A complex containing polypyrimidine tract-binding protein is involved in regulating the stability of CD40 ligand (CD154) mRNA.

摘要: CD40 ligand (CD154) expression has been shown to be regulated, in part, at the posttranscriptional level by a pathway of "regulated instability" mRNA decay throughout time course T cell activation. This is modulated late times activation binding stability complex (termed I) CU-rich region 3' untranslated CD154 message. We have undertaken experiments extend these findings and analyze cis-acting elements trans-acting factors involved this regulation. previously that minimal sequence for I 63 nt motif. However, our current study shows when site was deleted additional observed upstream downstream region. Only after deletion an extended Delta1515) completely abolished. Analysis using competition revealed three adjacent regions bound related but not identical complexes. all sites appeared 55-kDa protein as RNA-binding protein. Deletion Delta1515 resulted reduced transcript measured both vitro vivo assays. Finally, Abs against known proteins, we identified polypyrimidine tract-binding (or heterogeneous nuclear ribonucleoprotein candidate component I.