1. Interface-guided phenotyping of coding variants in the transcription factor RUNX1.
- Author
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Ozturk, Kivilcim, Panwala, Rebecca, Sheen, Jeanna, Ford, Kyle, Jayne, Nathan, Portell, Andrew, Zhang, Dong-Er, Hutter, Stephan, Haferlach, Torsten, Ideker, Trey, Mali, Prashant, and Carter, Hannah
- Subjects
CP: Genomics ,CP: Molecular biology ,Perturb-seq ,RNA-seq ,cancer ,coding variant ,interface ,protein-protein interaction ,single-cell ,transcription factor ,Humans ,Binding Sites ,Cell Line ,Tumor ,Core Binding Factor Alpha 2 Subunit ,Mutation ,Mutation ,Missense ,Phenotype ,Single-Cell Analysis - Abstract
Single-gene missense mutations remain challenging to interpret. Here, we deploy scalable functional screening by sequencing (SEUSS), a Perturb-seq method, to generate mutations at protein interfaces of RUNX1 and quantify their effect on activities of downstream cellular programs. We evaluate single-cell RNA profiles of 115 mutations in myelogenous leukemia cells and categorize them into three functionally distinct groups, wild-type (WT)-like, loss-of-function (LoF)-like, and hypomorphic, that we validate in orthogonal assays. LoF-like variants dominate the DNA-binding site and are recurrent in cancer; however, recurrence alone does not predict functional impact. Hypomorphic variants share characteristics with LoF-like but favor protein interactions, promoting gene expression indicative of nerve growth factor (NGF) response and cytokine recruitment of neutrophils. Accessible DNA near differentially expressed genes frequently contains RUNX1-binding motifs. Finally, we reclassify 16 variants of uncertain significance and train a classifier to predict 103 more. Our work demonstrates the potential of targeting protein interactions to better define the landscape of phenotypes reachable by missense mutations.
- Published
- 2024