Flotillin 1 (FLOT1)

Flot1 encodes a deduced 428-amino acid protein with a predicted molecular mass of 47 kD. It contains 2 hydrophobic domains and several potential phosphorylation sites. Flot1 shares 47% amino acid identity with both mouse and human FLOT2. Northern blot analysis of mouse tissues revealed expression in adipose tissue, heart, skeletal muscle, and lung. By Western blot analysis, Flot1 was also found as a 47-kD protein in caveolin-rich membrane domains isolated from human lung and from cultured mouse adipocytes. Flotillin-1 colocalized with PTOV1 at the plasma membrane and in the nucleus, and it entered the nucleus concomitant with PTOV1 shortly before initiation of S phase. Protein levels of PTOV1 and flotillin-1 oscillated during the cell cycle, with a peak in S phase.