RNA-Sequence Analysis Reveals the Cold Adaption Mechanism of Mortierella isabellina M6-22

Mortierella isabellina strain M6-22 was cultured at 15 degrees C (low temperature group) and 30 degrees C (control). RNA sequencing analysis was carried out using total RNA samples isolated from M6-22 in low temperature and control groups. The sequencing datasets were pooled and reads assembly was performed. Unigenes were identified followed by functional annotation and pathway analysis. Prediction of coding sequence was also carried out. Differentially expressed genes (DEGs) were identified by reads per kb per million reads (RPKM) method. Gene ontology (GO) and metabolic pathway enrichment analyses were performed. A total of 2,491 Unigenes were enriched into metabolism-related biological processes such as carbohydrate and lipid transport and metabolism. The types of Unigenes included domain, family and repeat. Overall, 3,847 DEGs including 2,330 up-and 1,517 down-regulated genes were screened out. DEGs were significantly related to the biological functions of lipid transport and metabolism, cellular process, and metabolic pathways. DEGs such as ALAS (5-aminolevulinate synthase), Glycerol 3-phosphate dehydrogenase, tenascin C, glycosyl hydrolase family 43 and DAHPS (3-deoxy-7-phosphoheptulonate synthase) may play key roles in cold-adaption of M6-22 by up-regulating lipid transport and metabolism, cellular process, and biosynthesis of secondary metabolites at low temperature. This work provides basis for exploring the molecular mechanisms underlying cold adaptation of M. isabellina M6-22. (c) 2018 Friends Science Publishers