Project description:Isolated complex I (CI) deficiencies are a major cause of primary mitochondrial disease. A substantial proportion of CI deficiencies are believed to arise from defects in CI assembly factors (CIAFs) that are not part of the CI holoenzyme. The biochemistry of these CIAFs is poorly defined, making their role in CI assembly unclear, and confounding interpretation of potential disease-causing genetic variants. To address these challenges, we devised a deep mutational scanning approach to systematically assess the function of thousands of NDUFAF6 genetic variants. Guided by these data, biochemical analyses and cross-linking mass spectrometry, we discovered that the CIAF NDUFAF6 facilitates incorporation of NDUFS8 into CI and reveal that NDUFS8 overexpression rectifies NDUFAF6 deficiency. Our data further provide experimental support of pathogenicity for seven novel NDUFAF6 variants associated with human pathology and introduce functional evidence for over 5,000 additional variants. Overall, our work defines the molecular function of NDUFAF6 and provides a clinical resource for aiding diagnosis of NDUFAF6-related diseases.
Project description:Cross-linking/mass spectrometry was used to study inter-domain interactions in the multifunctional AROM complex from Chaetomium thermophilum.
Project description:UV cross-linking and immunoprecipitation (CLIP) and individual-nucleotide resolution CLIP (iCLIP) are the most frequently used methods to study protein-RNA interactions in the intact cells and tissues, but their relative advantages or inherent biases have not been evaluated. To benchmark CLIP and iCLIP method, we performed iCLIP with Nova protein, which is the most extensively studied protein by CLIP. Further, we assessed UV-C-induced cross-linking preferences, by exploiting the UV-independent formation of covalent RNA cross-links of the mutant RNA methylase NSUN2.
Project description:To capture protein interactions, cross-linking experiments were performed on immune complexes prepared by affinity-purification of DMXL1-mNG from U2OS cells.
Project description:Chemical cross-linking coupled to mass spectrometry using the amine-reactive DSS reagent was used to study the interactions between the RNA helicase Prp43 and its interactors, Pxr1 and Tma23, in Saccharomyces cerevisiae.
Project description:This study aims to study binding events between the Zika virus RNA genome and endogenous transcripts during infection of a human cell line. We develop a novel psolaren-based cross-linking technique to preserve interactions between mRNA and the Zika genome. Interacting RNA molecules are ligated together prior to reversal of the cross-links and selection for Zika-containing fragments. Reverse transcription and paired-end high-throughput sequencing then allow us to identify the interacting transcripts. We generated three batches of libraries, where all samples in each batch were generated from the same pool of RNA. Within each batch, we have the livefire sample, where the protocol was performed as described above; a reverse-control sample, where the protocol was performed by reversing the cross-links prior to ligation; and a no-cross-link control, where the protocol was performed without any cross-linking. The latter two samples represent negative controls where no genuine interactions should be observed.
Project description:Structural study of the polyA signal recognition by the human CPSF using X-ray crystallography, cross-linking MS, pull-downs and fluorescence polarisation assays.