ZONAL DISTRIBUTION OF TRANSCRIPTS OF 4 HEPATIC TRANSCRIPTION FACTORS IN THE MATURE RAT-LIVER

Within the liver acinus the majority of genes are expressed in an asce nding or descending gradient from the portal to the central vein. The regulatory factors involved in this spatial pattern of gene expression are still poorly understood. Many liver genes are regulated by liver- enriched transcription factors. Here we report on mRNA distribution of four transcription factors in cell lysates obtained from either the p eriportal or the perivenous region after zone-specific digitonin infus ion and by in-situ hybridization. Northern blot analysis revealed that there were slightly more transcripts of C/EBP, HNF1 beta (n.s.) and H NF4 (p < 0.05), but fewer of HNF3 gamma (n.s.), in perivenous than in periportal lysates. A somewhat stronger staining in the perivenous reg ion of HNF4 was also seen by in-situ hybridization. The moderate acina r zonation of the mRNAs of these transcription factors suggests that a t best they could modulate but not govern the zonated expression of li ver genes in the mature liver.