PUBLICATION

The analysis of heterotaxy patients reveals new loss-of-function variants of GRK5

Authors
Lessel, D., Muhammad, T., Casar Tena, T., Moepps, B., Burkhalter, M.D., Hitz, M.P., Toka, O., Rentzsch, A., Schubert, S., Schalinski, A., Bauer, U.M., Kubisch, C., Ware, S.M., Philipp, M.
ID
ZDB-PUB-160914-6
Date
2016
Source
Scientific Reports   6: 33231 (Journal)
Registered Authors
Keywords
Cell signalling, Kinases, Molecular medicine, Organogenesis
MeSH Terms
  • Amino Acid Sequence
  • Animals
  • Embryo, Nonmammalian/embryology
  • Embryo, Nonmammalian/metabolism
  • Female
  • G-Protein-Coupled Receptor Kinase 5/genetics*
  • Gene Frequency
  • Genetic Predisposition to Disease/genetics*
  • HEK293 Cells
  • Heterotaxy Syndrome/genetics*
  • Heterotaxy Syndrome/physiopathology
  • Humans
  • In Situ Hybridization
  • Loss of Function Mutation*
  • Male
  • Polymorphism, Single Nucleotide
  • Sequence Homology, Amino Acid
  • Zebrafish/embryology
  • Zebrafish/genetics
  • Zebrafish Proteins/genetics
PubMed
27618959 Full text @ Sci. Rep.
Abstract
G protein-coupled receptor kinase 5 (GRK5) is a regulator of cardiac performance and a potential therapeutic target in heart failure in the adult. Additionally, we have previously classified GRK5 as a determinant of left-right asymmetry and proper heart development using zebrafish. We thus aimed to identify GRK5 variants of functional significance by analysing 187 individuals with laterality defects (heterotaxy) that were associated with a congenital heart defect (CHD). Using Sanger sequencing we identified two moderately frequent variants in GRK5 with minor allele frequencies <10%, and seven very rare polymorphisms with minor allele frequencies <1%, two of which are novel variants. Given their evolutionarily conserved position in zebrafish, in-depth functional characterisation of four variants (p.Q41L, p.G298S, p.R304C and p.T425M) was performed. We tested the effects of these variants on normal subcellular localisation and the ability to desensitise receptor signalling as well as their ability to correct the left-right asymmetry defect upon Grk5l knockdown in zebrafish. While p.Q41L, p.R304C and p.T425M responded normally in the first two aspects, neither p.Q41L nor p.R304C were capable of rescuing the lateralisation phenotype. The fourth variant, p.G298S was identified as a complete loss-of-function variant in all assays and provides insight into the functions of GRK5.
Genes / Markers
Figures
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Expression
Phenotype
Mutations / Transgenics
Human Disease / Model
Sequence Targeting Reagents
Fish
Antibodies
Orthology
Engineered Foreign Genes
Mapping