POSTER NO: 194

NSPL1, a member belonging to RTN family associated with the differentiation of brain tumor

Xiaowei Huang, Jin Liu, Yan Zhou, Hongbo Yang, Boqin Qiang, Jiangang Yuan
Institute of Basic Medical Science, Chinese Academy of Medical Sciences and Peking Union Medical College, National Laboratory of Medical Molecular Biology, National center of Human Genome Research, Dong Dan 3 Tiao 5 Hao, Beijing, 100005

NSPL1 cDNA with full length of 2559bp was the clone identified by our lab, and the protein it encoded belonged to RTN family, which had been localized on the membrane of endoplasmic reticulum. Northern blot hybridization under high stringency conditions revealed that NSPL1 gene had three different transcripts, with the length of 2.3kb, 2.6kb, 4kb respectively. The expression level of NSPL1 gene in brain was significantly higher than that in heart, placenta, kidney, skeletal muscle, lung, liver and pancreas. In situ hybridization using a digoxygenin labeled mouse homologue RNA probe to central nervous system (CNS) of mouse showed non-glia distribution, such as hippocampus, sub-thalamus nucleus, putamen and many other neuro-nucleus. After immune to the rabbit with the protein purified, we got the polyclonal antibody to the protein of NSPL1. In western blot, an obvious band was detected in the lane from mouse brain; in the other tissues such as heart, lung, liver, kidney, pancreas and skeletal muscle, no obvious signals could be detected. Moreover the immunohistochemistry showed that the distribution of NSPL1 protein was consistent with NSPL1 mRNA. NSPL1 protein was detected in the neurons of the ponds and cortex of cerebrum, nucleus of hippocampus and sub-thalamus, but also some fibrous structures in periamygdaloid cortex. Additionally, in situ hybridization and immunohistochemistry to the specimens of the patients with glioma showed that NSPL1 expressed in glioma whereas it expressed in non-glia cells in normal. In order to confirm the relationship between NSPL1 and the differentiation, we induced the neuroblastoma cell line SH-SY5Y with RA and extracted the RNA at the different time. The result of Northern blot revealed that NSPL1 was down-regulated during the cell differentiation. From these results, it was reasonable to assume that NSPL1 gene may associate with the differentiation of brain tumor.