The Effect of Protein Import on Membrane Potential

Author

Ruth Hartke, CUNY Bernard M Baruch CollegeFollow

Date of Award

Fall 2016

Document Type

Thesis

Degree Name

Bachelor of Arts (BA)

Honors Designation

yes

Program of Study

Biology

Language

English

First Advisor

Peixoto, Pablo M.

Abstract

Mitochondria are essential organelles often referred to as the “power plants” of eukaryotic cells. Energy conversion in mitochondria relies on oxidation of metabolite intermediates by protein components of the electron transport chain and establishment of an electrochemical gradient across the inner membrane. Some of the proteins involved are encoded by mitochondrial DNA, but the vast majority, over 98%, has to be imported from the cytosol. Protein import complexes form pores in the outer and inner membranes to mediate the process. However, opening of these pores would in theory jeopardize formation of the electrochemical gradient. In this study we examined this possibility by measuring membrane potential of yeast mitochondria during protein import using spectrofluorimetry and fluorescence microscopy. Contrary to expectation, our results suggest that treatment with import peptides hyperpolarize mitochondria, provided that the import pores are expressed. If confirmed in other experimental models, these results may help determine a potential preventive mechanism that allows the co-existence of protein import and an electrochemical gradient across the inner membrane.

Recommended Citation

Hartke, Ruth, "The Effect of Protein Import on Membrane Potential" (2016). CUNY Academic Works.
https://academicworks.cuny.edu/bb_etds/73