About the event
Presenter: Esther Dodson
Host: Phil Garner
Title: Ligand-Directed Affinity Labeling of Protein Conjugates
Abstract: Proteins can be covalently conjugated with small-molecule labels to achieve a variety of functions. For example, proteins can be labelled with drug molecules to target specific cells for disease therapies, or a radioactive or fluorescent label can be used to detect proteins in a Western blot. Nucleophilic substitution is a common method to covalently bond a protein to a “payload” molecule. Generally, substitution reactions have poor site-selectivity and are unable to label specific proteins in complex matrices. In addition, many nucleophilic moieties are too reactive to effectively label target proteins in living systems. Ligand-directed affinity (LDA) chemistry addresses these complications by attaching a protein-specific ligand to the probe molecule. The protein can then strongly bind the ligand-containing probe increasing the probability that a nearby nucleophilic residue will react with the probe’s electrophilic moiety. LDA probes are inherently protein- and site-specific due to the nature of the protein-ligand binding interaction, and many of these probes can label target proteins in vivo. In a paper by Hamachi et al. (2013) a fluorescent label was covalently attached to an FK506-binding protein (FKBP12) by using a ligand-directed probe containing a tosylate-derived reactive moiety. Introducing the labeled protein to living cells allowed for the in vivo FRET imaging of the rapamycin-mediated interaction between FKBP12 and the FKBP-rapamycin binding (FRB) domain of mTOR.
Zoom Invite Information:
Scheduled: 1 to 2:30 p.m.
Join from PC, Mac, Linux, iOS, or Android: https://wsu.zoom.us/j/8200631218
Meeting ID: 820 063 1218