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Purification and Aggregation of the Amyloid Precursor Protein Intracellular Domain
10:08

Purification and Aggregation of the Amyloid Precursor Protein Intracellular Domain

Published on: August 28, 2012

Hepatic amyloidosis resulting from deposition of the apolipoprotein A-I variant Leu75Pro

Daniel Coriu1, Angela Dispenzieri, Fred J Stevens

  • 1University of Medicine Carol Davila, Bucharest, Romania.

Amyloid : the International Journal of Experimental and Clinical Investigation : the Official Journal of the International Society of Amyloidosis
|February 28, 2004
PubMed

Insights

Apolipoprotein A-I amyloidosis (AApo A-I) is a genetic disorder. A specific mutation, Leu75Pro, causes liver amyloid deposits and affects diverse ethnicities.

Area of Science:

  • Genetics
  • Biochemistry
  • Pathology

Background:

  • Apolipoprotein A-I amyloidosis (AApo A-I) is an inherited systemic disease.
  • It is caused by the deposition of Apo A-I-related protein fibrils in tissues.
  • Nine genetic variants of the Apo A-I gene have been previously identified.

Observation:

  • A tenth variant, Leu75Pro, was recently identified in an Italian population, linked to liver amyloidosis.
  • This study investigates a patient of a different ethnicity with hepatic amyloidosis and the Leu75Pro mutation.
  • Genomic DNA analysis confirmed the presence of the mutation in the Apo A-I gene.

Findings:

  • Fibrils isolated from the patient's liver were primarily composed of an N-terminal Apo A-I fragment (approx. 96 residues) with the Leu75Pro substitution.
  • The patient was heterozygous for the mutation.
  • Less than 10% of plasma Apo A-I contained the aberrant protein; the rest was wild-type.

Implications:

  • The Leu75Pro variant is associated with a predominant hepatic phenotype.
  • This mutation can occur in individuals from diverse ethnic backgrounds.
  • Further research into AApo A-I pathogenesis and genetic variations is warranted.

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