Molecular Analysis of the Human GAR1 Gene

A Candidate Gene for Retinal Degeneration
  • Michelle D. Ardell
  • Ajay Makhija
  • Steven J. Pittler


A bovine glutamic acid rich protein (garp) was first reported as a soluble protein of unknown function which copurified with cGMP phosphodiesterase from rod outer segments (1). Characterization of bovine retina cDNA clones encoding garp identified a 65 kD protein with a high overall glutamate composition (24%), including one 109 amino acid domain near the C-terminus especially enriched (68/109 residues) in glutamate. This domain contained four repeats of a glutamate-rich 11 amino acid residue sequence (undecapeptide) and two repeats of a 26 amino acid peptide also rich in glutamic acid. Antibodies against a decamer corresponding to the undecapeptide from the glutamate rich region recognized a 65 kD protein in crude rod outer segment extracts. Northern analysis of poly A+ RNA from a variety of bovine tissues identified a 2.4 kb transcript only in the retina sample, suggesting that the expression may be retina-specific. More recently it was shown that garp is part of the 240 kD integral membrane protein complex that forms part of the cGMP-gated cation channel of bovine rod outer segments, thus identifing it as a third subunit (y) of the channel (2).


Plexiform Layer Retinal Degeneration Bovine Retina Preimmune Seron cGMP Phosphodiesterase 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


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Copyright information

© Springer Science+Business Media New York 1995

Authors and Affiliations

  • Michelle D. Ardell
    • 1
  • Ajay Makhija
    • 1
  • Steven J. Pittler
    • 1
    • 2
  1. 1.Department of Biochemistry and Molecular BiologyUniversity of South Alabama College of MedicineMobileUSA
  2. 2.Department of OphthalmologyUniversity of South Alabama College of MedicineMobileUSA

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