title: RNA binding regulates TRIM25-mediated RIG-I  ubiquitination
creator: Haubrich, Kevin
subject: ddc-500
subject: 500 Natural sciences and mathematics
subject: ddc-570
subject: 570 Life sciences
description: TRIM25 is an E3 ligase of the tripartite motif protein family, that is best known for its function in innate immunity, where it activates the pattern recognition receptor RIG-I. More recently, it was identified as a putative RNA binding protein, though lacking domains with known RNA-binding potential. In this thesis, I present evidence that RNA binding is mediated by the coiled-coil (CC) and PRY/SPRY domain with possible contributions of the disordered linker connecting the domains. Using NMR spectroscopy and mutational analysis, I could map the RNA binding site on these domains. Small-angle X-ray scattering indicates that RNA-binding stabilizes an inherent, but weak interaction between these domains leading to a more rigid domain architecture possibly explaining the increase in ubiquitination activity in the presence of RNA observed by us and others. In line with that, mutants affecting RNA binding or the weak CC:PRY/SPRY interaction also reduced ubiquitination of the RIG-I caspase-activation and recruitment domains (CARDs). RNA binding in addition promotes phase-separation and association with RIG-I, as our results indicate that there is no direct protein-protein interaction between TRIM25 and RIG-I. This reconciles seemingly controversial results in recent studies and contributes to further unravel the mechanism behind the immune response activation upon viral infection.
date: 2021
type: Dissertation
type: info:eu-repo/semantics/doctoralThesis
type: NonPeerReviewed
format: application/pdf
identifier: https://archiv.ub.uni-heidelberg.de/volltextserverhttps://archiv.ub.uni-heidelberg.de/volltextserver/28606/1/thesis_haubrich_2020_printed-A.pdf
identifier: DOI:10.11588/heidok.00028606
identifier: urn:nbn:de:bsz:16-heidok-286069
identifier:   Haubrich, Kevin  (2021) RNA binding regulates TRIM25-mediated RIG-I ubiquitination.  [Dissertation]     
relation: https://archiv.ub.uni-heidelberg.de/volltextserver/28606/
rights: info:eu-repo/semantics/openAccess
rights: Please see front page of the work (Sorry, Dublin Core plugin does not recognise license id)
language: eng