N-cadherinو ،NCAM و ،NCAM-L بررسى پروفايل بيانى ژن هاى 1در بن ياخته هاى عصبى مغز موش بالغ و سلول هاى Ninjurin- و 2 Ninjurin-1حاصل از القاى تمايز عصبى آنها

Gene Expression Profiling of NCAM, NCAM-L1, N-Cadher- in, Ninjurin-1 and Ninjurin-2 during the Course of Differentiation of Murine Neural Stem Cells

Objective: To evaluate and compare the gene expression profiles of Ninjurin-1 and Nin- jurin-2 with the expressions of L1 family of cell adhesion molecules (NCAM-L1), neural cell adhesion molecules (NCAM), and N-cadherin during the course of neural differentia­tion of mouse neural stem cells (NSCs). Materials and Methods: Briefly, for neural stem cell isolation, the frontal part of an adult mouse brain was minced in phosphate buffered saline (PBS) and digested by an en­zyme solution which contained hyaluronidase and trypsin. Isolated cells were cultured in medium supplemented by epidermal growth factor (EGF) and basic fibroblast growth factor (bFGF). After seven days, primary neurospheres appeared in culture medium. After transfer to poly-L-ornithine coated dishes that contained culture medium supplemented with 1% fetal bovine serum (FBS), the primary neurospheres differentiated into neural-like and neuroglial-like cells. Differentiated cells were examined by morphological, immunocy- tochemical, and molecular evaluations. Results: Our results showed that isolated cells from the preventricular area of mouse adult brain proliferated in medium which contained EGF and bFGF, and expansion of the cells continued until passage 14 without losing morphological and neurogenesis capac­ity. Multiple passaging confirmed the sternness nature of the isolated cells. The isolated NSCs were able to differentiate into neural-like and neuroglial-like cells after transfer to poly-L-ornithine coated dishes that contained culture medium supplemented with 1% FBS. Molecular studies for NCAM, NCAM-L1, and N-Cadherin genes, as well as im- munocytochemical analysis for NCAM-L1 and NCAM proved the differentiation. Our data also revealed, for the first time, gene expression profiling of Ninurin-1 and Ninjurin-2, two novel cell adhesion molecules (CAMs), during the course of differentiation of neural stem cells. Conclusion: The induction of neural differentiation in mouse NSCs initiates the expres­sion of NCAM-L1, NCAM, and N-cadherin which can be the proof of complete neural dif­ferentiation. In addition, our results indicate that the expression of Ninjurin-1 increases af­ter neural induction much like the expressions of NCAM-L1, NCAM, and N-cadherin. This data suggests the probable importance of Ninjurin-1 in both the morphology and function of neural cells. The data in this study also reveals that the expression of Ninjurin-2, in con­trast with Ninjurin-1, initiates and continues until the differentiation termination point. This suggests that although Ninjurin-1 and Ninjurin-2 share conserved hydrophobic regions for their transmembrane domains, their roles in nerve cells are probably different.