| First Author | Islam R | Year | 2014 |
| Journal | J Cell Physiol | Volume | 229 |
| Issue | 4 | Pages | 443-52 |
| PubMed ID | 24037986 | Mgi Jnum | J:316494 |
| Mgi Id | MGI:6835975 | Doi | 10.1002/jcp.24462 |
| Citation | Islam R, et al. (2014) Pin1-mediated prolyl isomerization of Runx1 affects PU.1 expression in pre-monocytes. J Cell Physiol 229(4):443-52 |
| abstractText | Regulation of the hematopoietic transcription factor PU.1, a member of the ETS family, plays a critical role in the development of blood cells and in leukemia. The dosage of PU.1 has been shown to cause a shift in myelomonocytic progenitor fate. Pin1 is a unique substrate-specific enzyme that can isomerize phospho-Ser/Thr-Pro peptide bonds, accelerating the conformational change in its substrates between a cis and a trans form. Such activity has been demonstrated to be a tightly controlled mechanism regulating a wide variety of protein functions under both normal physiological and pathological conditions. We have previously reported that a conformational change in Runx2 induced by Pin1 is essential for its function in osteogenesis in vitro and in vivo. In this study, we show that the Pin1-mediated conformational change in Runx1 enhances its acetylation and stabilization and, consequently, enhances its transacting activity. The increased acetylation of Runx1 represses PU.1 transcription in pre-monocytes. Conversely, the lack of (or the inhibition of) Pin1 increases PU.1 transcription in vitro and in vivo in pre-monocytes and in the spleen tissue. Pin1 KO mice have an increased CD11b(+) /F4/80(+) cell population and F4/80 protein expression in spleen. From our data, we can conclude that the conformational change in Runx1 induced by Pin1 represses PU.1 transcription in pre-monocytes and influences the commitment to the monocyte lineage. The dosage of PU.1 is a crucial factor in acute myeloid leukemia (AML), and Pin1 may thus be a useful target for controlling PU.1-dependent hematopoiesis, as well as leukemogenesis. |
