title: Phospholipase Cbeta4 expression identifies a novel subset of unipolar brush cells in the adult mouse cerebellum.
abstract: Unipolar brush cells (UBCs) are glutamatergic cerebellar interneurons of the granular layer. Previous studies have shown that there are two distinct subsets of UBCs present in the mice cerebellar cortex: calcium-binding protein calretinin (CR) positive and metabotropic glutamate receptor (mGluR)1alpha positive. In this study, we identify phospholipase C (PLC) beta4 as an antigenic marker of a novel subset of UBCs. Double immunolabeling reveals that none of the CR+ subset expresses PLCbeta4. In contrast, most members of the mGluR1alpha subset also express PLCbeta4. In addition, 65% of the PLCbeta4+ subset does not express mGluR1alpha. Thus, there are three distinct UBC subsets in the mouse cerebellum: CR+/PLCbeta4-/mGluR1alpha-, PLCbeta4+/mGluR1alpha-/CR-, and mGluR1alpha+/PLCbeta4+/CR-. Each has a different topographical distribution, both between lobules and mediolaterally within the vermis. The development of PLCbeta4 expression in UBCs is exclusively postnatal--first seen only at P12 and mature at about 3 weeks. A distinct subset of PLCbeta4+ UBCs is also present in primary cerebellar cultures.
authors.affiliation: Department of Cell Biology & Anatomy, Hotchkiss Brain Institute, Faculty of Medicine, University of Calgary, Calgary, Alberta T2N 4N1, Canada.
authors.forename: Seung-Hyuk
authors.initials: SH
authors.lastname: Chung
authors.forename: Hassan
authors.initials: H
authors.lastname: Marzban
authors.forename: Masahiko
authors.initials: M
authors.lastname: Watanabe
authors.forename: Richard
authors.initials: R
authors.lastname: Hawkes
mesh_terms: D000818:Animals; D000831:Animals, Newborn; D064032:Calbindin 2; D002531:Cerebellum / Q000166:cytology*; D004622:Embryo, Mammalian; D018507:Gene Expression Regulation, Developmental / Q000502:physiology; D049452:Green Fluorescent Proteins / Q000235:genetics; D007395:Interneurons / Q000145:classification / Q000378:metabolism*; D008164:Luminescent Proteins / Q000235:genetics; D051379:Mice; D008810:Mice, Inbred C57BL; D008822:Mice, Transgenic; D009433:Neural Inhibition / Q000502:physiology*; D009924:Organ Culture Techniques; D054799:Phospholipase C beta / Q000378:metabolism*; D018094:Receptors, Metabotropic Glutamate / Q000378:metabolism; D064030:S100 Calcium Binding Protein G / Q000378:metabolism
chemical_list: C576511:Calb2 protein, mouse; D064032:Calbindin 2; D008164:Luminescent Proteins; D018094:Receptors, Metabotropic Glutamate; D064030:S100 Calcium Binding Protein G; C485184:enhanced green fluorescent protein; C104077:metabotropic glutamate receptor type 1; D049452:Green Fluorescent Proteins; D054799:Phospholipase C beta; C518043:Plcb4 protein, mouse