Deletion of sequences from P{per13.2.HA10His} that encode amino acids 755 to 809 of per, a region that contains the major in vivo binding domain for the dco product.
Adult per01 flies expressing perΔ.T:Ivir\HA1,T:Zzzz\His6 (rescue flies) display robust circadian activity rhythm in constant dark (preceded by an 12:12 light:dark entrainment period) with a period of about 24 hr, similarly to wild-type.
perΔ.T:Ivir\HA1,T:Zzzz\His6 flies show a significant increase in arrhythmicity above controls. For those flies displaying rhythmic activity, the amplitudes of the rhythm are strongly reduced and the periods lengthened by 3-4 hours compared to controls.
perΔ.Tag:HA,Tag:polyHis fails to rescue per01
perΔ.T:Ivir\HA1,T:Zzzz\His6, per01 flies are arrhythmic.