4PJO

Minimal U1 snRNP

Summary for 4PJO

• Entry DOI: 10.2210/pdb4pjo/pdb
• Related: 2Y9A 3CW1
• Descriptor: Small nuclear ribonucleoprotein Sm D3, U1 RNA variant (48-MER) with 4-helix junction replaced by kissing loop (HIV-1 (Mal) DIS) and shorter stem-loop 4., RNA (5'-R(*AP*GP*GP*UP*AP*AP*GP*UP*CP*C)-3'), ... (19 entities in total)
• Functional Keywords: u1 snrnp, spliceosome, pre-mrna splicing, ribonucleoprotein, splicing
• Biological source: Homo sapiens (Human); More
• Cellular location: Cytoplasm, cytosol : P62318 P14678 P62314 P62316 P62304 P62306 P62308; Nucleus: P08621 P09234
• Total number of polymer chains: 44
• Total formula weight: 453815.90

Authors

Kondo, Y.,Oubridge, C.,van Roon, A.M.,Nagai, K. (deposition date: 2014-05-12, release date: 2014-12-31, Last modification date: 2023-12-20)

Primary citation

Kondo, Y.,Oubridge, C.,van Roon, A.M.,Nagai, K.
Crystal structure of human U1 snRNP, a small nuclear ribonucleoprotein particle, reveals the mechanism of 5' splice site recognition.
Elife, 4:-, 2015

PubMed Abstract: U1 snRNP binds to the 5' exon-intron junction of pre-mRNA and thus plays a crucial role at an early stage of pre-mRNA splicing. We present two crystal structures of engineered U1 sub-structures, which together reveal at atomic resolution an almost complete network of protein-protein and RNA-protein interactions within U1 snRNP, and show how the 5' splice site of pre-mRNA is recognised by U1 snRNP. The zinc-finger of U1-C interacts with the duplex between pre-mRNA and the 5'-end of U1 snRNA. The binding of the RNA duplex is stabilized by hydrogen bonds and electrostatic interactions between U1-C and the RNA backbone around the splice junction but U1-C makes no base-specific contacts with pre-mRNA. The structure, together with RNA binding assays, shows that the selection of 5'-splice site nucleotides by U1 snRNP is achieved predominantly through basepairing with U1 snRNA whilst U1-C fine-tunes relative affinities of mismatched 5'-splice sites.

PubMed: 25555158
DOI: 10.7554/eLife.04986

Experimental method

X-RAY DIFFRACTION (3.3 Å)