SEC23IP (SEC23 interacting protein) is a regulatory protein localized at ER exit sites (ERES) that plays a central role in endoplasmic reticulum-to-Golgi transport. SEC23IP contains a conserved SAM-DDHD domain module that recognizes phosphatidylinositol phosphates (PI3P, PI4P, PI5P) and phosphatidic acid, using lipid signals to control COPII coat assembly and spatial organization at ERES 1. Functionally, SEC23IP recruits the lipid transfer protein VPS13B/COH1 to ERES-Golgi interfaces, promoting tubular ERGIC formation and facilitating ER export of cargo including procollagen 2. SEC23IP knockout impairs this trafficking pathway, suggesting relevance to Cohen syndrome pathogenesis. Clinically, SEC23IP has been implicated in multiple disorders. Homozygous truncating variants in SEC23IP were identified in consanguineous families with neurodevelopmental disorders 3, while rare coding variants at the SEC23IP locus showed significant association with adult ADHD 4. In neurodegenerative diseases, SEC23IP emerged as a candidate therapeutic target for Parkinson's disease through integrative genetic and proteomic analysis 5, though large-scale exome sequencing found no statistically significant rare variant enrichment 6. Additionally, SEC23IP gene fusions have been detected in myxoinflammatory fibroblastic sarcoma 7. These findings indicate SEC23IP functions as a key ERES organizer with implications for both developmental and neurodegenerative disease pathogenesis.