Photoactivation of mt-PAGFP.

<p>Simultaneous recording of TMRE (a1) and mt-PAGFP (a2) images. Before photoactivation, there is no GFP fluorescence of mt-PAGFP detected in <b>a2</b>. A small area (~ 10 X 10 µm<sup>2</sup>) of the fiber was photoactivated by a 364 nm laser (<b>b</b>). After photoactivation, the fiber was imaged again simultaneously for both TMRE (c1) and mt-PAGFP (c2) at the fiber region including the area with photoactivated GFP. Note the visible GFP fluorescence of mt-PAGFP in <b>c2</b> recorded at the same laser intensity as in <b>a2</b>. </p>