eprintid: 28606
rev_number: 19
eprint_status: archive
userid: 5264
dir: disk0/00/02/86/06
datestamp: 2020-07-17 09:52:12
lastmod: 2021-06-17 10:46:49
status_changed: 2020-07-17 09:52:12
type: doctoralThesis
metadata_visibility: show
creators_name: Haubrich, Kevin
title: RNA binding regulates TRIM25-mediated RIG-I
ubiquitination
subjects: ddc-500
subjects: ddc-570
divisions: i-140001
divisions: i-850800
adv_faculty: af-14
keywords: TRIM25, RIG-I, RNA binding proteins, E3 ligases, innate immunity
abstract: 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
id_scheme: DOI
id_number: 10.11588/heidok.00028606
ppn_swb: 1760722200
own_urn: urn:nbn:de:bsz:16-heidok-286069
date_accepted: 2020-06-15
advisor: HASH(0x561a628d3790)
language: eng
bibsort: HAUBRICHKERNABINDING2021
full_text_status: public
place_of_pub: Heidelberg
citation:   Haubrich, Kevin  (2021) RNA binding regulates TRIM25-mediated RIG-I ubiquitination.  [Dissertation]     
document_url: https://archiv.ub.uni-heidelberg.de/volltextserver/28606/1/thesis_haubrich_2020_printed-A.pdf