OBJECTIVETo explore the mechanism of transcription regulation of the liver-selective genes responsible for cell communication.

METHODSTissue-selective Affymetrix probe sets (3919 probes in total) were clustered by functional categories. Liver-selective cell communication (LSCC) genes were selected for further analysis. The 500-bp upstream sequences of all the LSCC genes were extracted for predicting the transcription factor binding sites (TFBS) of known transcription factors (TFs) using 3 programs; literature mining was then performed for these LSCC genes and TFs, and the transcription regulatory network were constructed.

RESULTSThe binding sites of 50 and 72 transcription factors were predicted from the upstream sequences of 23 LSCC genes by two programs respectively. Among them, 18 transcription factors were found in common. The top 10 TFBS sequences were basically consistent to the predicted TFs. Literature mining indicated that LSCC genes and TFs were closely related to such terms as albumin, diabetes, glucose, lipid, metabolism, and JNK, in addition to those associated with hepatic tissue and TFs. These observations suggested that LSCC genes and TFs were involved in the regulation of glucose and lipid metabolism, binding and transport, coagulation signal cascades, inflammatory response, etc. PPP2R1B, which was out of the network, showed a partial functional similarity to DUSP10 in the network.

CONCLUSIONSLSCC genes and the predicted TFs may be involved in the regulation of many important functions of the liver, which are integrated into a sophisticated transcription regulatory network. JUN may be the key target for regulation, and PPP2R1B is presumed to participate in the regulation of JUN.