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Analyzing Large Protein Complexes by Structural Mass Spectrometry
15:35

Analyzing Large Protein Complexes by Structural Mass Spectrometry

Published on: June 19, 2010

The complete primary structure of mouse 20S proteasomes

L A Elenich1, D Nandi, A E Kent

  • 1Howard Hughes Medical Institute, and Departments of Molecular Genetics and Cell Biology, University of Cincinnati, 231 Bethesda Avenue, Cincinnati, OH 45267-0524, USA.

Immunogenetics
|August 7, 1999
PubMed

The proteasome is a large multicatalytic proteinase that plays a role in the generation of peptides for presentation by major histocompatibility complex class I molecules. The 20S proteolytic core of mammalian proteasomes is assembled from a group of 17 protein subunits that generate a distinctive pattern of spots upon two-dimensional gel electrophoresis. The genes for most of these subunits have been cloned from humans and rats. We isolated cDNA clones for the mouse orthologues of ten of the subunits [PSMA1 (C2), PSMA2 (C3), PSMA3 (C8), PSMA4 (C9), PSMA5 (ZETA), PSMA6 (IOTA), PSMA7 (C6-I), PSMB2 (C7-I), PSMB3 (C10-II), and PSMB5 (X)] to complete the cloning of all of the mouse subunits. Using antisera raised against these subunits or their orthologues, we verified the identity of these proteins by two-dimensional NEPHGE-PAGE.

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