Fig. 3.

Light triggers anagen entry through melanopsin and the ipRGC-to-SCN projection. (A) Effect of Opn4 deletion. Light-induced anagen entry was completely abolished in Opn4^−/− mice. *P < 0.05 (n = 10). (B) Effect of depleting Brn3b⁺ ipRGCs. Anagen could still be induced in Opn4^Cre/+; Brn3b^Z-dta/+ mice, but light-induced anagen entry was slightly delayed and reduced in Opn4^Cre/+; Brn3b^Z-dta/+ mice compared with wild-type mice. *P < 0.05 (n = 10). (C) Effect of reduced neuronal input from ipRGCs. Reduced ipRGC numbers in Opn4^dta/+ mice delayed and reduced light-induced anagen entry. *P < 0.05 (n = 5).