Budget Amount *help |
¥3,700,000 (Direct Cost: ¥3,700,000)
Fiscal Year 2000: ¥1,200,000 (Direct Cost: ¥1,200,000)
Fiscal Year 1999: ¥2,500,000 (Direct Cost: ¥2,500,000)
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Research Abstract |
Neural crest is a vertebrate specific population of cells. The crest cells arise at the dorsal aspect of the developing neural tube, migrate broadly in ther embryo, and subsequently give rise to neurons and gliain the peripheral nervous system, melanocyte in the skin, and mesenchymal tissues in the head. The recipent investigator have isolated cDNA that is expressed specifically in neural crest-derived Schwann cell precursors. This cDNA disgnated as millipede, encodes a novel secreted molecule possessing five times of EGF-like motif. The expression of millipede gene was found very early, but transiently in Schwann precursors in the develping peripheral nerve. In this study, Line investigator has isolated a cDNA of Schwann cell marker, PO, and compared the expression of PO and millipede. Millipede expression in the Schwann cell precursors was found to preceeded that of PO, and when PO expression became up-regulted, millipede expression diminished. This observation suggested that the early stage of Schwann cell development can be subdivided by the expression of these genes. To identify the target tissue and cells of millipede, the investigator constructed an expression vector of millipede-alkaline phosphatase fusion protein. Such vector was transfected into COS7 cell, and a conditioned medium was prepared. Staining of sections and primary cultures with this fusion protein revealed that millipede binds to neural crest cells and spinal nerve, These obsevation suggested that millipede functions as a autocrine and paracrine fuctor. Consdtioned medium prepared from millipede-transfected COS7 cells dramatically increased the proportion of PO positive cells in primary culture of neural crest cells, sggesting that milliepde regulates Schwann cell differentiation, growth and/or survival.
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