| First Author | Ye H | Year | 1999 |
| Journal | Mol Cell Biol | Volume | 19 |
| Issue | 12 | Pages | 8570-80 |
| PubMed ID | 10567581 | Mgi Jnum | J:58603 |
| Mgi Id | MGI:1349265 | Doi | 10.1128/mcb.19.12.8570 |
| Citation | Ye H, et al. (1999) Premature expression of the winged helix transcription factor HFH-11B in regenerating mouse liver accelerates hepatocyte entry into S phase. Mol Cell Biol 19(12):8570-80 |
| abstractText | Two-thirds partial hepatectomy (PH) induces differentiated cells in the liver remnant to proliferate and regenerate to its original size. The proliferation-specific HNF-3/fork head homolog-11B protein (HFH-11B; also known as Trident and Win) is a family member of the winged helix/fork head transcription factors and in regenerating liver its expression is reactivated prior to hepatocyte entry into DNA replication (S phase). To examine whether HFH-11B regulates hepatocyte proliferation during liver regeneration, we used the -3-kb transthyretin (TTR) promoter to create transgenic mice that displayed ectopic hepatocyte expression of HFH-11B. Liver regeneration studies with the TTR-HFH-11B mice demonstrate that its premature expression resulted in an 8-h acceleration in the onset of hepatocyte DNA replication and mitosis. This liver regeneration phenotype is associated with protracted expression of cyclin D1 and C/EBPbeta, which are involved in stimulating DNA replication and premature expression of M phase promoting cyclin B1 and cdc2. Consistent with the early hepatocyte entry into S phase, regenerating transgenic livers exhibited earlier expression of DNA repair genes (XRCC1, mHR21spA, and mHR23B). Furthermore, in nonregenerating transgenic livers, ectopic HFH-11B expression did not elicit abnormal hepatocyte proliferation, a finding consistent with the retention of the HFH-11B transgene protein in the cytoplasm. We found that nuclear translocation of the HFH-11B transgene protein requires mitogenic signalling induced by PH and that its premature availability in regenerating transgenic liver allowed nuclear translocation to occur 8 h earlier than in wild type. |
