Engineering visual arrestin-1 with special functional characteristics

J Biol Chem. 2013 Feb 1;288(5):3394-405. doi: 10.1074/jbc.M112.445437. Epub 2012 Dec 17.

Abstract

Arrestin-1 preferentially binds active phosphorylated rhodopsin. Previously, a mutant with enhanced binding to unphosphorylated active rhodopsin (Rh*) was shown to partially compensate for lack of rhodopsin phosphorylation in vivo. Here we showed that reengineering of the receptor binding surface of arrestin-1 further improves the binding to Rh* while preserving protein stability. In mammals, arrestin-1 readily self-associates at physiological concentrations. The biological role of this phenomenon can only be elucidated by replacing wild type arrestin-1 in living animals with a non-oligomerizing mutant retaining all other functions. We demonstrate that constitutively monomeric forms of arrestin-1 are sufficiently stable for in vivo expression. We also tested the idea that individual functions of arrestin-1 can be independently manipulated to generate mutants with the desired combinations of functional characteristics. Here we showed that this approach is feasible; stable forms of arrestin-1 with high Rh* binding can be generated with or without the ability to self-associate. These novel molecular tools open the possibility of testing of the biological role of arrestin-1 self-association and pave the way to elucidation of full potential of compensational approach to gene therapy of gain-of-function receptor mutations.

Publication types

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

MeSH terms

  • Animals
  • Arrestins / chemistry
  • Arrestins / genetics
  • Arrestins / metabolism*
  • Eye / metabolism*
  • HEK293 Cells
  • Humans
  • Mice
  • Models, Molecular
  • Mutant Proteins / chemistry
  • Mutant Proteins / metabolism
  • Mutation / genetics
  • Phosphates / metabolism
  • Protein Binding
  • Protein Engineering*
  • Protein Stability
  • Protein Structure, Tertiary
  • Rhodopsin / metabolism
  • Static Electricity
  • Temperature
  • beta-Arrestins

Substances

  • Arrestins
  • Mutant Proteins
  • Phosphates
  • beta-Arrestins
  • Rhodopsin