Integrated Analysis of Fatty Acid Metabolism and Transcriptome Involved in Olive Fruit Development to Improve Oil Composition

Olea europaea L. is an important oil crop with excellent nutritional properties. In this study, a full-length transcriptome combined with fatty acid composition was used to investigate the molecular mechanism of fatty acid (FA) metabolism of olive fruits at various stages of development (S1-S5). A total of 34 fatty acids (FAs) were measured using gas chromatography-mass spectrometry (GC-MS). All transcripts of FA metabolism during olive fruit development were studied, including glycolysis, fatty acid synthesis, triacylglycerol synthesis, and FA degradation. A total of 100 transcripts of 11 gene families, 68 transcripts of 12 gene families, 55 transcripts of 7 gene families, and 28 transcripts of 7 gene families were identified as encoding for enzymes involved in FA metabolism. Furthermore, one of the critical reactions in TAG metabolism is the activation of fatty acyl chains to fatty acyl CoA, which is catalyzed by long-chain acyl CoA synthetases (LACS). Phylogenetic analysis showed that 13 putative LACS-encoding genes clustered into five groups, of which two putative transcripts encoding LACS6/7 may participate in FA degradation. The aim of this study was to evaluate the fatty acid from synthesis to degradation pathways during olive fruit development to provide a better understanding of the molecular mechanism of FA metabolism during olive fruit maturation and provide information to improve the synthesis of oil components that are beneficial to human health.

Automated summary

By analyzing the fatty acid composition and full-length transcriptome, this study revealed the molecular mechanism of fatty acid metabolism during olive fruit development. Multiple enzymes were found to be involved in fatty acid metabolism, contributing to a better understanding of the process during olive fruit maturation.