title: Human t-DARPP is induced during striatal development.
abstract: Human Dopamine- and cAMP-regulated phosphoprotein of molecular weight 32kDa (DARPP-32, also known as PPP1R1B) gene codes for different transcripts that are mainly translated into two DARPP-32 protein isoforms, full length (fl)-DARPP-32 and truncated (t)-DARPP. The t-DARPP lacks the first 36 residues at the N-terminal, which alters its function. In the central nervous system, fl-DARPP-32 is highly expressed in GABAergic striatal medium spiny neurons (MSNs), where it integrates dopaminergic and glutamatergic input signaling. However, no information about human DARPP-32 isoform expression during MSNs maturation is available. In this study, our aim is to determine the expression of the two DARPP-32 isoforms in human fetal and adult striatal samples. We show that DARPP-32 isoform expression is differentially regulated during human striatal development, with the t-DARPP isoform being virtually absent from whole ganglionic eminence (WGE) and highly induced in the adult striatum (in both caudate and putamen). We next compared the four most common anti-DARPP-32 antibodies used in human specimens, to study their recognition of the two isoforms in fetal and adult human striatal samples by western blot and immunohistochemistry. The four antibodies specifically identify the fl-DARPP-32 in both fetal and adult samples, while t-DARPP form was only detected in adult striatal samples. In addition, the lack of t-DARPP recognition in human adult striatum by the antibody generated against the full-length domain produces in turn different efficacy by immunohistochemical analysis. In conclusion, our results show that expression of human DARPP-32 protein isoforms depends on the striatal neurodevelopmental stage with t-DARPP being specific for the human adult striatum.
authors.affiliation: Laboratory of Stem Cells and Regenerative Medicine, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, University of Barcelona, Barcelona, Spain; August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain; Networked Biomedical Research Centre for NeuroDegenerative Disorders (CIBERNED), Spain. Electronic address: mstraccia@ub.edu.
authors.forename: Marco
authors.initials: M
authors.lastname: Straccia
authors.affiliation: Laboratory of Stem Cells and Regenerative Medicine, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, University of Barcelona, Barcelona, Spain; August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain; Networked Biomedical Research Centre for NeuroDegenerative Disorders (CIBERNED), Spain.
authors.forename: Jordi
authors.initials: J
authors.lastname: Carrere
authors.affiliation: Cardiff Brain Repair Group, Schools of Biosciences and Medicine, and Institute of Psychological Medicine and Clinical Neurology, Cardiff University, Cardiff, UK.
authors.forename: Anne E
authors.initials: AE
authors.lastname: Rosser
authors.affiliation: Laboratory of Stem Cells and Regenerative Medicine, Department of Biomedical Sciences, Faculty of Medicine and Health Sciences, University of Barcelona, Barcelona, Spain; August Pi i Sunyer Biomedical Research Institute (IDIBAPS), Barcelona, Spain; Networked Biomedical Research Centre for NeuroDegenerative Disorders (CIBERNED), Spain; Research and Development Unit, Cell Therapy Program, Faculty of Medicine and Health Sciences, University of Barcelona, Barcelona, Spain. Electronic address: jmcanals@ub.edu.
authors.forename: Josep M
authors.initials: JM
authors.lastname: Canals
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D015153:Blotting, Western; D003342:Corpus Striatum / Q000166:cytology / Q000196:embryology / Q000254:growth & development* / Q000378:metabolism*; D051937:Dopamine and cAMP-Regulated Phosphoprotein 32 / Q000378:metabolism*; D005260:Female; D059330:GABAergic Neurons / Q000166:cytology / Q000378:metabolism; D006801:Humans; D007150:Immunohistochemistry; D008297:Male; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D020033:Protein Isoforms; D012333:RNA, Messenger / Q000378:metabolism; D017386:Sequence Homology, Amino Acid
chemical_list: D051937:Dopamine and cAMP-Regulated Phosphoprotein 32; C497928:PPP1R1B protein, human; D020033:Protein Isoforms; D012333:RNA, Messenger
keywords: DARPP-32; Huntington’s disease; human development; medium spiny neurons; neurodevelopment; striatum