Integrative Chemical Genetics Platform Identifies Condensate Modulators Linked to Neurological Disorders

Aberrant biomolecular condensates are implicated in multiple incurable neurological disorders, including Amyotrophic Lateral Sclerosis, Frontotemporal Dementia, and DYT1 dystonia. However, the role of condensates in driving disease etiology remains incompletely understood. Here, we establish myeloid leukemia factor 2 (MLF2) as a disease-agnostic biomarker of phase transitions. Using MLF2 as a high-content screening readout enables the identification of condensate modulators across both chemical and genetic perturbations. We uncover FDA-approved drugs that potently modulate condensates, validating our pipeline for facile drug discovery. Leveraging our methodology for a genome-wide CRISPR/Cas9 screen reveals genes linked to primary microcephaly and related neurodevelopmental disorders that result in proteotoxic condensates. Machine learning establishes two phenotypic clusters, with RNF26 deletion provoking nuclear envelope condensates reminiscent of nuclear pore defects, while loss of ZNF335, a known microcephaly-causative gene, drives accumulation of distinct nucleoplasmic condensates. Our study establishes a link between aberrant phase transitions and microcephaly, highlighting corrective chemical modulators.