2. Academic Validation
  3. Analysis of genetic polymorphism and biochemical characterization of a functionally decreased variant in prostacyclin synthase gene (CYP8A1) in humans

Analysis of genetic polymorphism and biochemical characterization of a functionally decreased variant in prostacyclin synthase gene (CYP8A1) in humans

  • Arch Biochem Biophys. 2015 Mar 1;569:10-8. doi: 10.1016/j.abb.2015.01.012.
Sun-Ah Cho 1,  Katie Jo Rohn-Glowacki 2,  Yazun B Jarrar 1,  Myeongjin Yi 1,  Woo-Young Kim 1,  Jae-Gook Shin 3,  Su-Jun Lee 4
Affiliations

Affiliations

  • 1 Department of Pharmacology, Pharmacogenomics Research Center, Inje University College of Medicine, Inje University, Busan 614-735, South Korea.
  • 2 Department of Pharmacology and Toxicology, University of Alabama at Birmingham, Birmingham, AL, USA.
  • 3 Department of Pharmacology, Pharmacogenomics Research Center, Inje University College of Medicine, Inje University, Busan 614-735, South Korea; Department of Clinical Pharmacology, Inje University College of Medicine, Inje University Busan Paik Hospital, Busan 614-735, South Korea. Electronic address: phshinjg@gmail.com.
  • 4 Department of Pharmacology, Pharmacogenomics Research Center, Inje University College of Medicine, Inje University, Busan 614-735, South Korea. Electronic address: 2sujun@inje.ac.kr.
PMID: 25623425 DOI: 10.1016/j.abb.2015.01.012
Abstract

Prostacyclin synthase (CYP8A1) is an Enzyme responsible for the biosynthesis of prostacyclin (PGI2) which inhibits platelet activation and exhibits anti-inflammatory effect. The objectives of this study were to identify CYP8A1 genetic variants and characterize functional consequences of CYP8A1 variants. In total, 27 variants including four previously unidentified single-nucleotide polymorphisms (SNPs) were identified by direct DNA Sequencing in Koreans (n=48). Among them, CYP8A1 A447T and E314Stop were newly assigned as CYP8A1(∗)5 and CYP8A1(∗)6 by the Human Cytochrome P450 Allele Nomenclature Committee, respectively. CYP8A1(∗)5 was found in the heme binding area in three individuals as a heterozygous mutation. To investigate the functional change of CYP8A1(∗)5, CYP8A1(∗)5 and wild-type CYP8A1 protein were overexpressed in an Escherichia coli expression system and purified. Metabolism of PGH2 by the CYP8A1(∗)5 protein exhibited significantly decreased activity, resulting in a 45% decrease in Vmax and a 1.8-fold decrease in intrinsic clearance compared to the wild-type. Based on the predicted crystal structure of CYP8A1(∗)5 using the Molecular Operating Environment platform, the distance from CYP8A1 Cys441 to the heme was altered with a significantly changed binding free energy for the mutant protein. Further studies would be needed to determine the effect of CYP8A1(∗)5 on PGI2 levels in humans.

Keywords

CYP8A1; Cytochrome P450; Polymorphism; Prostacyclin; SNP.

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