Down syndrome （DS） is the most common cause of cognitive impairment associated with a congenital chromosomal abnormality, trisomy of chromosome 21. Mental retardation and congenital heart defects are key features of DS, All DS individuals develop early-onset Alzheimer＇s disease-like neuropathology. Intersectin 1 gene is localized on human chromosome 21, the critical region of DS, and it has higher expression in the brain of DS patients than in normal individuals. So fully understanding functions of intersectin 1 is critical for revealing the pathogenesis of DS. Intersectin 1 protein has two isoforms： intersectin 1-L and intersectin 1-S. This review will focus 1 in the central nervous system. on the distribution, expression characters and functions of intersectin
Slit2/Robo1 is a conserved ligand-receptor system,which greatly affects the distribution,migration,axon guidance and branching of neuron cells.Slit2 and its transmembrane receptor Robo1 have different distribution patterns in gliomas.The expression of Slit2 is at very low levels in pilocytic astrocytoma,fibrillary astrocytoma and glioblastoma,while Robo1 is highly expressed in different grades of gliomas at both mRNA and protein levels.Acquisition of insidious invasiveness by malignant glioma cells involves multiple genetic alterations in signaling pathways.Although the specific mechanisms of tumor-suppressive effect of Slit2/Robo1 have not been elucidated,it has been proved that Slit2/Robo1 signaling inhibits glioma cellmigration and invasion by inactivation of Cdc42-GTP.With the research development on the molecular mechanisms of Slit2/Robo1 signaling in glioma invasion and migration,Slit2/Robo1 signaling may become a potential target for glioma prevention and treatment.
