| First Author | Liang H | Year | 1996 |
| Journal | Arch Biochem Biophys | Volume | 330 |
| Issue | 2 | Pages | 259-65 |
| PubMed ID | 8660654 | Mgi Jnum | J:34403 |
| Mgi Id | MGI:81864 | Doi | 10.1006/abbi.1996.0251 |
| Citation | Liang H, et al. (1996) Ubiquitous expression and cell cycle regulation of the protein kinase PIM-1. Arch Biochem Biophys 330(2):259-65 |
| abstractText | The murine pim-1 gene, isolated as a locus frequently activated by proviral integration in T cell lymphomas, encodes a protein serine kinase. Although genetic evidence suggests a crucial role for this protooncogene in cell growth and transformation, very little is known about its protein product. The murine pim-1 mRNA provides alternate translational starts at a CUG codon +87-89 and an AUG codon at +339-341, in the same open reading frame (ORF), resulting in 44-kDa (397 amino acids) and 34-kDa (313 amino acids) isoforms. In this report, we demonstrate that the human PIM-1 mRNA is translated only from the single initiation methionine codon at +339-341 under cell-free conditions. Immunoblotting analyses of several human solid tumor cell lines, with highly specific antisera reveal two ubiquitously expressed isoforms (35 and 34 kDa). The estimated half-life of these proteins is shorter in the normal peripheral blood leukocytes (<5 min) than in the chronic myelogenous leukemia cells K562 (<20 min). Immunoblotting analyses of centrifugally elutriated fractions of the chronic myelogenous leukemia BV173 cells demonstrate that the levels of PIM-1 increase during the progression from early to late GI, remain high at the G1/S boundary and G2 phases of the cell cycle. The results presented here suggest a ubiquitous role for PIM-1 in progression through cell cycle. |
