A Critical Re-evaluation of "Adipogenin Promotes the Development of Lipid Droplets by Binding A Dodecameric Seipin Complex" by Li et al., Science 2025;390(6773):eadr9755; DOI: 10.1126/science.adr9755

This work provides a comprehensive, evidence-based critical analysis of the 2025 Science article by Li et al., titled “Adipogenin promotes the development of lipid droplets by binding a dodecameric seipin complex.” The original study proposes that the adipose microprotein adipogenin (Adig) directly binds and stabilizes a dodecameric Seipin oligomer to promote lipid droplet (LD) biogenesis. Because this claim, if validated, would represent a major mechanistic advance in cellular lipid storage biology, a rigorous reassessment of the structural, biochemical, cellular, and physiological evidence is scientifically essential.

In this commentary, we conducted an exhaustive, figure-by-figure evaluation of all main-text figures, Extended Data figures, and Supplementary figures presented by Li et al. The analysis reveals that many central claims of the paper remain inadequately supported by the data. Major concerns include: (1) lack of definitive cryo-EM validation for the proposed dodecameric Seipin architecture; (2) insufficient evidence for direct and specific Adig–Seipin binding; (3) methodological limitations in biochemical interaction assays; (4) incomplete control for cellular differentiation, metabolic state, and lipid synthesis pathways; and (5) absence of systemic metabolic characterization in the in vivo experiments. Critically, several key interpretations appear to rely on overexpression artifacts, symmetry-imposed structural averaging, or underdetermined density assignments.

This commentary does not dispute that Adig may influence LD biology, nor does it argue against the possibility of an Adig–Seipin interaction. Rather, it emphasizes that the mechanistic conclusions drawn by Li et al. substantially exceed what their data can currently justify. By integrating structural biology principles, lipid-droplet physiology, microprotein biochemistry, and metabolic systems biology, this critique identifies the specific experimental gaps that must be addressed for the proposed model to be validated.

The work concludes with detailed recommendations for essential follow-up studies, including symmetry-free cryo-EM reconstructions, biophysical affinity measurements, binding-deficient mutant analyses, comprehensive lipidomics, differentiation-matched LD assays, and in vivo metabolic phenotyping. These refinements will be necessary for accurate mechanistic characterization of Adig function and for establishing whether the Adig–Seipin axis constitutes a physiologically dominant pathway in adipose lipid storage.