TY - JOUR

T1 - Quaternary structure of the ATPase complex of human 26S proteasomes determined by chemical cross-linking.

AU - Hartmann-Petersen, R

AU - Tanaka, K

AU - Hendil, K B

N1 - Keywords: Adenosine Triphosphatases; Cross-Linking Reagents; Cysteine Endopeptidases; Hela Cells; Humans; Microscopy, Electron; Multienzyme Complexes; Peptide Hydrolases; Precipitin Tests; Proteasome Endopeptidase Complex; Protein Binding; Protein Structure, Quaternary; Sodium Dodecyl Sulfate

PY - 2001

Y1 - 2001

N2 - The 26S proteasome is the major protease responsible for nonlysosomal protein degradation in eukaryotic cells. The enzyme is composed of two subparticles: the 20S proteasome, and a 19S regulatory particle (PA700) which binds to the ends of the 20S proteasome cylinder and accounts for ATP dependence and substrate specificity. Among the approximately 18 subunits of PA700 regulator, six are ATPases. The ATPases presumably recognize, unfold, and translocate substrates into the interior of the 26S proteasome. It is generally believed that the ATPases form a hexameric ring. By means of chemical cross-linking, immunoprecipitation, and blotting, we have determined that the ATPases are organized in the order S6-S6'-S10b-S8-S4-S7. Additionally, we found cross-links between the ATPase S10b and the 20S proteasome subunit alpha6. Together with the previously known interaction between S8 and alpha1 and between S4 and alpha7, these data establish the relative orientations of ATPases with respect to the 20S proteasome.

AB - The 26S proteasome is the major protease responsible for nonlysosomal protein degradation in eukaryotic cells. The enzyme is composed of two subparticles: the 20S proteasome, and a 19S regulatory particle (PA700) which binds to the ends of the 20S proteasome cylinder and accounts for ATP dependence and substrate specificity. Among the approximately 18 subunits of PA700 regulator, six are ATPases. The ATPases presumably recognize, unfold, and translocate substrates into the interior of the 26S proteasome. It is generally believed that the ATPases form a hexameric ring. By means of chemical cross-linking, immunoprecipitation, and blotting, we have determined that the ATPases are organized in the order S6-S6'-S10b-S8-S4-S7. Additionally, we found cross-links between the ATPase S10b and the 20S proteasome subunit alpha6. Together with the previously known interaction between S8 and alpha1 and between S4 and alpha7, these data establish the relative orientations of ATPases with respect to the 20S proteasome.

U2 - 10.1006/abbi.2000.2178

DO - 10.1006/abbi.2000.2178

M3 - Journal article

C2 - 11361004

VL - 386

SP - 89

EP - 94

JO - Archives of Biochemistry and Biophysics

JF - Archives of Biochemistry and Biophysics

SN - 0003-9861

IS - 1

ER -