Yeast ribosomal protein L26 is located at the ribosomal subunit interface as determined by chemical cross-linking.
Previous studies suggested that yeast ribosomal protein L26 was a candidate for the ribosomal subunit interface region. The present study used protein-protein cross-linking to identify neighboring proteins in intact 80S ribosomes of Saccharomyces cerevisiae. To facilitate identification of cross-linked pairs involving L26, 80S ribosomes were first treated with 5-iodoacetamidofluorescein to selectively label L26. Protein cross-links were produced with dithiobis[succinimidyl] propionate or N-succinimidyl-3-[2-pyridyldithio] propionate and analyzed by electrophoresis on two-dimensional diagonal polyacrylamide gels containing SDS. L26 was detected under UV and its cross-linked partner, detectable after staining with Coomassie blue, was located below the diagonal and was coincident with L26 on a single vertical axis. The identity of the partner was determined by its co-migration with 60S and 40S ribosomal protein markers on two-dimensional gels. Two protein pairs involving L26 and 40S subunit proteins were identified. The finding provided experimental evidence to support that L26 is located at the ribosomal subunit interface. A model that incorporates the present findings and the published data on intra-subunit protein pairs is proposed for the yeast 80S ribosome.
Department of Biochemistry, University of Texas Health Science Center, San Antonia 78284-7760, USA.
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Villarreal
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JC
Lee
D003432:Cross-Linking Reagents; D004591:Electrophoresis, Polyacrylamide Gel; D005452:Fluoresceins; D012269:Ribosomal Proteins / Q000032:analysis / Q000737:chemistry* / Q000378:metabolism; D012270:Ribosomes / Q000737:chemistry* / Q000378:metabolism; D012441:Saccharomyces cerevisiae / Q000737:chemistry* / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins; D013388:Succinimides
D003432:Cross-Linking Reagents; D005452:Fluoresceins; C489218:RPL26A protein, S cerevisiae; C489219:RPL26B protein, S cerevisiae; D012269:Ribosomal Proteins; D029701:Saccharomyces cerevisiae Proteins; D013388:Succinimides; C018151:N-succinimidyl 3-(2-pyridyldithio)propionate; C015296:5-iodoacetamidofluorescein; C011240:dithiobis(succinimidylpropionate)