Mitochondrial ABCG2 regulates the level of ALA-mediated PpIX accumulation in mitochondria of ST-HEK cells.

<p>HEK and ST-HEK cells were incubated for 3 h with ALA in the presence or absence of 1 µM Ko143. After incubation, cells were washed with ALA-free medium and subcellular fractions were isolated as described in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0050082#s2" target="_blank">Materials and Methods</a>. The fluorescence spectrum of each fraction was analyzed by a fluorophotometer. A representative histogram of three independent experiments is shown. The levels of PpIX were shown by black line (No treatment), red line (ALA without Ko143), green line (ALA with Ko143), respectively.