Palmitoyl-protein thioesterase, an enzyme implicated in neurodegeneration,is localized in neurons and is developmentally regulated in rat brain

Palmitoyl-protein thioesterase (PPT) is an enzyme involved in cleavage of p almitate residues from acylated proteins. Mutations in PPT gene cause a sev ere neurodegenerative disorder, infantile neuronal ceroid-lipofuscinosis (I NCL), characterized by loss of cortical neurons. In order to clarify the ro le of PPT and palmitoylation/depalmitoylation in the development of CNS and pathogenesis of infantile neuronal ceroid-lipofuscinosis (INCL), we studie d the localization and expression of PPT in developing rats. Using immunohi stochemical methods, we show for the fi rst time that PPT is truly localize d in neurons. Further, using RT-PCR and Western blotting, we show that expr ession of PPT in rat brain is developmentally regulated, with increasing ex pression during the maturation of CNS, reaching the maximum in young adulth ood. The presented data support the view of PPT being essential for both de velopment and maintenance of cortical neurons. (C) 1999 Elsevier Science Ir eland Ltd. All rights reserved.