3t5x
PCID2:DSS1 StructurePCID2:DSS1 Structure
Structural highlights
Function[PCID2_HUMAN] Required for B-cell survival through the regulation of the expression of cell-cycle checkpoint MAD2L1 protein during B cell differentiation (By similarity). Component of the TREX-2 complex (transcription and export complex 2), composed of at least ENY2, GANP, PCID2, DSS1, and either centrin CETN2 or CETN3 (PubMed:22307388). The TREX-2 complex functions in docking export-competent ribonucleoprotein particles (mRNPs) to the nuclear entrance of the nuclear pore complex (nuclear basket). TREX-2 participates in mRNA export and accurate chromatin positioning in the nucleus by tethering genes to the nuclear periphery. Binds and stabilizes BRCA2 and is thus involved in the control of R-loop-associated DNA damage and transcription-associated genomic instability. R-loop accumulation does not increase in PCID2-depleted cells.[1] [2] [DSS1_HUMAN] Subunit of the 26S proteasome which plays a role in ubiquitin-dependent proteolysis.[3] Publication Abstract from PubMedThe conserved TREX-2 transcription-export complex integrates transcription and processing of many actively transcribed nascent mRNAs with the recruitment of export factors at nuclear pores and also contributes to transcriptional memory and genomic stability. We report the crystal structure of the Sac3-Thp1-Sem1 segment of Saccharomyces cerevisiae TREX-2 that interfaces with the gene expression machinery. Sac3-Thp1-Sem1 forms a previously uncharacterized PCI-domain complex characterized by the juxtaposition of Sac3 and Thp1 winged helix domains, forming a platform that mediates nucleic acid binding. Our structure-guided mutations support the idea that the Thp1-Sac3 interaction is an essential requirement for mRNA binding and for the coupling of transcription and processing to mRNP assembly and export. These results provide insight into how newly synthesized transcripts are efficiently transferred from TREX-2 to the principal mRNA export factor, and they reveal how Sem1 stabilizes PCI domain-containing proteins and promotes complex assembly. Structural basis for the assembly and nucleic acid binding of the TREX-2 transcription-export complex.,Ellisdon AM, Dimitrova L, Hurt E, Stewart M Nat Struct Mol Biol. 2012 Feb 19;19(3):328-36. doi: 10.1038/nsmb.2235. PMID:22343721[4] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. See AlsoReferences
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