Genome-wide analysis of gene expression in Lobosphaera incisa under nitrogen starvation and different light intensities

Lobosphaera incisa is an oleaginous green microalga and a target organism of high biotechnological interest because it is the richest known plant source of arachidonic acid (ARA), a pharmaceutically and nutraceutically valuable omega-6 long-chain polyunsaturated fatty acid. ARA is deposited in considerable amounts in storage lipid triacylglycerols, most profoundly when L. incisa is exposed to nitrogen starvation. To get insights into genome-wide gene expression in L. incisa under nitrogen starvation, the whole transcriptome was sequenced by RNA-Seq. Total RNA was isolated under four growth conditions: exponential growth (control) and growth in nitrogen-depleted medium for 12 or 72 hours at normal or high light intensities. Statistical and differential gene expression analyses were conducted by comparing the various samples. The results of this study were used to identify patterns of gene regulation with special emphasis on genes involved in fatty acid and lipid metabolism. Total RNA sequencing of cells grown under four conditions: one control and three nitrogen starvation conditions; for each condition two biological replicate samples were sequenced, each in four technical replicates (32 samples in total)