Component of the SPOTS complex that acts as a negative regulator of sphingolipid synthesis. Acts by inhibiting serine palmitoyltransferases (LCB1 and LCB2) activity. Component of the SPOTS complex, at least composed of LCB1/2 (LCB1 and/or LCB2), ORM1/2 (ORM1 and/or ORM2), SAC1 and TSC3. Phosphorylated in case of disruption of sphingolipid synthesis. Phosphorylation regulates inhibitory activity of serine palmitoyltransferases (LCB1 and LCB2). Present with 2800 molecules/cell in log phase SD medium. Belongs to the ORM family.