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Structural analysis of human Clusterin/ApoJ, part 1

ABSTRACT: The conserved human secreted glycoprotein Clusterin (aka Apolipoprotein-J, ApoJ) is an abundant component of body fluids such as blood plasma and cerebrospinal fluid. Clusterin is thought to function as an extracellular molecular chaperone stabilizing misfolded proteins in solution. In addition, clusterin forms lipoprotein complexes and fractions with HDL particles in plasma. Variants of the clusterin gene constitute the third most important risk factor for late-onset Alzheimer's disease. To better understand it structure and functions, the crystal structure of a mutant form of Clusterin was determined. In order to validate the structural data, hydrogen-deuterium exchange kinetics followed by pepsin proteolysis and mass spectrometry analysis of recombinant mutant and wildtype protein were performed (Part 1 of the deposited data). Based on the structure, rational mutants were designed and subjected to functional tests such as chaperone activity, cellular uptake and receptor binding and lipoprotein complex formation. In order to probe the conformation of Clusterin in the lipoprotein complex, free and lipid-bound protein were subjected to limited proteolysis with chymotrypsin and the resultant fragments analyzed by LC/MS proteomics (Part 2 of the deposited data).

INSTRUMENT(S):

ORGANISM(S): Homo Sapiens (human)

SUBMITTER: Andreas Bracher

LAB HEAD: F. Ulrich Hartl

PROVIDER: PXD057022 | Pride | 2025-07-22

REPOSITORIES: Pride

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			Action	DRS
	20220802_Clu-delta214-238_1000s_R1.raw.zip	Raw
	20220802_Clu-delta214-238_100s_R1.raw.zip	Raw
	20220802_Clu-delta214-238_10s_R1.raw.zip	Raw
	20220802_Clu-delta214-238_undeuterated_R1.raw.zip	Raw
	20220805_WT-Clu_1000s_R1.raw.zip	Raw

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Structural analysis of human Clusterin/ApoJ, part 2

Project description:The conserved human secreted glycoprotein Clusterin (aka Apolipoprotein-J, ApoJ) is an abundant component of body fluids such as blood plasma and cerebrospinal fluid. Clusterin is thought to function as an extracellular molecular chaperone stabilizing misfolded proteins in solution. In addition, Clusterin forms lipoprotein complexes and fractions with HDL particles in plasma. Variants of the Clusterin gene constitute the third most important genetic risk factor for late-onset Alzheimer's disease. To better understand its structure and functions, the crystal structure of a mutant form of Clusterin was determined. In order to validate the structural data, hydrogen-deuterium exchange kinetics followed by pepsin proteolysis and mass spectrometry analysis of recombinant mutant and wildtype protein were performed (Part 1 of the deposited data). Based on the structure, rational mutants were designed and subjected to functional tests such as chaperone activity, cellular uptake and receptor binding and lipoprotein complex formation. In order to probe the conformation of Clusterin in the lipoprotein complex, free and lipid-bound protein were subjected to limited proteolysis with chymotrypsin and the resultant fragments analyzed by LC/MS proteomics (Part 2 of the deposited data).

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