The coordinated role of ethylene and glucose in sulfur-mediated protection of photosynthetic inhibition by cadmium.

Ethylene controls photosynthesis and induces tolerance of plants to metal stress. However, little is known about the interaction between ethylene, photosynthesis and sulfur (S) availability under cadmium (Cd) stress. Recently, we reported that ethylene controls photosynthesis by increasing glutathione (GSH) synthesis with sufficient-S availability under Cd stress. Plants treated with Cd were less sensitive to ethylene and showed photosynthetic inhibition. Ethylene sensitivity of plants was increased with exogenously-sourced ethylene or with sufficient-S application resulting in induced GSH synthesis and alleviation of photosynthetic inhibition by Cd. In this addendum we present some additional data indicating that ethylene regulates photosynthesis by reducing glucose (Glc) sensitivity, thus reducing the Glc-mediated photosynthetic repression.