Phosphorylated Ser/Arg-rich proteins: limiting factors in the assembly of 200S large nuclear ribonucleoprotein particles
| Autor: | Joseph Sperling, Shmuel Yitzhaki, Elana Miriami, Ruth Sperling |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 1996 |
| Předmět: |
RNA Splicing
RNA-binding protein Biology Heterogeneous ribonucleoprotein particle Ligases Splicing factor SR protein Protein splicing Cricetinae Aspartate Carbamoyltransferase Animals Humans Phosphorylation Dihydroorotase Ribonucleoprotein Cell Nucleus Multidisciplinary Nuclear Proteins RNA-Binding Proteins Phosphoproteins Ribonucleoproteins Small Nuclear Splicing Factor U2AF Precipitin Tests Cell biology DNA-Binding Proteins Biochemistry Ribonucleoproteins RNA splicing Small nuclear ribonucleoprotein Research Article HeLa Cells Polypyrimidine Tract-Binding Protein Protein Binding |
| Popis: | We have previously shown that specific nuclear pre-mRNA transcripts and their splicing products, as well as the general population of nuclear poly(A)+ RNA, are packaged in large nuclear ribonucleoprotein (InRNP) particles that sediment at the 200S region in sucrose gradients. The InRNP particles contain all uridine-rich small nuclear ribonucleoprotein complexes required for pre-mRNA splicing, as well as protein splicing factors. In this paper we show that all of the phosphorylated, mAb 104 detectable, Ser/Arg-rich essential splicing factors (SR proteins) in the nucleoplasm are integral components of the InRNP particles, whereas only part of the essential splicing factor U2AF65 (U2 snRNP auxiliary factor) and the polypyrimidine tract binding protein (PTB) are associated with these particles. This finding suggests a limiting role for SR proteins in the assembly of the InRNP particles. We further show that the structural integrity of InRNP particles is sensitive to variations in the phosphorylation levels of the SR proteins. |
| Databáze: | OpenAIRE |
| Externí odkaz: |
|