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A loss-of-function of polyglutamine tract-binding protein 1 (PQBP1) induced by frameshift mutations is believed to cause X-linked mental retardation. However, the mechanism by which structural changes in PQBP1 lead to mental retardation is unknown. Here we present the crystal structure of a C-terminal fragment of PQBP1 in complex with the spliceosomal protein U5-15kD. The U5-15kD hydrophobic groove recognizes a YxxPxxVL motif in PQBP1, and mutations within this motif cause a loss-of-function phenotype of PQBP1 in vitro. The YxxPxxVL motif is absent in all PQBP1 frameshift mutants seen in cases of mental retardation. These results suggest a mechanism by which the loss of the YxxPxxVL motif could lead to the functional defects seen in this type of mental retardation.
Mutations in the PQBP1 gene prevent its interaction with the spliceosomal protein U5-15kD.,Mizuguchi M, Obita T, Serita T, Kojima R, Nabeshima Y, Okazawa H Nat Commun. 2014 Apr 30;5:3822. doi: 10.1038/ncomms4822. PMID:24781215[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
↑ Mizuguchi M, Obita T, Serita T, Kojima R, Nabeshima Y, Okazawa H. Mutations in the PQBP1 gene prevent its interaction with the spliceosomal protein U5-15kD. Nat Commun. 2014 Apr 30;5:3822. doi: 10.1038/ncomms4822. PMID:24781215 doi:http://dx.doi.org/10.1038/ncomms4822
