Characterisation of cyclic neuroprotective PDZ binding ligands. / AlNasir, Jamal; Austen, Brian.

2011. Poster session presented at Royal Society of Chemistry (RSC): Protein and Peptide Science Group Early Stage Researcher Meeting, London, United Kingdom.

Research output: Contribution to conferencePosterpeer-review

Published

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Characterisation of cyclic neuroprotective PDZ binding ligands. / AlNasir, Jamal; Austen, Brian.

2011. Poster session presented at Royal Society of Chemistry (RSC): Protein and Peptide Science Group Early Stage Researcher Meeting, London, United Kingdom.

Research output: Contribution to conferencePosterpeer-review

Harvard

AlNasir, J & Austen, B 2011, 'Characterisation of cyclic neuroprotective PDZ binding ligands', Royal Society of Chemistry (RSC): Protein and Peptide Science Group Early Stage Researcher Meeting, London, United Kingdom, 8/11/11 - 8/11/11.

APA

AlNasir, J., & Austen, B. (2011). Characterisation of cyclic neuroprotective PDZ binding ligands. Poster session presented at Royal Society of Chemistry (RSC): Protein and Peptide Science Group Early Stage Researcher Meeting, London, United Kingdom.

Vancouver

AlNasir J, Austen B. Characterisation of cyclic neuroprotective PDZ binding ligands. 2011. Poster session presented at Royal Society of Chemistry (RSC): Protein and Peptide Science Group Early Stage Researcher Meeting, London, United Kingdom.

Author

AlNasir, Jamal ; Austen, Brian. / Characterisation of cyclic neuroprotective PDZ binding ligands. Poster session presented at Royal Society of Chemistry (RSC): Protein and Peptide Science Group Early Stage Researcher Meeting, London, United Kingdom.

BibTeX

@conference{2d49009b20df4eda9813109b370a2425,
title = "Characterisation of cyclic neuroprotective PDZ binding ligands",
abstract = "Neurodegenerative diseases feature neurochemical and neuropathological changes which are intimately linked with excitotoxicity. PSD-95 a post-synaptic scaffold protein of the NMDA receptor complex, containing PDZ domains coupling to a PMCa2B calcium channel, NMDAR2, and i-nos, has been found to mediate Glutamate induced excitotoxicity. Neuronal damage may be mediated by calcium intrusion and oxidative stress and PSD-95 is a potential therapeutic target. PDZ binding ligands have been designed based on the C-terminal sequence of the PMCa2b calcium channel sub-unit in order to disrupt its interaction with PSD95 via PDZ domain 1. Current PDZ binding ligands currently have Kd constants in the micromolar range and tighter binding is required (Kd constants in nanomolar range) for therapeutic use. Structural alterations have been proposed by various researchers to this end including cyclisation of PDZ peptide ligands. Putative PDZ binding ligands were modeled in Silico based on existing structures but with important refinements to improve binding affinity. Ligand-Protein docking simulations were performed in order to select a group of ligands to synthesise. Solid Phase peptide synthesis was employed following the Fmoc protocol. Cyclisation was via amide formation between orthogonally protected side-chains. The PDZ binding peptides produced were tested in vitro on SHSY-5Y neuroblastoma cell lines in the presence of 2mmol Glutamate, and insult and cell viability quantified via MTT assay. The results indicate that the modification of a linker residue and side-chain on the PDZ ligand improves efficacy as seen by protection against excitotoxic cell death. Immunohistochemical studies of biotinylated PDZ peptides and their PSD-95 target demonstrated co-localisation and cell protection for an asparaginyl bridged peptide compared to a glutamate -bridged peptide. Our results also show that cyclisation alone does not confer improvement in PDZ binding affinity contrary to what has been postulated by other researchers.",
keywords = "RSC, cyclic, neuroprotective, pdz, binding, ligands, PSD-95, NMDA , SHSY-5Y, Alzheimers, excitotoxicity, excitotoxic, in Silico, molecular docking, synthesis, peptide synthesis, PMCA-2b, glutatamate insult, FMOC peptide synthesis, MTT assay, immunohistochemistry",
author = "Jamal AlNasir and Brian Austen",
year = "2011",
month = feb,
day = "8",
language = "English",
note = "Royal Society of Chemistry (RSC): Protein and Peptide Science Group Early Stage Researcher Meeting ; Conference date: 08-11-2011 Through 08-11-2011",

