Interactions between DSIF (DRB sensitivity inducing factor), NELF (negative elongation factor), and the Drosophila RNA polymerase II transcription elongation complex.

摘要: Negative elongation factor (NELF) and 5,6-dichloro-1-β-D-ribofuranosylbenzimidazole sensitivity-inducing (DSIF) are involved in pausing RNA Polymerase II (Pol II) the promoter-proximal region of hsp70 gene Drosophila, before heat shock induction. Such blocks widespread Drosophila genome. However, mechanism by which DSIF NELF participate setting up paused Pol remains unclear. We analyzed interactions among DSIF, NELF, a reconstituted complex to gain insight into pausing. Our results show that require nascent transcript longer than 18 nt stably associate with complex. Protein-RNA cross-linking reveals Spt5, largest subunit contacts as emerges from Taken together, these provide possible model binds via association subsequently recruits NELF. Although were both required for inhibition transcription, we did not detect NELF-RNA contact when was between 22 31 nt long, encompasses where occurs on many genes Drosophila. This raises possibility binding is necessary