rAAV-mediated subcellular targeting of optogenetic tools in retinal ganglion cells in vivo

PLoS One. 2013 Jun 14;8(6):e66332. doi: 10.1371/journal.pone.0066332. Print 2013.

Abstract

Expression of optogenetic tools in surviving inner retinal neurons to impart retinal light sensitivity has been a new strategy for restoring vision after photoreceptor degeneration. One potential approach for restoring retinal light sensitivity after photoreceptor degeneration is to express optogenetic tools in retinal ganglion cells (RGCs). For this approach, restoration of ON and OFF center-surround receptive fields in RGCs, a key feature of visual information processing, may be important. A possible solution is to differentially express depolarizing and hyperpolarizing optogenetic tools, such as channelrhodopsin-2 and halorhodopsin, to the center and peripheral regions of the RGC dendritic field by using protein targeting motifs. Recombinant adeno-associated virus (rAAV) vectors have proven to be a powerful vehicle for in vitro and in vivo gene delivery, including in the retina. Therefore, the search for protein targeting motifs that can achieve rAAV-mediated subcellular targeted expression would be particularly valuable for developing therapeutic applications. In this study, we identified two protein motifs that are suitable for rAAV-mediated subcellular targeting for generating center-surround receptive fields while reducing the axonal expression in RGCs. Resulting morphological dendritic field and physiological response field by center-targeting were significantly smaller than those produced by surround-targeting. rAAV motif-mediated protein targeting could also be a valuable tool for studying physiological function and clinical applications in other areas of the central nervous system.

Publication types

  • Research Support, N.I.H., Extramural
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Motifs
  • Amino Acid Sequence
  • Animals
  • Bacterial Proteins / biosynthesis
  • Bacterial Proteins / genetics
  • Cell Polarity
  • Channelrhodopsins
  • Dependovirus / genetics*
  • Gene Expression
  • Genetic Therapy / methods
  • Green Fluorescent Proteins / biosynthesis
  • Green Fluorescent Proteins / genetics
  • Luminescent Proteins / biosynthesis
  • Luminescent Proteins / genetics
  • Mice
  • Mice, Inbred C57BL
  • Mice, Transgenic
  • Molecular Sequence Data
  • Optogenetics
  • Protein Sorting Signals
  • Protein Transport
  • Receptors, Cell Surface / chemistry
  • Recombinant Fusion Proteins / biosynthesis
  • Recombinant Fusion Proteins / genetics
  • Retinal Ganglion Cells / metabolism*
  • Transduction, Genetic

Substances

  • Bacterial Proteins
  • Channelrhodopsins
  • Luminescent Proteins
  • Protein Sorting Signals
  • Receptors, Cell Surface
  • Recombinant Fusion Proteins
  • yellow fluorescent protein, Bacteria
  • Green Fluorescent Proteins