F to A mutation is in the RNP2 motif of the RRM1 (RNA recognition motif 1) domain.
lark1 homozygotes carrying larkRRM1.RNP2.T:Ivir\HA1 show normal eclosion rhythms in 12 hour light:12 hour darkness conditions and normal free-running eclosion rhythms.
larkRRM1.RNP2.Tag:HA rescues lark1