Alkaline Ceramidase 2 (ACER2)

Alkaline ceramidase 2 (ACER2), a Golgi enzyme, regulates β1 maturation by controlling the generation of sphingosine. ACER2 overexpression inhibited β1 maturation, thus leading to a decrease in the levels of mature β1 in T-REx HeLa cells, whereas RNA interference-mediated knockdown of ACER2 enhanced β1 maturation in MCF-7 cells. ACER2 overexpression decreased the cell surface levels of β1 integrins, thus inhibiting cell adhesion to fibronectin or collagen, whereas ACER2 knockdown has the opposite effects. Treatment with all-trans retinoic acid (ATRA) increased both the expression of ACER2 and the generation of sphingosine in HeLa cells and inhibited β1 maturation. ACER2 overexpression inhibited the stimulatory effects of PMA on both β1 maturation and cell adhesion.