title: Satb2-independent acquisition of the cholinergic sudomotor phenotype in rodents.
abstract: Expression of Satb2 (Special AT-rich sequence-binding protein-2) elicits expression of the vesicular acetylcholine transporter (VAChT) and choline acetyltransferase (ChAT) in cultured rat sympathetic neurons exposed to soluble differentiation factors. Here, we determined whether or not Satb2 plays a similar role in cholinergic differentiation in vivo, by comparing the postnatal profile of Satb2 expression in the rodent stellate ganglion to that of VAChT and ChAT. Throughout postnatal development, VAChT and ChAT were found to be co-expressed in a numerically stable subpopulation of rat stellate ganglion neurons. Nerve fibers innervating rat forepaw sweat glands on P1 were VAChT immunoreactive, while ChAT was detectable at this target only after P5. The postnatal abundance of VAChT transcripts in the stellate ganglion was at maximum already on P1, whereas ChAT mRNA levels increased from low levels on P1 to reach maximum levels between P5 and P21. Satb2 mRNA was detected in cholinergic neurons in the stellate ganglion beginning with P8, thus coincident with the onset of unequivocal detection of ChAT immunoreactivity in forepaw sweat gland endings. Satb2 knockout mice exhibited no change in the P1 cholinergic VAChT/ChAT co-phenotype in stellate ganglion neurons. Thus, cholinergic phenotype maturation involves first, early target (sweat-gland)-independent expression and trafficking of VAChT, and later, potentially target- and Satb2-dependent elevation of ChAT mRNA and protein transport into sweat gland endings. In rat sudomotor neurons that, unlike mouse sudomotor neurons, co-express calcitonin gene-related peptide (CGRP), Satb2 may also be related to the establishment of species-specific neuropeptide co-phenotypes during postnatal development.
authors.affiliation: Department of Molecular Neuroscience, Institute of Anatomy and Cell Biology, Philipps-University, Robert-Koch-Straße 8, 35037, Marburg, Germany, schuetzb@staff.uni-marburg.de.
authors.forename: Burkhard
authors.initials: B
authors.lastname: Schütz
authors.forename: Martin K-H
authors.initials: MK
authors.lastname: Schäfer
authors.forename: Markus
authors.initials: M
authors.lastname: Gördes
authors.forename: Lee E
authors.initials: LE
authors.lastname: Eiden
authors.forename: Eberhard
authors.initials: E
authors.lastname: Weihe
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D000918:Antibody Specificity; D015415:Biomarkers / Q000378:metabolism; D059329:Cholinergic Neurons / Q000378:metabolism*; D005121:Extremities / Q000294:innervation; D005260:Female; D005786:Gene Expression Regulation; D008297:Male; D036961:Matrix Attachment Region Binding Proteins / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D008807:Mice, Inbred BALB C; D009043:Motor Activity; D010455:Peptides / Q000378:metabolism; D010641:Phenotype; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D017208:Rats, Wistar; D013233:Stellate Ganglion / Q000378:metabolism; D013545:Sweat Glands / Q000294:innervation; D013564:Sympathetic Nervous System / Q000378:metabolism; D013997:Time Factors; D014157:Transcription Factors / Q000172:deficiency / Q000235:genetics / Q000378:metabolism*; D050494:Vesicular Acetylcholine Transport Proteins
chemical_list: D015415:Biomarkers; D036961:Matrix Attachment Region Binding Proteins; D010455:Peptides; D012333:RNA, Messenger; C501473:SATB2 protein, mouse; C586446:SATB2 protein, rat; D014157:Transcription Factors; D050494:Vesicular Acetylcholine Transport Proteins