The Transcriptome and Metabolic Pathways of Persea americana under Drought and Low-temperature Stress

Persea americana Mill. is an important cash crop that contains effective ingredients to reduce cholesterol and protect the cardiovascular system. Presently, the gene regulation mechanism and signal pathway of stress response in P. americana are unclear. To explore the gene expression changes of P. americana under drought and low-temperature stress, the transcripts of P. americana were sequenced under these conditions. The results produced 42,815,960 bp raw reads. Analysis of the related metabolic pathways and differentially expressed genes showed that under drought stress, the gene expression of beta-amylase 3, glyceraldehyde-3phosphate dehydrogenase and hexokinase were upregulated, while the gene expression of UDP-glycosyltransferase superfamily protein isoform, glucose-1-phosphate adenylyltransferase, and glucose-6-phosphate 1epimerase were downregulated. Under low-temperature stress, the expression of beta-amylase and shikimate O-hydroxycinnamoyl transferase genes was downregulated. In addition, WRKY, MYB, bHLH, and NAC transcription factors were expressed under drought and lowtemperature stress. Finally, the RNA-Seq data were validated using realtime fluorescence quantitative analysis to identify the key genes of P. americana regulated at the transcriptional level under drought and lowtemperature stress. This study provides a theoretical basis for the selection of drought-resistant and low-temperature tolerant P. americana varieties.