}

RIS

TY - CONF

T1 - Characterisation of cyclic neuroprotective PDZ binding ligands

AU - AlNasir, Jamal

AU - Austen, Brian

PY - 2011/2/8

Y1 - 2011/2/8

N2 - Neurodegenerative diseases feature neurochemical and neuropathological changes which are intimately linked with excitotoxicity. PSD-95 a post-synaptic scaffold protein of the NMDA receptor complex, containing PDZ domains coupling to a PMCa2B calcium channel, NMDAR2, and i-nos, has been found to mediate Glutamate induced excitotoxicity. Neuronal damage may be mediated by calcium intrusion and oxidative stress and PSD-95 is a potential therapeutic target. PDZ binding ligands have been designed based on the C-terminal sequence of the PMCa2b calcium channel sub-unit in order to disrupt its interaction with PSD95 via PDZ domain 1. Current PDZ binding ligands currently have Kd constants in the micromolar range and tighter binding is required (Kd constants in nanomolar range) for therapeutic use. Structural alterations have been proposed by various researchers to this end including cyclisation of PDZ peptide ligands. Putative PDZ binding ligands were modeled in Silico based on existing structures but with important refinements to improve binding affinity. Ligand-Protein docking simulations were performed in order to select a group of ligands to synthesise. Solid Phase peptide synthesis was employed following the Fmoc protocol. Cyclisation was via amide formation between orthogonally protected side-chains. The PDZ binding peptides produced were tested in vitro on SHSY-5Y neuroblastoma cell lines in the presence of 2mmol Glutamate, and insult and cell viability quantified via MTT assay. The results indicate that the modification of a linker residue and side-chain on the PDZ ligand improves efficacy as seen by protection against excitotoxic cell death. Immunohistochemical studies of biotinylated PDZ peptides and their PSD-95 target demonstrated co-localisation and cell protection for an asparaginyl bridged peptide compared to a glutamate -bridged peptide. Our results also show that cyclisation alone does not confer improvement in PDZ binding affinity contrary to what has been postulated by other researchers.

AB - Neurodegenerative diseases feature neurochemical and neuropathological changes which are intimately linked with excitotoxicity. PSD-95 a post-synaptic scaffold protein of the NMDA receptor complex, containing PDZ domains coupling to a PMCa2B calcium channel, NMDAR2, and i-nos, has been found to mediate Glutamate induced excitotoxicity. Neuronal damage may be mediated by calcium intrusion and oxidative stress and PSD-95 is a potential therapeutic target. PDZ binding ligands have been designed based on the C-terminal sequence of the PMCa2b calcium channel sub-unit in order to disrupt its interaction with PSD95 via PDZ domain 1. Current PDZ binding ligands currently have Kd constants in the micromolar range and tighter binding is required (Kd constants in nanomolar range) for therapeutic use. Structural alterations have been proposed by various researchers to this end including cyclisation of PDZ peptide ligands. Putative PDZ binding ligands were modeled in Silico based on existing structures but with important refinements to improve binding affinity. Ligand-Protein docking simulations were performed in order to select a group of ligands to synthesise. Solid Phase peptide synthesis was employed following the Fmoc protocol. Cyclisation was via amide formation between orthogonally protected side-chains. The PDZ binding peptides produced were tested in vitro on SHSY-5Y neuroblastoma cell lines in the presence of 2mmol Glutamate, and insult and cell viability quantified via MTT assay. The results indicate that the modification of a linker residue and side-chain on the PDZ ligand improves efficacy as seen by protection against excitotoxic cell death. Immunohistochemical studies of biotinylated PDZ peptides and their PSD-95 target demonstrated co-localisation and cell protection for an asparaginyl bridged peptide compared to a glutamate -bridged peptide. Our results also show that cyclisation alone does not confer improvement in PDZ binding affinity contrary to what has been postulated by other researchers.

KW - RSC

KW - cyclic

KW - neuroprotective

KW - pdz

KW - binding

KW - ligands

KW - PSD-95

KW - NMDA

KW - SHSY-5Y

KW - Alzheimers

KW - excitotoxicity

KW - excitotoxic

KW - in Silico

KW - molecular docking

KW - synthesis

KW - peptide synthesis

KW - PMCA-2b

KW - glutatamate insult

KW - FMOC peptide synthesis

KW - MTT assay

KW - immunohistochemistry

M3 - Poster

T2 - Royal Society of Chemistry (RSC): Protein and Peptide Science Group Early Stage Researcher Meeting

Y2 - 8 November 2011 through 8 November 2011

ER -