The 3' end of the coding region is absent.
to1 flies feed more than control flies. This is because they feed at a greater frequency, rather than by increasing the volume of intake per proboscis extension.
Homozygotes show a significant reduction in courtship index. Males do not display male-chaining behaviour.
to1 flies exhibit defects in both circadian activity and survival in starvation conditions. In two days without food mutants show only two peaks of activity (compared to at least three in wild-type) and the average death time is 20 hours (instead of 30 hours in wild-type). however the mutants are more active during the activity decline that follows the first activity peak.
fru3, to1 has abnormal courtship behavior phenotype, suppressible by Tp(3;Y)A81
fru3, to1 has abnormal courtship behavior phenotype, suppressible by Tp(3;Y)L58
to1/to1 is an enhancer of abnormal courtship behavior phenotype of fru3
to1/to1 is an enhancer of abnormal courtship behavior phenotype of fru4
Expression of toScer\UAS.cLa, under the control of Scer\GAL4oeE in fru4/+, to1/to1 flies suppresses the mutant courtship phenotype.
The addition of to1/to1 to fru4/+ or fru3/+ leads to a significant reduction in courtship index. Although reduced courtship is not abolished, Mutant males are capable of all stages of courtship, but perform less frequently. This reduction is not caused by a reduction in general activity. The addition of the fru carrying Tp(3;Y)A81 or Tp(3;Y)L58 rescues this enhancement phenotype.
to1 is rescued by Scer\GAL4tim.PE/toUAS.cSBa