Expression of Niemann-Pick type C transcript in rodent cerebellum in vivo and in vitro

This study assesses the developmental expression of the Niemann-Pick; type C mRNA in vivo and in vitro in rat cerebellum. NPC is an autosomal recessiv e neurovisceral lipid storage disease associated with an alteration in chol esterol trafficking. In the mouse model of NPC and in the early onset form of human NPC, Purkinje neurons are among the first neurological targets, su ffering stunted growth during postnatal development and dying, leading to a taxia, Recently, the genes responsible for human (NPC1) and mouse (Npc1) NP C disease have been cloned. Based on a highly homologous domain, we designe d primers to look for levels of Npc1 mRNA with a semi-quantitative reverse transcription-polymerase chain reaction (RT-PCR) approach using cyclophilin as an internal standard. Total RNA was isolated from various postnatal dev elopmental stages of the rat cerebellum as template for the analyses, Npc1 transcripts were observed at postnatal day 0 and at later stages of develop ment, both in vivo and in vitro from primary cerebellar cultures. To identi fy the location of Npc1 inside the cerebellum, we performed immunostaining with an anti-Npc1 antibody in primary rat cerebellar cultures identifying r eactive Purkinje neurons by double-labeling with the Purkinje specific mark er calbindin and sub-populations of glial cells. In summary, Npc1 is expres sed in rat cerebellum in vivo and in vitro and is expressed during early po stnatal development as well as in the adult cerebellum. Since Npc1 is expre ssed at similar levels throughout development, the vulnerability of Purkinj e neurons to this disease is likely to involve disruption of an interaction with other developmentally-regulated proteins. (C) 1999 Elsevier Science B .V. All rights reserved.