Genomic analyses of H1 cells induced by FOXO1. Genomic analyses of H1 cells induced by FOXO1

Insufficient understanding on cold adaptation technically restricts donor tissue banking. Here we identify FOXO1 as a conserved transcription factor for cell cold survival, relocating from cytosol to nucleus when temperature drops. FOXO1 small ubiquitin-like modifiers (SUMO) -interacting motif (SIM) antagonizes FOXO1-Importin-7 interaction regardless of temperature. At 37°C, SIM enhances FOXO1 interactions with SUMO E3 ligase RANBP2 and Exportin-1, FOXO1 hence cytoplasmic; at 4°C, FOXO1-Importin-7 interaction increases probably via RANBP2, making FOXO1 nuclear. These features enable fine-tuned FOXO1 regulations on chromatin folding and subsequent gene expression. Using these key factors as readouts, a ‘hibernation solution’ was developed, enabling long-term pancreatic islet cold storage and transplantation to cure diabetes. Henceforth, targeting FOXO1 SIM or the SUMO machinery may aid tissue/organ survival from long-term cold and other stresses. Overall design: Examination of FOXO1 binding in H1 cells, including two replicates in H1.