School of Life Sciences, Anhui Agricultural University, Hefei, China.
The National Engineering Laboratory of Crop Stress Resistance Breeding, Anhui Agricultural University, Hefei, China.
Microbiologyopen. 2019 Oct;8(10):e897. doi: 10.1002/mbo3.897. Epub 2019 Jul 22.
Although several regulatory pathways have been reported for Aspergillus flavus, the regulation of aflatoxin production and mycelial growth under different temperatures remains unclear. In this study, A. flavus differentially expressed genes (DEGs) and regulatory pathways were analyzed under three temperatures, by strand-specific RNA-Seq. Results show that a total of 2,428 and 1,474 DEGs were identified in fungal mycelia cultured at 20°C and 37°C, respectively, as compared with the control (28°C). Approximately ~ 79% of DEGs in the 37°C samples were up-regulated genes, while ~ 63% of DEGs in the 20°C samples were down-regulated genes. Most of the DEG pathways enriched by lower temperatures differed from those enriched by higher temperatures, while only a small portion of the pathways were shared by A. flavus grown under different temperatures. Aflatoxin biosynthesis, Butanoate metabolism, oxidation-reduction process, and benzene-containing compound metabolic process were the shared down-regulated pathways, while steroid biosynthesis, oxidoreductase activity, cellular protein modification process, DNA binding, protein complex were the shared up-regulated pathways between lower and higher temperatures. The shared genes and pathways are the key regulatory candidates for aflatoxin biosynthesis with changes of temperature. In addition, the identification of both up-regulated and down-regulated genes provides a useful gene set for further investigation of the aflatoxin biosynthesis among Aspergillus.
虽然已经报道了几种曲霉属黄曲霉的调控途径，但在不同温度下，黄曲霉毒素的产生和菌丝生长的调控仍不清楚。在这项研究中，通过链特异性 RNA-Seq 分析了三种温度下黄曲霉差异表达基因（DEGs）和调控途径。结果表明，与对照（28°C）相比，在 20°C 和 37°C 培养的真菌菌丝中分别鉴定出了 2428 和 1474 个 DEGs。大约79%的 37°C 样本中的 DEGs 是上调基因，而63%的 20°C 样本中的 DEGs 是下调基因。大多数由低温富集的 DEG 途径与由高温富集的途径不同，而只有一小部分途径是黄曲霉在不同温度下生长所共有的。黄曲霉毒素生物合成、丁酸代谢、氧化还原过程和含苯化合物代谢过程是共下调的途径，而甾体生物合成、氧化还原酶活性、细胞蛋白质修饰过程、DNA 结合、蛋白质复合物是低温和高温之间共上调的途径。共享的基因和途径是温度变化时黄曲霉毒素生物合成的关键调控候选基因。此外，上调和下调基因的鉴定为进一步研究曲霉属中黄曲霉毒素的生物合成提供了有用的基因集。
