Identification of a novel Arg→Cys mutation in the LDL receptor that contributes to spontaneous hypercholesterolemia in pigs

We previously carried out genetic and metabolic studies in a partially inbred herd of pigs carrying cholesterol-elevating mutations. Quantitative pedigree analysis indicated that apolipoprotein (apo)B and a second major gene were responsible for the hypercholesterolemia in these animals. In this stu...

Full description

Bibliographic Details
Main Authors: Kurt A.A. Grunwald, Kathryn Schueler, Patricia J. Uelmen, Beth A. Lipton, Mary Kaiser, Kimberly Buhman, Alan D. Attie
Format: Article
Language:English
Published: Elsevier 1999-03-01
Series:Journal of Lipid Research
Subjects:
Online Access:http://www.sciencedirect.com/science/article/pii/S0022227520324524
_version_ 1818899142085181440
author Kurt A.A. Grunwald
Kathryn Schueler
Patricia J. Uelmen
Beth A. Lipton
Mary Kaiser
Kimberly Buhman
Alan D. Attie
author_facet Kurt A.A. Grunwald
Kathryn Schueler
Patricia J. Uelmen
Beth A. Lipton
Mary Kaiser
Kimberly Buhman
Alan D. Attie
author_sort Kurt A.A. Grunwald
collection DOAJ
description We previously carried out genetic and metabolic studies in a partially inbred herd of pigs carrying cholesterol-elevating mutations. Quantitative pedigree analysis indicated that apolipoprotein (apo)B and a second major gene were responsible for the hypercholesterolemia in these animals. In this study, we assessed LDL receptor function by three different methods: ligand blots of liver membranes using β-very low density lipoprotein (VLDL) as a ligand; low density lipoprotein (LDL)-dependent proliferation of T-lymphocytes; and direct binding of 125I-labeled LDL to cultured skin fibroblasts. All three methods demonstrated that LDL receptor ligands bound with decreased affinity to the LDL receptor in these animals. In skin fibroblasts from the hypercholesterolemic pigs, the Kd of binding was about 4-fold higher than in cells from normal pigs. The cDNA of the pig LDL receptor from normal and hypercholesterolemic pigs was isolated and sequenced. We identified a missense mutation that results in an Arg→Cys substitution at the position corresponding to Arg94 of the human LDL receptor. The mutation is in the third repeat of the ligand binding domain of the receptor. By single-stranded conformational polymorphism (SSCP) analysis, we studied the relationship between LDL receptor genotype and plasma cholesterol phenotype. In contrast to humans, the hypercholesterolemia associated with the LDL receptor mutation in pigs was expressed as a recessive trait. The LDL receptor mutation made a far more significant contribution to hypercholesterolemia than did the apoB mutation, consistent with observations made in human subjects with apoB mutations. Within each genotypic group (mutated apoB or mutated receptor), there was a wide range in plasma cholesterol. As the animals were on a well-controlled low-fat diet, this suggests that there are additional genetic factors that influence the penetrance of cholesterol-elevating mutations. —Grunwald, K. A. A., K. Schueler, P. J. Uelmen, B. A. Lipton, M. Kaiser, K. Buhman, and A. D. Attie. Identification of a novel Arg→Cys mutation in the LDL receptor that contributes to spontaneous hypercholesterolemia in pigs. J. Lipid Res. 1999. 40: 475–485.
first_indexed 2024-12-19T19:43:15Z
format Article
id doaj.art-28895ec64dc943c7bb7e71a4c1d01161
institution Directory Open Access Journal
issn 0022-2275
language English
last_indexed 2024-12-19T19:43:15Z
publishDate 1999-03-01
publisher Elsevier
record_format Article
series Journal of Lipid Research
spelling doaj.art-28895ec64dc943c7bb7e71a4c1d011612022-12-21T20:08:12ZengElsevierJournal of Lipid Research0022-22751999-03-01403475485Identification of a novel Arg→Cys mutation in the LDL receptor that contributes to spontaneous hypercholesterolemia in pigsKurt A.A. Grunwald0Kathryn Schueler1Patricia J. Uelmen2Beth A. Lipton3Mary Kaiser4Kimberly Buhman5Alan D. Attie6Departments of Biochemistry and Comparative Biosciences, University of Wisconsin-Madison, Madison, WI 53706Departments of Biochemistry and Comparative Biosciences, University of Wisconsin-Madison, Madison, WI 53706Departments of Biochemistry and Comparative Biosciences, University of Wisconsin-Madison, Madison, WI 53706Departments of Biochemistry and Comparative Biosciences, University of Wisconsin-Madison, Madison, WI 53706Departments of Biochemistry and Comparative Biosciences, University of Wisconsin-Madison, Madison, WI 53706Departments of Biochemistry and Comparative Biosciences, University of Wisconsin-Madison, Madison, WI 53706To whom correspondence should be addressed.; Departments of Biochemistry and Comparative Biosciences, University of Wisconsin-Madison, Madison, WI 53706We previously carried out genetic and metabolic studies in a partially inbred herd of pigs carrying cholesterol-elevating mutations. Quantitative pedigree analysis indicated that apolipoprotein (apo)B and a second major gene were responsible for the hypercholesterolemia in these animals. In this study, we assessed LDL receptor function by three different methods: ligand blots of liver membranes using β-very low density lipoprotein (VLDL) as a ligand; low density lipoprotein (LDL)-dependent proliferation of T-lymphocytes; and direct binding of 125I-labeled LDL to cultured skin fibroblasts. All three methods demonstrated that LDL receptor ligands bound with decreased affinity to the LDL receptor in these animals. In skin fibroblasts from the hypercholesterolemic pigs, the Kd of binding was about 4-fold higher than in cells from normal pigs. The cDNA of the pig LDL receptor from normal and hypercholesterolemic pigs was isolated and sequenced. We identified a missense mutation that results in an Arg→Cys substitution at the position corresponding to Arg94 of the human LDL receptor. The mutation is in the third repeat of the ligand binding domain of the receptor. By single-stranded conformational polymorphism (SSCP) analysis, we studied the relationship between LDL receptor genotype and plasma cholesterol phenotype. In contrast to humans, the hypercholesterolemia associated with the LDL receptor mutation in pigs was expressed as a recessive trait. The LDL receptor mutation made a far more significant contribution to hypercholesterolemia than did the apoB mutation, consistent with observations made in human subjects with apoB mutations. Within each genotypic group (mutated apoB or mutated receptor), there was a wide range in plasma cholesterol. As the animals were on a well-controlled low-fat diet, this suggests that there are additional genetic factors that influence the penetrance of cholesterol-elevating mutations. —Grunwald, K. A. A., K. Schueler, P. J. Uelmen, B. A. Lipton, M. Kaiser, K. Buhman, and A. D. Attie. Identification of a novel Arg→Cys mutation in the LDL receptor that contributes to spontaneous hypercholesterolemia in pigs. J. Lipid Res. 1999. 40: 475–485.http://www.sciencedirect.com/science/article/pii/S0022227520324524cholesterolapolipoprotein BpolymorphismsLDL receptorpigshypercholesterolemia
spellingShingle Kurt A.A. Grunwald
Kathryn Schueler
Patricia J. Uelmen
Beth A. Lipton
Mary Kaiser
Kimberly Buhman
Alan D. Attie
Identification of a novel Arg→Cys mutation in the LDL receptor that contributes to spontaneous hypercholesterolemia in pigs
Journal of Lipid Research
cholesterol
apolipoprotein B
polymorphisms
LDL receptor
pigs
hypercholesterolemia
title Identification of a novel Arg→Cys mutation in the LDL receptor that contributes to spontaneous hypercholesterolemia in pigs
title_full Identification of a novel Arg→Cys mutation in the LDL receptor that contributes to spontaneous hypercholesterolemia in pigs
title_fullStr Identification of a novel Arg→Cys mutation in the LDL receptor that contributes to spontaneous hypercholesterolemia in pigs
title_full_unstemmed Identification of a novel Arg→Cys mutation in the LDL receptor that contributes to spontaneous hypercholesterolemia in pigs
title_short Identification of a novel Arg→Cys mutation in the LDL receptor that contributes to spontaneous hypercholesterolemia in pigs
title_sort identification of a novel arg cys mutation in the ldl receptor that contributes to spontaneous hypercholesterolemia in pigs
topic cholesterol
apolipoprotein B
polymorphisms
LDL receptor
pigs
hypercholesterolemia
url http://www.sciencedirect.com/science/article/pii/S0022227520324524
work_keys_str_mv AT kurtaagrunwald identificationofanovelargcysmutationintheldlreceptorthatcontributestospontaneoushypercholesterolemiainpigs
AT kathrynschueler identificationofanovelargcysmutationintheldlreceptorthatcontributestospontaneoushypercholesterolemiainpigs
AT patriciajuelmen identificationofanovelargcysmutationintheldlreceptorthatcontributestospontaneoushypercholesterolemiainpigs
AT bethalipton identificationofanovelargcysmutationintheldlreceptorthatcontributestospontaneoushypercholesterolemiainpigs
AT marykaiser identificationofanovelargcysmutationintheldlreceptorthatcontributestospontaneoushypercholesterolemiainpigs
AT kimberlybuhman identificationofanovelargcysmutationintheldlreceptorthatcontributestospontaneoushypercholesterolemiainpigs
AT alandattie identificationofanovelargcysmutationintheldlreceptorthatcontributestospontaneoushypercholesterolemiainpigs