dCas9-effector NPCs per well (3.5 × 105) were seeded onto growth factor-reduced Matrigel-coated 24-well plates in NPC medium containing 1 μg/mL puromycin. The next day, lentiviruses generated as above were added and cultures were spinfected (1 hr, 1,000 × g, 25°C). Following spinfection, plates were transferred to a cell culture incubator for 3 hr. The medium was then removed and replaced with fresh NPC medium containing 1 μg/mL puromycin. Cells were harvested 48 hr later.
