text: The mycotoxin phomoxanthone A, or PXA for short, is a toxic natural product that affects the mitochondria. It is the most toxic and the best studied of the naturally occurring phomoxanthones. PXA has recently been shown to induce rapid, non-canonical mitochondrial fission by causing the mitochondrial matrix to fragment while the outer mitochondrial membrane can remain intact. This process was shown to be independent from the mitochondrial fission and fusion regulators DRP1 and OPA1.