The ethylene-response pathway: signal perception to gene regulation.

Tremendous strides have been made in the past year toward elucidating the ethylene-response pathway. Ethylene is perceived by a family of histidine kinase-like receptors, which negatively regulate ethylene responses. Binding of ethylene requires a copper cofactor, and proper receptor function relies on a copper transporter. Downstream, EIN2 is a structurally novel protein containing an integral membrane domain. In the nucleus, the EIN3 family of DNA-binding proteins regulates transcription in response to ethylene, and an immediate target of EIN3 is a DNA-binding protein of the AP2/EREBP family.