ISOLATION AND CHARACTERISATION OF AN ETHYLENE RECEPTOR (ERS-TYPE) FROM OIL PALM (Elaeis guineensis Jacq.) MESOCARP

The oil palm (Elaeis guineensis Jacq.) fruit is climacteric whereby ripening process of the fruits is accompanied by a burst of ethylene production. Hence, to understand the underlying molecular mechanisms and the role of ethylene in the ripening process of oil palm fruits, this study focused on the isolation and characterisation of the ethylene receptor gene, the first component in the ethylene signalling pathway. The full-length cDNA is 2225 kb long and encodes a polypeptide of 629 amino acid residues. Sequence analysis showed it has conserved domains and a protein structure similar to the ERS-type ethylene receptors found in ethylene receptor genes from other plant species. Northern and Southern analyses revealed that it is highly expressed in the mesocarp tissues and that this gene exists as multiple copies in the oil palm genome. These results provide evidence that oil palm fruit development is regulated by ethylene through the action of the EGER D3 ethylene receptor gene, which opens up the possibility of manipulating the ethylene receptor to control ethylene sensitivity during oil palm fruit development to help further improve oil palm yields.