Choroidal melanocytes - a model for studying the aging process in nonreplicative differentiated cells.
Choroidal melanocytes differentiate and cease to divide early in postnatal life. They have characteristic organelles, the melanosomes, which are formed from tyrosine in a reaction catalyzed by tyrosinase. As animals become old, enzyme activity declines and the melanosomes show changes that are quantitatively and qualitatively correlated to the animal's increasing age.
D000375:Aging; D000818:Animals; D002829:Choroid / Q000166:cytology* / Q000648:ultrastructure; D000882:Haplorhini; D008062:Lipofuscin / Q000032:analysis; D008253:Macaca mulatta; D008544:Melanocytes / Q000648:ultrastructure*; D008856:Microscopy, Fluorescence; D010857:Pigment Epithelium of Eye / Q000648:ultrastructure
D008062:Lipofuscin