Integral ER membrane protein, regulates phospholipid metabolism; one of 6 proteins (Ist2p, Scs2p, Scs22p, Tcb1p, Tcb2p, Tcb3p) that connect the ER to the plasma membrane (PM); regulates PI4P levels by controlling access of Sac1p to PM substrate PI4P; interacts with FFAT motifs in Opi1p, Swh1p, Osh2p and Osh3p; role in NVJ integrity and micronucleophagy; role in telomeric silencing; VAMP-associated protein (VAP) homolog; SCS2 has a paralog, SCS22, that arose from the whole genome duplication