Amino acids 17-53 have been deleted.
When CycAα1-31,39-44.Scer\UAS is driven by Scer\GAL4prd.RG1 a slight delay in mitosis 16 is seen. An extra S phase is detected (by BrDU incorporation) followed by an extra M phase.
Scer\GAL4prd.RG1/CycAδ17-53.UAS partially rescues CycAunspecified
The addition of this mutant transgene to CycAunspecified mutants allows the progression into mitosis 16.