4PJ3

Structural insight into the function and evolution of the spliceosomal helicase Aquarius, Structure of Aquarius in complex with AMPPNP

Summary for 4PJ3

• Entry DOI: 10.2210/pdb4pj3/pdb
• Related: 4PJ4
• Descriptor: Intron-binding protein aquarius, PHOSPHOAMINOPHOSPHONIC ACID-ADENYLATE ESTER, MAGNESIUM ION, ... (4 entities in total)
• Functional Keywords: rna helicase, pre-mrna splicing, rna binding protein
• Biological source: Homo sapiens (Human)
• Cellular location: Nucleus : O60306
• Total number of polymer chains: 1
• Total formula weight: 173110.18

Authors

De, I.,Bessonov, S.,Hofele, R.,dos Santos, K.F.,Will, C.L.,Urlaub, H.,Luhrmann, R.,Pena, V. (deposition date: 2014-05-11, release date: 2015-01-21, Last modification date: 2024-10-09)

Primary citation

De, I.,Bessonov, S.,Hofele, R.,Dos Santos, K.,Will, C.L.,Urlaub, H.,Luhrmann, R.,Pena, V.
The RNA helicase Aquarius exhibits structural adaptations mediating its recruitment to spliceosomes.
Nat.Struct.Mol.Biol., 22:138-144, 2015

PubMed Abstract: Aquarius is a multifunctional putative RNA helicase that binds precursor-mRNA introns at a defined position. Here we report the crystal structure of human Aquarius, revealing a central RNA helicase core and several unique accessory domains, including an ARM-repeat domain. We show that Aquarius is integrated into spliceosomes as part of a pentameric intron-binding complex (IBC) that, together with the ARM domain, cross-links to U2 snRNP proteins within activated spliceosomes; this suggests that the latter aid in positioning Aquarius on the intron. Aquarius's ARM domain is essential for IBC formation, thus indicating that it has a key protein-protein-scaffolding role. Finally, we provide evidence that Aquarius is required for efficient precursor-mRNA splicing in vitro. Our findings highlight the remarkable structural adaptations of a helicase to achieve position-specific recruitment to a ribonucleoprotein complex and reveal a new building block of the human spliceosome.

PubMed: 25599396
DOI: 10.1038/nsmb.2951

Experimental method

X-RAY DIFFRACTION (2.3 Å)