Transcriptional repression of Plxnc1 by Lmx1a and Lmx1b directs topographic dopaminergic circuit formation

Nat Commun. 2017 Oct 16;8(1):933. doi: 10.1038/s41467-017-01042-0.

Abstract

Mesodiencephalic dopamine neurons play central roles in the regulation of a wide range of brain functions, including voluntary movement and behavioral processes. These functions are served by distinct subtypes of mesodiencephalic dopamine neurons located in the substantia nigra pars compacta and the ventral tegmental area, which form the nigrostriatal, mesolimbic, and mesocortical pathways. Until now, mechanisms involved in dopaminergic circuit formation remained largely unknown. Here, we show that Lmx1a, Lmx1b, and Otx2 transcription factors control subtype-specific mesodiencephalic dopamine neurons and their appropriate axon innervation. Our results revealed that the expression of Plxnc1, an axon guidance receptor, is repressed by Lmx1a/b and enhanced by Otx2. We also found that Sema7a/Plxnc1 interactions are responsible for the segregation of nigrostriatal and mesolimbic dopaminergic pathways. These findings identify Lmx1a/b, Otx2, and Plxnc1 as determinants of dopaminergic circuit formation and should assist in engineering mesodiencephalic dopamine neurons capable of regenerating appropriate connections for cell therapy.Midbrain dopaminergic neurons (mDAs) in the VTA and SNpc project to different regions and form distinct circuits. Here the authors show that transcription factors Lmx1a, Lmx1b, and Otx2 control the axon guidance of mDAs and the segregation of mesolimbic and nigrostriatal dopaminergic pathways.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Antigens, CD / genetics
  • Antigens, CD / metabolism
  • Axons / physiology
  • Dopaminergic Neurons / metabolism
  • Female
  • Gene Expression Regulation
  • LIM-Homeodomain Proteins / genetics
  • LIM-Homeodomain Proteins / metabolism*
  • Male
  • Mice, Inbred C57BL
  • Mice, Knockout
  • Mice, Transgenic
  • Nerve Tissue Proteins / genetics*
  • Nerve Tissue Proteins / metabolism
  • Otx Transcription Factors / genetics
  • Otx Transcription Factors / metabolism
  • Receptors, Cell Surface / genetics*
  • Receptors, Cell Surface / metabolism
  • Semaphorins / genetics
  • Semaphorins / metabolism
  • Transcription Factors / genetics
  • Transcription Factors / metabolism*
  • Ventral Tegmental Area / physiology

Substances

  • Antigens, CD
  • LIM homeobox transcription factor 1 beta
  • LIM-Homeodomain Proteins
  • Lmx1a protein, mouse
  • Nerve Tissue Proteins
  • Otx Transcription Factors
  • Otx2 protein, mouse
  • Plxna3 protein, mouse
  • Receptors, Cell Surface
  • Sema7a protein, mouse
  • Semaphorins
  • Transcription Factors