RFX1 and infection: By contrast, we found that ATOH1 gene infection alone or in combination with RFX1/RFX3 at the OP stage could significantly increase the number of MYO7AmCherry-positive cells on day 28, implying that the decline of ATOH1 mRNA expression from the OP to HC stage (Fig. 1b) could be compensated by the infection of lenti-ATOH1 at the OP stage (Fig. 4b).