L-serine and glycine serve as major astroglia-derived trophic factors for cerebellar Purkinje neurons.
Glial cells support the survival and development of central neurons through the supply of trophic factors. Here we demonstrate that l-serine (l-Ser) and glycine (Gly) also are glia-derived trophic factors. These amino acids are released by astroglial cells and promote the survival, dendritogenesis, and electrophysiological development of cultured cerebellar Purkinje neurons. Although l-Ser and Gly are generally classified as nonessential amino acids, 3-phosphoglycerate dehydrogenase (3PGDH), a key enzyme for their biosynthesis, is not expressed in Purkinje neurons. By contrast, the Bergman glia, a native astroglia in the cerebellar cortex, highly expresses 3PGDH. These data suggest that l-Ser and Gly mediate the trophic actions of glial cells on Purkinje neurons.
Furuya
S
S
Neuronal Circuit Mechanisms Research Group, Brain Science Institute, Frontier Research Program, RIKEN, Wako, Saitama 351-0198, Japan. furuyash@postman.riken.go.jp
Tabata
T
T
Mitoma
J
J
Yamada
K
K
Yamasaki
M
M
Makino
A
A
Yamamoto
T
T
Watanabe
M
M
Kano
M
M
Hirabayashi
Y
Y
D000818:Animals; D002237:Carbohydrate Dehydrogenases / Q000235:genetics / Q000378:metabolism; D002478:Cells, Cultured; D018846:Excitatory Amino Acids / Q000502:physiology; D005998:Glycine / Q000502:physiology*; D007150:Immunohistochemistry; D017403:In Situ Hybridization; D008564:Membrane Potentials; D008854:Microscopy, Electron; D050543:Phosphoglycerate Dehydrogenase; D011689:Purkinje Cells / Q000166:cytology* / Q000201:enzymology / Q000502:physiology; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D017208:Rats, Wistar; D012694:Serine / Q000502:physiology*
D018846:Excitatory Amino Acids; D012333:RNA, Messenger; D012694:Serine; D002237:Carbohydrate Dehydrogenases; D050543:Phosphoglycerate Dehydrogenase; D005998:Glycine