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Glial cell line-derived neurotrophic factor (GDNF) is a widely expressed protein in the central nervous system and peripheral tissues.Expression of GDNF mRNA is higher in glioma tissue than in normal tissue.Overexpression of GDNF mRNA is closely related to pathological changes in glial cells.Evidence shows that alternative splicing of GDWF can form a-pro-GDNF and p-pro-GDWF homologous splicing isomers,and that transposition of subcellular localization of these two isomers is present in nerve cells.Most current studies consider GDNF participating in the cell signal pathway as their goal,and investigate the pathogenesis of glioma or therapeutic strategies that control the downstream signaling factor GDNF.However,GDWF expression also contributes to its biological effects.A key point in studying the occurrence and development of glioma is to investigate the expression and secretion of a-pro-GDNF and p-pro-GDNF in the glial cells.First,we detected the expression of a-pro-GDNF and p-pro-GDNF in central nervous system tissues,including the hypothalamus,pituitary gland,hippocampus,olfactory bulb,substantia nigra,corpus striatum,and amygdaloid body using real-time PCR.In the different functional regions of the central nervous system,a-pro-GDNF and p-pro-GDNF were expressed simultaneously,but the expression pattern differs by region.Second,we further analyzed the GDWF subcellular localization signal,and investigated the association between expression of a- and P-pro-GDNF and GDNF overexpression.We reconstructed GDNF localization with targeted mutant vectors using ELISA,RNAi,and confocal microscopy.Isomers a-pro-GDNF and p-pro-GDNF localized differently in glioma cells,and the intracellular localization directly influenced pro-GDNF processing and secretion.The differences in signal peptide sequence between a-pro-GDNF and p-pro-GDNF peptide chains leads to excessive accumulation in the a-pro-GDNF precursor.GDNF can promote the migration and growth of glioma cells through the JNK,ERK-1/2,and p38 MAPK signal pathways,as well as accelerate cell proliferation through autocrine signaling.Therefore,overexpression of a-pro-GDNF plays an important role in the proliferation and migration of glioma cells.