transheterozygous adults display significantly reduced adult lifespan and aged adults display more severe neurodegenerative phenotype (compromised tissue integrity particularly in the mushroom body) relative to control flies of comparable physiological age (= at equivalent stage of population mortality) but this effect is not due to either increased apoptosis or necrosis. The aged mutant adults however accumulate more autophagosomal organelles relative to controls. Cdk5α20C
adult also display significantly reduced survival rate upon starvation.
MARCM clones in the adult mushroom body initially display very low frequency of morphological abnormalities compared to controls but in aged flies show gross swelling of the proximal region of the axon in all three classes of adult Kenyon cells.
Approximately 50% of Cdk5α20C
mutant embryos lacking both maternal and zygotic Cdk5α
exhibit motor nerve axonal aberrations and guidance errors at modest expressivity. These defects include overextended intersegmental nerves, missing dorsal "a" branch of segmental nerves without the lateral branch being affected, missing "b" branch of intersegmental nerves and stalled transverse nerves. Adult Cdk5α20C
mutants exhibit progressive loss of motor coordination.
The lifespan of Cdk5α20C
flies is reduced by about one third relative to controls.