5xyv
From Proteopedia
Crystal structure of drosophila melanogaster Rhino chromoshadow domain in complex with Deadlock N-terminal domain
Structural highlights
Function[DEL_DROME] Developmental protein involved in oogenesis (PubMed:16616913). Required for germline maintenance, stability of mitotic spindles, localization of patterning determinants, oocyte growth and fusome biogenesis in males and females (PubMed:16616913). Also required for dorso-ventral and antero-posterior patterning of oocyte and eggshell (PubMed:16616913). May be involved in microtubule function during oogenesis (PubMed:16616913). Part of a rhi-dependent transcription machinery that enables the generation of piRNA precursors from heterochromatin while maintaining the suppression of transposon-encoded promoters and enhancers (PubMed:28847004). Component of the RDC complex (rhi, del and cuff) which binds to repressive H3K9me3 marks in the piRNA clusters (PubMed:28847004). RDC promotes the bidirectional transcription of piRNA clusters at these sites by interacting with Moonshiner which forms a complex with the transcription initiation factors TfIIA-S and Trf2 (PubMed:28847004). This mechanism allows transcription to occur in piRNA clusters despite the lack of proper promoter elements and in the presence of the repressive H3K9me3 mark (PubMed:28847004).[1] [2] Publication Abstract from PubMedPIWI-interacting RNAs (piRNAs) silence transposons in germ cells to maintain genome stability and animal fertility. Rhino, a rapidly evolving heterochromatin protein 1 (HP1) family protein, binds Deadlock in a species-specific manner and so defines the piRNA-producing loci in the Drosophila genome. Here, we determine the crystal structures of Rhino-Deadlock complex in Drosophila melanogaster and simulans In both species, one Rhino binds the N-terminal helix-hairpin-helix motif of one Deadlock protein through a novel interface formed by the beta-sheet in the Rhino chromoshadow domain. Disrupting the interface leads to infertility and transposon hyperactivation in flies. Our structural and functional experiments indicate that electrostatic repulsion at the interaction interface causes cross-species incompatibility between the sibling species. By determining the molecular architecture of this piRNA-producing machinery, we discover a novel HP1-partner interacting mode that is crucial to piRNA biogenesis and transposon silencing. We thus explain the cross-species incompatibility of two sibling species at the molecular level. Structural insights into Rhino-Deadlock complex for germline piRNA cluster specification.,Yu B, Lin YA, Parhad SS, Jin Z, Ma J, Theurkauf WE, Zhang ZZ, Huang Y EMBO Rep. 2018 Jun 1. pii: embr.201745418. doi: 10.15252/embr.201745418. PMID:29858487[3] From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine. References
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Categories: Drome | Huang, Y | Yu, B W | Chromoshadow | Complex | Pirna pathway | Protein binding
