Autoantibodies against a serine tRNA-protein complex implicated in cotranslational selenocysteine insertion.

Gelpi, C; Sontheimer, E J; Rodriguez-Sanchez, J L

Autoantibodies against a serine tRNA-protein complex implicated in cotranslational selenocysteine insertion.

Authors

Gelpi, C

Sontheimer, E J

Rodriguez-Sanchez, J L

Publisher

National Academy of Sciences

Description

We describe an autoantibody specificity present in a subgroup of patients with a severe form of autoimmune chronic active hepatitis. These antibodies precipitate a 90-nucleotide RNA from human whole cell extracts and recognize a 48-kDa polypeptide in immunoblotting assays. The RNA is a UGA suppressor serine tRNA that carries selenocysteine (tRNA[Ser]Sec)), as shown by sequence analysis. The protein does not appear to be seryl-tRNA synthetase; rather, it is an excellent candidate for a factor involved in cotranslational selenocysteine incorporation in human cells. IMAGES: