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Frontiers in Biology

ISSN 1674-7984

ISSN 1674-7992(Online)

CN 11-5892/Q

Front Biol    2012, Vol. 7 Issue (5) : 477-484    https://doi.org/10.1007/s11515-012-1241-z
RESEARCH ARTICLE
Mutation in angiotensin II type 1 receptor disrupts its binding to angiotensin II leading to hypotension: An insight into hydrogen bonding patterns
Arpita KUNDU, Sudha RAMAIAH, Anand ANBARASU()
Medical & Biological Computing Laboratory, School of Biosciences and Technology, VIT University, Vellore–632014, Tamil Nadu, India
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Abstract

To understand the role of angiotensin II type 1 receptor gene (AGTR1) gene products in relation to hypotension we have analyzed the single nucleotide polymorphisms (SNPs) associated with this gene. This can help us to understand the genetic variations that can alter the function of the gene products. In this present study, we report the polymorphic variant associated with AGTR1 and its weak interaction with angiotensin II (AngII) which leads to hypotension. Out of 1318 SNPs, six are found to be non-synonymous, of which rs1064533 shows significant damaging effect. A missense mutation (T1255G), i.e., from thymine to guanine for rs1064533 in AGTR1 gene results in amino acid substitution from cysteine (Cys) to tryptophan (Trp) in the receptor protein. A strong hydrogen bond exists between Cys289 of native AGTR1 protein and glutamine 167 of AngII. Interestingly, it is replaced by a weak hydrogen bond in the mutant protein between Trp289 (mutant residue) and serine 340. Such a substitution from small, hydrophilic to bulky, hydrophobic residue in AGTR1 protein results in reduced binding affinity of the receptor protein with AngII, leading to hypotension. The results presented from this in silico study will open up new prospect for genetic analysis of AGTR1 gene and will be beneficial to the researchers for understanding the role played by AGTR1 gene in hypotension disease.

Keywords AGTR1      AngII      hypotension      rs1064533      cysteine      tryptophan     
Corresponding Author(s): ANBARASU Anand,Email:aanand@vit.ac.in   
Issue Date: 01 October 2012
 Cite this article:   
Sudha RAMAIAH,Anand ANBARASU,Arpita KUNDU. Mutation in angiotensin II type 1 receptor disrupts its binding to angiotensin II leading to hypotension: An insight into hydrogen bonding patterns[J]. Front Biol, 2012, 7(5): 477-484.
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https://academic.hep.com.cn/fib/EN/10.1007/s11515-012-1241-z
https://academic.hep.com.cn/fib/EN/Y2012/V7/I5/477
SNP IDF-SNPAmino acid change with position
SNP TypeAllele changeFS scoreSIFTPolyPhen
rs1064533Non-synonymousT/G0.743Cys(289)TrpCys(289)Trp
rs12721226Non-synonymousG/A0.374Ala(163)ThrAla(163)Thr
rs12721225Non-synonymousG/T0.566Ala(244)SerAla(244)Ser
rs13095608Non-synonymousT/G0.563Val(41)GlyVal(41)Gly
rs17852013Non-synonymousC/G0.479Leu(222)ValLeu(222)Val
rs17852012Non-synonymousC/A0.400Pro(341)HisPro(341)His
Tab.1  nsSNPs with their corresponding amino acid changes and FS scores
Functional categoryPrediction toolsPrediction results of SNPs
rs1064533FS score: 0.566rs12721226FS score: 0.374rs12721225FS score: 0.566
Protein- codingPolyPhenDamagingBenignDamaging
SIFTDamagingToleratedDamaging
SNP-effectDeleteriousDeleteriousBenign
LS-SNPDeleteriousDeleteriousDeleterious
SNPs3DDeleteriousBenignDeleterious
EnsemblNon-synonymousNon-synonymousNon- synonymous
Splicing regulationESEfinderChangedChangedNot changed
ESRSearchChangedNot changedChanged
PESENot changedNot changedChanged
RESCUE- ESEChangedChangedNot changed
Transcriptional regulationGolden PathExistExistExist
Post-translationOGPETNot existExistExist
ConservedPhastConsConservedConservedConserved
Functional categoryPrediction toolsPrediction results of SNPs
rs13095608FS score: 0.56rs17852013FS score: 0.479rs17852012FS score: 0.400
Protein- codingPolyPhenDamagingDamagingDamaging
SIFTDamagingNot foundNot found
SNP-effectDeleteriousNo entryNo entry
LS-SNPBenignBenignBenign
SNPs3DDeleteriousDeleteriousBenign
EnsemblNon-synonymousNon-synonymousNon-synonymous
Splicing regulationESEfinderNot changedChangedChanged
ESRSearchChangedChangedNot changed
PESENot changedChangedChanged
RESCUE-ESENot changedNot changedNot changed
Transcriptional regulationGolden PathExistExistExist
Post-translationOGPETNot existNot existNot exist
ConservedPhastConsConservedConservedConserved
Tab.2  Functional prediction of nsSNPs by F-SNP database
Fig.1  The native protein structure of AGTR1with Cys (289) and mutant protein structure of AGTR1 with Trp (289) for SNP rs1064533.
Fig.1  The native protein structure of AGTR1with Cys (289) and mutant protein structure of AGTR1 with Trp (289) for SNP rs1064533.
Fig.2  Protein–protein interactions of AGTR1 and AngII. (A) Hydrogen bond with distance of 2.46? between sulfhydryl group at gamma position (SG) of Cys289 in native AGTR1 and oxygen (O) of Gln167 in AngII. Another hydrogen bond with distance of 2.42? between SG of Cys289 in native AGTR1 and nitrogen (N) of Gln167 in AngII. (B) Hydrogen bond with distance of 3.31? between nitrogen at epsilon1 position (NE1) of Trp289 in mutant AGTR1 and hydroxyl group at gamma position (OG) of Ser340 in AngII
Fig.2  Protein–protein interactions of AGTR1 and AngII. (A) Hydrogen bond with distance of 2.46? between sulfhydryl group at gamma position (SG) of Cys289 in native AGTR1 and oxygen (O) of Gln167 in AngII. Another hydrogen bond with distance of 2.42? between SG of Cys289 in native AGTR1 and nitrogen (N) of Gln167 in AngII. (B) Hydrogen bond with distance of 3.31? between nitrogen at epsilon1 position (NE1) of Trp289 in mutant AGTR1 and hydroxyl group at gamma position (OG) of Ser340 in AngII
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