Isoprene Acts as a Signaling Molecule in Gene Networks Important for Stress Responses and Plant Growth.

Isoprene synthase converts dimethylallyl diphosphate to isoprene and appears to be necessary and sufficient to allow plants to emit isoprene at significant rates. Isoprene can protect plants from abiotic stress but is not produced naturally by all plants; for example, Arabidopsis () and tobacco () do not produce isoprene. It is typically present at very low concentrations, suggesting a role as a signaling molecule; however, its exact physiological role and mechanism of action are not fully understood.