Expression of high affinity choline transporter during mouse development in vivo and its upregulation by NGF and BMP-4 in vitro.
An important feature of cholinergic neurons is high-affinity choline transport, which allows them to reuse choline for the synthesis of ACh needed to support cholinergic neurotransmission. The choline transporter, designated CHT, was recently cloned. We applied RT/PCR to monitor the expression of CHT in the developing mouse CNS from embryonic day 14 (E14) to postnatal day 30 (P30). We found that CHT was expressed early in development, predominantly in the regions containing cholinergic neurons. In the spinal cord, CHT mRNA was present at close to adult levels at the earliest time point examined (E14) and showed almost no changes after birth. In the striatum and the septum, CHT mRNA increased steadily during embryonic stages and leveled off after birth. Surprisingly, CHT mRNA expression was also detected in other brain regions, notably in the cerebellum, where it peaked on E19, and then rapidly declined during postnatal development. CHT protein was detected by Western blotting as a band of apparent molecular weight of 70 kDa. The accumulation of this protein during development lagged behind mRNA accumulation in all tissues. We also examined the effects of NGF and BMP-4, the potent inducers of choline acetyltransferase and vesicular acetylcholine transporter genes, on CHT expression. Both factors increased CHT mRNA accumulation in primary septal cultures. The effect of NGF was dependent on the PI3K signaling, as it was abolished by the PI3K inhibitor LY294002. This result indicates that some of the signals regulating other cholinergic-specific genes also control CHT expression.
Berse
Brygida
B
Department of Pathology and Laboratory Medicine, Boston University School of Medicine, 715 Albany Street, Room L-808C, Boston, MA 02118, USA. berse@bu.edu
Szczecinska
Weronika
W
Lopez-Coviella
Ignacio
I
Madziar
Beata
B
Zemelko
Victoria
V
Kaminski
Rafal
R
Kozar
Katarzyna
K
Lips
Katrin S
KS
Pfeil
Uwe
U
Blusztajn
Jan Krzysztof
JK
D000109:Acetylcholine / Q000378:metabolism*; D000818:Animals; D000831:Animals, Newborn; D055415:Bone Morphogenetic Protein 4; D019485:Bone Morphogenetic Proteins / Q000378:metabolism* / Q000494:pharmacology; D001921:Brain / Q000196:embryology / Q000254:growth & development / Q000378:metabolism; D002478:Cells, Cultured; D002490:Central Nervous System / Q000196:embryology / Q000254:growth & development / Q000378:metabolism*; D002795:Choline O-Acetyltransferase / Q000378:metabolism; D002799:Cholinergic Fibers / Q000187:drug effects / Q000378:metabolism*; D018507:Gene Expression Regulation, Developmental / Q000187:drug effects / Q000502:physiology; D007150:Immunohistochemistry; D026901:Membrane Transport Proteins / Q000235:genetics* / Q000378:metabolism; D051379:Mice; D020932:Nerve Growth Factor / Q000378:metabolism* / Q000494:pharmacology; D009474:Neurons / Q000187:drug effects / Q000378:metabolism; D019869:Phosphatidylinositol 3-Kinases / Q000378:metabolism; D000081082:Phosphoinositide-3 Kinase Inhibitors; D012333:RNA, Messenger / Q000187:drug effects / Q000378:metabolism; D013116:Spinal Cord / Q000196:embryology / Q000254:growth & development / Q000378:metabolism; D015854:Up-Regulation / Q000187:drug effects / Q000502:physiology; D050494:Vesicular Acetylcholine Transport Proteins
D000109:Acetylcholine; D055415:Bone Morphogenetic Protein 4; D019485:Bone Morphogenetic Proteins; D002795:Choline O-Acetyltransferase; D026901:Membrane Transport Proteins; D020932:Nerve Growth Factor; D019869:Phosphatidylinositol 3-Kinases; D000081082:Phosphoinositide-3 Kinase Inhibitors; D012333:RNA, Messenger; D050494:Vesicular Acetylcholine Transport Proteins; C525810:Bmp4 protein, mouse; C488255:CHT1 protein, mouse; C493460:Slc18a3 protein, mouse