Beyond oxidative stress: Tetrakis (4-hydroxyphenyl) porphyrin induces non-canonical programmed cell death in Tobacco BY-2 cells.

Tetrakis (4-hydroxyphenyl) porphyrin (THPP) causes significant dark toxicity and induces non-canonical programmed cell death in Tobacco BY-2 cells, involving autophagy.

• Why it matters: Understanding dark toxicity of photosensitizers like THPP is crucial because their effects in plants are largely unexplored, impacting biological processes and potential applications in agriculture or medicine.
• What they did: The study examined THPP’s stability, cellular localization, and effects on cell viability, mitochondrial function, and autophagy in TBY-2 cells using confocal imaging and biochemical assays, with THPP at 10 μM.
• The result: THPP’s toxicity involves autophagy rather than canonical programmed cell death, and inhibiting autophagy significantly reduces cell death, revealing a novel pathway for plant cell demise.