Recoverin, a photoreceptor-specific calcium-binding protein, is expressed by the tumor of a patient with cancer-associated retinopathy.

• DOI: 10.1073/pnas.92.20.9176
• Publication Date: 2006-05-31T13:21:01Z
• Authors: A S Polans; D Witkowska; T L Haley; D Amundson; L Baizer; G Adamus
• Keywords: Recoverin

Recoverin is a member of the EF-hand family calcium-binding proteins involved in transduction light by vertebrate photoreceptors. also was identified as an autoantigen degenerative disease retina known cancer-associated retinopathy (CAR), paraneoplastic syndrome whereby immunological events lead to degeneration photoreceptors some individuals with cancer. In this study, we demonstrate that recoverin expressed lung tumor CAR patient but not similar tumors obtained from without associated retinopathy. intially Western blot analysis patient's biopsy tissue using anti-recoverin antibodies generated against different regions molecule. addition, cultured cells recoverin, demonstrated reverse transcription-PCR RNA extracted cells. The immunodominant region determined study solid-phase immunoassay employing overlapping heptapeptides encompassing entire sequence. Two linear stretches amino acids (residues 64-70, Lys-Ala-Tyr-Ala-Gln-His-Val; and 48-52, Gln-Phe-Gln-Ser-Ile) made up major determinants. One same molecule 64-70) uniquely immunopathogenic, causing photoreceptor upon immunization Lewis rats corresponding peptide. These data neural antigen more than likely responsible for vision loss patients establish one few autoimmune-mediated diseases which specific self-antigen known.