Structural and biochemical analyses reveal that the conserved Nop domain in hPrp31 maintains high ribonucleoprotein binding selectivity despite relaxed RNA sequence requirements.
The study elucidates the structural basis for hPrp31 binding selectivity to U4 snRNP and provides a potential molecular mechanism for retinitis pigmentosa.
Although highly homologous, the spliceosomal hPrp31 and the nucleolar Nop56 and Nop58 (Nop56/58) proteins recognize different ribonucleoprotein (RNP) particles. hPrp31 interacts with complexes containing the 15.5K protein and U4 or U4atac small nuclear RNA (snRNA), whereas Nop56/58 associate with 15.5K-box C/D small nucleolar RNA complexes. We present structural and biochemical analyses of hPrp31-15.5K-U4 snRNA complexes that show how the conserved Nop domain in hPrp31 maintains high RNP binding selectivity despite relaxed RNA sequence requirements. The Nop domain is a genuine RNP binding module, exhibiting RNA and protein binding surfaces. Yeast two-hybrid analyses suggest a link between retinitis pigmentosa and an aberrant hPrp31-hPrp6 interaction that blocks U4/U6-U5 tri-snRNP formation.
Liu et al. (Thu,) reported a other. Structural and biochemical analyses reveal that the conserved Nop domain in hPrp31 maintains high ribonucleoprotein binding selectivity despite relaxed RNA sequence requirements.