April 2014
Volume 55, Issue 13
Free
ARVO Annual Meeting Abstract  |   April 2014
Self-association does not play a decisive role in the distribution of arrestin-1 in dark-adapted rods
Author Affiliations & Notes
  • Vsevolod V Gurevich
    Pharmacology, Vanderbilt University, Nashville, TN
  • Sergey A Vishnivetskiy
    Pharmacology, Vanderbilt University, Nashville, TN
  • Seunghyi Kook
    Pharmacology, Vanderbilt University, Nashville, TN
  • Eugenia Gurevich
    Pharmacology, Vanderbilt University, Nashville, TN
  • Footnotes
    Commercial Relationships Vsevolod Gurevich, None; Sergey Vishnivetskiy, None; Seunghyi Kook, None; Eugenia Gurevich, None
  • Footnotes
    Support None
Investigative Ophthalmology & Visual Science April 2014, Vol.55, 3029. doi:
  • Views
  • Share
  • Tools
    • Alerts
      ×
      This feature is available to authenticated users only.
      Sign In or Create an Account ×
    • Get Citation

      Vsevolod V Gurevich, Sergey A Vishnivetskiy, Seunghyi Kook, Eugenia Gurevich; Self-association does not play a decisive role in the distribution of arrestin-1 in dark-adapted rods. Invest. Ophthalmol. Vis. Sci. 2014;55(13):3029.

      Download citation file:


      © ARVO (1962-2015); The Authors (2016-present)

      ×
  • Supplements
Abstract

Purpose: In dark-adapted rods the bulk of arrestin-1 is localized away from the outer segment, where its key binding partner rhodopsin resides. Two factors were proposed to contribute to this counter-intuitive localization of arrestin-1: its binding to microtubules, concentrated in the inner segment, perinucler area, and synaptic terminals, or relatively large size of arrestin-1 dimers and tetramers, which it readily forms at physiological expression level.

Methods: We created transgenic mice expressing constitutively monomeric arrestin-1 mutant at different levels, from 10 to ~300% of normal WT arrestin-1 concentration in rods. Since the mutant binds both rhodopsin and microtubules normally, this eliminated a single factor that can contribute to arrestin-1 distribution, its self-association. Arrestin distribution in fixed eyes from dark-adapted WT and transgenic mice expressing this mutant was compared by immunohistochemistry.

Results: The distribution of constitutively monomeric arrestin-1 in dark-adapted rods was remarkably similar to the distribution of WT arrestin-1, which robustly self-associates, so that the majority of arestin-1 complement exists as a tetramer in WT rods in the dark. Self-association-deficient arrestin-1 was largely localized to the inner segments, cell bodies, and synaptic terminals, just like WT protein, with relatively small fraction present in the outer segments.

Conclusions: These data suggest that the size of arestin-1 dimers and tetramers, which are expected to be too large to fit into intra-discal spaces in the outer segments, is not the dominant factor keeping arrestin-1 away from this compartment in the dark. Thus, arrestin-1 distribution in dark-adapted photoreceptors is largely determined by its interactions with to microtubules and/or other binding partners absent in the outer segments. Supported by NIH grant EY011500.

Keywords: 648 photoreceptors • 659 protein structure/function • 714 signal transduction  
×
×

This PDF is available to Subscribers Only

Sign in or purchase a subscription to access this content. ×

You must be signed into an individual account to use this feature.

×