Sequential generation of olfactory bulb glutamatergic neurons by Neurog2-expressing precursor cells

Neural Dev. 2011 Apr 5:6:12. doi: 10.1186/1749-8104-6-12.

Abstract

Background: While the diversity and spatio-temporal origin of olfactory bulb (OB) GABAergic interneurons has been studied in detail, much less is known about the subtypes of glutamatergic OB interneurons.

Results: We studied the temporal generation and diversity of Neurog2-positive precursor progeny using an inducible genetic fate mapping approach. We show that all subtypes of glutamatergic neurons derive from Neurog2 positive progenitors during development of the OB. Projection neurons, that is, mitral and tufted cells, are produced at early embryonic stages, while a heterogeneous population of glutamatergic juxtaglomerular neurons are generated at later embryonic as well as at perinatal stages. While most juxtaglomerular neurons express the T-Box protein Tbr2, those generated later also express Tbr1. Based on morphological features, these juxtaglomerular cells can be identified as tufted interneurons and short axon cells, respectively. Finally, targeted electroporation experiments provide evidence that while the majority of OB glutamatergic neurons are generated from intrabulbar progenitors, a small portion of them originate from extrabulbar regions at perinatal ages.

Conclusions: We provide the first comprehensive analysis of the temporal and spatial generation of OB glutamatergic neurons and identify distinct populations of juxtaglomerular interneurons that differ in their antigenic properties and time of origin.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Animals, Genetically Modified
  • Basic Helix-Loop-Helix Transcription Factors / biosynthesis*
  • Basic Helix-Loop-Helix Transcription Factors / genetics*
  • DNA-Binding Proteins / biosynthesis
  • DNA-Binding Proteins / genetics
  • Electroporation
  • Eye Proteins / biosynthesis
  • Eye Proteins / genetics
  • Female
  • Glutamic Acid / physiology*
  • Green Fluorescent Proteins / genetics
  • Homeodomain Proteins / biosynthesis
  • Homeodomain Proteins / genetics
  • Image Processing, Computer-Assisted
  • Immunohistochemistry
  • In Situ Hybridization
  • Juxtaglomerular Apparatus / innervation
  • Mice
  • Nerve Tissue Proteins / biosynthesis*
  • Nerve Tissue Proteins / genetics*
  • Neural Stem Cells / metabolism*
  • Neural Stem Cells / physiology
  • Neurogenesis / genetics
  • Neurogenesis / physiology
  • Neurons / physiology*
  • Nuclear Proteins / biosynthesis
  • Nuclear Proteins / genetics
  • Olfactory Bulb / cytology
  • Olfactory Bulb / growth & development
  • Olfactory Bulb / physiology*
  • PAX6 Transcription Factor
  • Paired Box Transcription Factors / biosynthesis
  • Paired Box Transcription Factors / genetics
  • Repressor Proteins / biosynthesis
  • Repressor Proteins / genetics
  • Reverse Transcriptase Polymerase Chain Reaction
  • T-Box Domain Proteins / biosynthesis
  • T-Box Domain Proteins / genetics
  • Tamoxifen / pharmacology

Substances

  • Basic Helix-Loop-Helix Transcription Factors
  • DNA-Binding Proteins
  • Eomes protein, mouse
  • Eye Proteins
  • Homeodomain Proteins
  • Nerve Tissue Proteins
  • NeuN protein, mouse
  • Neurog2 protein, mouse
  • Nuclear Proteins
  • PAX6 Transcription Factor
  • Paired Box Transcription Factors
  • Pax6 protein, mouse
  • Repressor Proteins
  • T-Box Domain Proteins
  • Tbr1 protein, mouse
  • Tamoxifen
  • Green Fluorescent Proteins
  • Glutamic Acid