Skip to main content

Research Repository

Advanced Search

The effect of single nucleotide polymorphisms and metabolic substrates on the cellular distribution of mammalian BK channels.

Adeyileka-Tracz, Bernadette Ayokunumi

Authors

Bernadette Ayokunumi Adeyileka-Tracz



Contributors

Iain Rowe
Supervisor

Stuart F. Cruickshank
Supervisor

Helene Widmer
Supervisor

Abstract

Humans are approximately 99% similar with inter-individual differences caused in part by single-nucleotide polymorphisms (SNPs), which poses a challenge for the effective treatment of disease. Bioinformatics resources can help to store and analyse gene and protein information to address this challenge, however these resources have limitations, so the collation and biocuration of gene and protein information is required. Using the large conductance calcium- and voltage-activated potassium channel, also known as the Big Potassium (BK) channel as an example, due to its ubiquitous expression and widespread varied role in human physiology, this study aimed to prioritise SNPs with the potential to affect the function of the channel. Using a BK channel resource created with bioinformatics tools and published literature, mSlo SNPs H55Q and G57A, located in the S0-S1 linker, were prioritised and selected for lab-based verification. These SNPs flank three cysteine residues proven to modulate channel cellular distribution via palmitoylation, a reversible process shown to increase protein association with the cell membrane. The SNPs alter the predicted palmitoylation status of C56, one of the cysteine residues located in the S0-S1 linker. The cellular distribution of BK channels incorporating the SNPs was assessed using confocal microscopy and revealed that the direction and magnitude of SNP mimetic cell membrane expression was closely related to the C56 predicted palmitoylation score; a 'C56 palmitoylation pattern' was observed. It was shown that exposure to metabolic substrates glucose, palmitate and oleate modulated SNP-mimetic cellular distribution and could invert the 'C56 palmitoylation pattern', indicating that there is interplay between the metabolic status of the cell and the amino-acid composition of the channel via palmitoylation. The creation of a novel BK channel resource in this thesis highlighted the limitations, and inter-dependency of bioinformatics and lab based experimentation, whilst SNP verification experiments solidified the link between S0-S1 cysteine residues and BK cellular distribution. BK channel function is linked with a number of physiological processes; thus, the potential clinical consequences of the SNPs prioritised in this thesis require further research.

Citation

ADEYILEKA-TRACZ, B.A. 2017. The effect of single nucleotide polymorphisms and metabolic substrates on the cellular distribution of mammalian BK channels. Robert Gordon University, PhD thesis.

Thesis Type Thesis
Deposit Date Feb 2, 2018
Publicly Available Date Feb 2, 2018
Keywords SNPs; BK channel; Cell membrane expression; Palmitoylation; Glucose; Palmitate; Oleate; Biocuration; Cysteine; Bioinformatics
Public URL http://hdl.handle.net/10059/2713
Contract Date Feb 2, 2018
Award Date Sep 30, 2017

Files




You might also like



Downloadable Citations