During sub-confluent growth conditions, neither wild-type nor homozygous CbCln3Δex7/8 cells displayed autofluorescence or subunit c inclusion formation (data not shown). However, when cells were aged at confluency (3+ days post-confluency), homozygous CbCln3Δex7/8 cellular subunit c levels were elevated beyond normal wild-type levels by immunostaining (Fig. 4a) and immunoblot analysis (Fig. 4b). Autofluorescent signal sometimes overlapped with subunit c signal, but also was elevated more diffusely (Fig. 4a). Moreover, although multilamellar "fingerprint" profiles were not detected, confluency-aged homozygous CbCln3Δex7/8 cells displayed numerous ultrastructural abnormalities including electron dense inclusions characteristic of lipofuscin and large autophagosomes that contained dense core structures, degenerating mitochondria, and many smaller vesicles (Fig. 4c). Inclusion bodies and autophagosomes were infrequently observed in confluency-aged wild-type cultures (data not shown).