Phosphorylation and O-linked glycosylation of Elf-1 leads to its translocation to the nucleus and binding to the promoter of the TCR zeta-chain.
Elf-1, a member of the E 26-specific transcription factor family with a predicted molecular mass of 68 kDa, is involved in the transcriptional regulation of several hematopoietic cell genes. We demonstrate that Elf-1 exists primarily as a 98-kDa form in the nucleus and as an 80-kDa form in the cytoplasm. Phosphorylation and O-linked glycosylation contribute to the increased posttranslational molecular mass of Elf-1. The 98-kDa Elf-1 is released from the cytoplasm tethering retinoblastoma protein and moves to the nucleus, where it binds to the promoter of the TCR zeta-chain gene. Finally, the cytoplasmic 98-kDa form enters the proteasome pathway and undergoes degradation. In conclusion, different forms of Elf-1 are the products of posttranslational modifications that determine its subcellular localization, activity, and metabolic degradation.
Juang
Yuang-Taung
YT
Department of Medicine, Uniformed Services University of the Health Sciences, Bethesda, MD 20814, USA.
Solomou
Elena E
EE
Rellahan
Barbara
B
Tsokos
George C
GC
D000117:Acetylglucosamine / Q000378:metabolism; D021581:Active Transport, Cell Nucleus / Q000235:genetics; D001665:Binding Sites / Q000235:genetics; D002236:Carbohydrate Conformation; D002467:Cell Nucleus / Q000378:metabolism*; D002478:Cells, Cultured; D003546:Cysteine Endopeptidases / Q000378:metabolism; D003593:Cytoplasm / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000096:biosynthesis / Q000378:metabolism*; D006031:Glycosylation; D006801:Humans; D019169:Jurkat Cells; D008565:Membrane Proteins / Q000235:genetics* / Q000378:metabolism*; D008970:Molecular Weight; D009097:Multienzyme Complexes / Q000378:metabolism; D010766:Phosphorylation; D011401:Promoter Regions, Genetic; D046988:Proteasome Endopeptidase Complex; D011485:Protein Binding / Q000235:genetics; D020033:Protein Isoforms / Q000378:metabolism; D011493:Protein Kinase C / Q000037:antagonists & inhibitors / Q000378:metabolism; D011948:Receptors, Antigen, T-Cell / Q000235:genetics* / Q000378:metabolism*; D013601:T-Lymphocytes / Q000201:enzymology / Q000378:metabolism; D014157:Transcription Factors / Q000096:biosynthesis / Q000378:metabolism*
D004268:DNA-Binding Proteins; D008565:Membrane Proteins; D009097:Multienzyme Complexes; D020033:Protein Isoforms; D011948:Receptors, Antigen, T-Cell; D014157:Transcription Factors; C054979:antigen T cell receptor, zeta chain; D011493:Protein Kinase C; D003546:Cysteine Endopeptidases; D046988:Proteasome Endopeptidase Complex; D000117:Acetylglucosamine