :: ['apolipoprotein (apo) B', 'apo B', 'Apo B'] @entity2057 :: ('MESH:D009133', 'Disease') :: ['heart, and skeletal muscle']
@entity35 :: (10116,Species) :: ['rat']
