PhD Topics

1. Ratiometric genetically encoded fluorescent sensors for measurement of intracellular pH values

Supervisor: Dmitriy Chudakov, Ph.D., DSc.

Annotation:

Intracellular pH influences a lot of processes in cellular cytoplasm and intracellular compartments. [1-10]. Fluorescent proteins have many advantages compared to chemical fluorescent dyes in living cell imaging, including less invasive measurement and possibility of tethering the reporter to any cellular organelle or compartment. Sensitivity to pH has been used to develop genetically engineer encodable pH indicators [11]. Genetically encoded fluorescent pH reporters enable to measure spatial and temporal changes of pH in dynamics. To date, in spite of development of different geneticaly encoded fluorescent-based pH indicators, both single-color and ratiometric pH sensors have been ultimately used rather to detect the direction of pH changes, than to measure exact pH value in live cell microscopy. The project will be dedicated to creation of ratiometric pH sensors based on pH-sensitive GFP mutants and highly pH-independent red fluorescent protein which can be used for precise imaging of pH value for a great variety of biological events and signals.

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