The ethylene signal transduction pathway in Arabidopsis: an emerging paradigm?

In the plant Arabidopsis, ethylene signaling involves at least two putative receptors, both of which resemble the "two-component' regulators known almost exclusively in bacteria. Downstream in the pathway is a putative serine/threonine protein kinase related to the animal Raf protein kinases. This novel combination of signaling proteins has parallels with the postulated osmolarity-response pathway in yeast.