Cloning and characterization of ethylene-insensitive 2 (EIN2) gene from Cucumis melo

Melon is an ideal alternative model fruit to examine ethylene perception and sensitivity. Ethylene insensitive 2 (EIN2), an integral membrane protein in the endoplasmic reticulum, is an important regulator of ethylene and other phytohormone signaling. We isolated for the first time a cDNA clone that encoded EIN2 homolog on the basis of melon (Cucumis melo L. cv. Hetao) fruit total RNA by in silico cloning and reverse-transcription PCR (RT-PCR). The cDNA contained an open reading frame of 3876 bp corresponding to a polypeptide of 1291 amino acids with a predicted mol wt of 141 kD. The expression patterns of different developmental stages of fruit, vegetative organs, and reproductive tissues and upon the treatment with IAA and ABA were analyzed. CmEIN2 mediates ethylene signals in many processes and is a component of signal transduction by ethylene, auxin, and abscisic acid.