Dynamics of Fanconi anemia protein D2 in association with nuclear lipid droplet formation

Abstract

Fanconi anemia (FA) is a rare genetic disease caused by the loss of function of one of the 22 associated genes and is characterized by bone marrow failure, cancer predisposition, and developmental defects. The proteins encoded by these genes (FA proteins) mainly function in DNA damage response and repair. Although FA deficiency has multiple effects on the regulation of lipid metabolism, the molecular function of FA proteins in the context of FA pathology remains unclear. In the present study, we demonstrated that FANCD2, a key component of FA proteins, interacts with lipid metabolism-related factors and that FANCD2 deficiency downregulates the cellular levels of fatty acids. Moreover, a portion of FANCD2 is localized to nuclear lipid droplets in response to oleic acid treatment. These subcellular dynamics are independent of FANCD2 monoubiquitination, which is essential for the DNA damage response. Collectively, these findings demonstrate that FANCD2 responds to not only DNA damage but also oleic acid exposure, providing insights into the pathogenesis of lipid dysregulation in FA.