ISOLATION AND CHARACTERIZATION OF AN ETHYLENE RECEPTOR HOMOLOG GENE, CM-ETR2, FROM MELON FRUIT

Ethylene is perceived by a family of membrane localized receptors that are homologous to bacterial two component histidine kinases. The ethylene receptor multigene family can be divided into subfamily 1 and 2. The Cm-ERS1 and Cm-ETR1 which belong to the subfamily 1 in melon have already been isolated and characterized (Sato-Nara et al., 1999; Takahashi et al., 2002; Ma et al., in submission). In order to gain better understanding of the role that ethylene receptor subfamilies play in melon fruit development and ripening, we isolated the full-length sequence of Cm-ETR2, a subfamily 2 receptor homolog from melon (Cucumis melo L. cv. Vedrantais) fruit, using PCR-based technology. We report the characteristics and the gene expression patterns of this receptor homolog during melon fruit development and ripening and discuss the possible role of subfamily 2 receptors in melon fruit development.