Isolation of CM-EIL genes from melon fruit

Abstract

Two cDNAs encoding ethylene insensitive-3 (EIN3)-like proteins were isolated from mesocarp tissue of ripening melon fruit (CM-EIL1 and CM-EIL2). The predicted amino acid sequences of CM-EIL1 and CM-EIL2 were highly homologous to that of EIN3 (61.4% and 55.1% similarity for CM-EIL1 and CM-EIL2, respectively).
Northern blot analysis showed that the mRNA levels of CM-EIL1 and CM-EIL2 increased in the mesocarp tissue during ripening. Wounding and ethylene treatment did not affect the mRNA levels of CMEIL1 and CM-EIL2 in melon leaf disks.
The CM-EIL proteins had similar transactivation potentials in the yeast system. Transient expression analysis in melon leaf disks showed that CM-EIL1 and CM-EIL2 proteins could activate the transcription of CM-ACO1 by about 3 times for CM-EIL1 and 1.5 times for CM-EIL2, respectively.