Carbohydrate deprivation upsurges the expression of genes responsible for programmed cell death in inflorescence tissues of oil palm (Elaeis guineensis Jacq.)

The aim of this present study was to analyze global gene expression from a developing inflorescence of oil palm under complete defoliation stress. We used the Illumina platform to sequence six cDNA libraries of defoliated and nondefoliated tissues. The frequency of differentially expressed genes (DEGs) decreased with increasing fold change at P ≤ 0.05. Gene ontology analysis revealed that about 15% of all DEGs were responsible for stress response while 13.9% of genes were responsible for cell organization and developmental processes. DAVID functional analysis clustering of DEGs identified a higher enrichment score (ES) for cellular response to stress (ES = 3.2%), response to abiotic stress (ES = 3.12%), cell cycle (ES = 2.25%), and response to carbohydrate stimulus (ES = 1.34%), signifying the functional implications of these processes in carbohydrate depletion and flower development. The top ten DEGs were principally responsible for stress response and cell death. There was a high expression of the SEC14, TIFY8, NUDT7, and DUF538 genes that are related to cell death. It is necessary to further investigate the role of these genes in premature inflorescence abortion in oil palm during stress.