D-Aspartate is present in human retinoblastoma Y79 cells

In mammals, D-aspartate is present in various neuroendocrine cells, being especially abundant in pinealocytes. Although D-aspartate is suggested to be involved in some neuroendocrine function, little is known about its origins as well as its physiological roles. In the present study, we found that an appreciable amount of D-aspartate (50.8 pmol/1 x 10⁶ cells) is present in clonal human retinoblastoma Y79 cells. The amount of D-aspartate corresponds to 28% of that in rat pinealocytes. The D-aspartate concentration did not change with the culture duration or passage, suggesting de novo biosynthesis of it. Thus, Y79 cells may constitute a suitable experimental system for studies on the biogenesis and signal transduction of D-aspartate in mammalian cells.