The conidial tolerance of Metarhizium anisopliae var.anisopliae isolate ARSEF 2575 to UV-B irradiation is greatly influenced by growth-environment alterations.In this review,we report high variability in conidial UV-B...The conidial tolerance of Metarhizium anisopliae var.anisopliae isolate ARSEF 2575 to UV-B irradiation is greatly influenced by growth-environment alterations.In this review,we report high variability in conidial UV-B tolerance in response to altered culture conditions.Conidia produced on insect cadavers[Zophobas morio(Coleoptera)or Galleria mellonella(Lepidoptera)] had low tolerance to UV-B radiation;and conidia produced on potato dextrose agar supplemented with yeast extract(PDAY)had medium UV-B tolerance;whereas conidia produced on a minimal medium without any carbon source(MM),on MM with a non-preferred carbon source such as lactose(=MML),on PDAY plus 1 M NaCl or KCl,or PDBY with high alkalinity had the highest UV-B tolerances.All of the above conditions that induced high UV-B tolerance,however,also greatly reduced conidial production.Comparisons between stress tolerance and conidial production,particularly with conidia produced under osmotic and nutritive stress,point out that the benefits of producing very tolerant conidia have the enormous cost of low conidial production.Growth under visible light also greatly improved conidial UV-B tolerance,but light did not negatively influence conidial production.Therefore,culture on rich media under light is proposed as the most promising approach to producing conidia with improved UV-B tolerance for biological control of pest insects in agriculture.展开更多
The COP9 signalosome(CSN) is a highly conserved multiprotein complex in all eukaryotes and involved in regulation of organism development. In filamentous fungi, several lines of evidence indicate that fungal developme...The COP9 signalosome(CSN) is a highly conserved multiprotein complex in all eukaryotes and involved in regulation of organism development. In filamentous fungi, several lines of evidence indicate that fungal development and secondary metabolism(SM) are mediated by the fifth subunit of CSN, called CsnE. Here we uncover a connection with CsnE and conidial formation as well as SM regulation in the plant endophytic fungus Pestalotiopsis fici. A homology search of the P. fici genome with CsnE, involved in sexual development and SM in Aspergillus nidulans, identified PfCsnE. Deletion of PfcsnE resulted in a mutant that stopped conidial production, but the conidia are recovered in a PfcsnE complemented strain. This indicates that PfCsnE is required for the formation of conidia. Secondary metabolite analysis demonstrated that the ΔPfcsnE strain produced more chloroisosulochrin, less ficiolide A production in comparison to wild type(WT). Transcriptome analysis of WT andΔPfcsnE strains indicated that PfcsnE impacts the expression levels of 8.37% of 14,797 annotated genes. Specifically, nine biosynthetic gene clusters(BGCs) were up-regulated and three BGCs were down-regulated by PfCsnE. Our results suggest that PfCsnE plays major roles in SM regulation and conidial development in P. fici.展开更多
文摘The conidial tolerance of Metarhizium anisopliae var.anisopliae isolate ARSEF 2575 to UV-B irradiation is greatly influenced by growth-environment alterations.In this review,we report high variability in conidial UV-B tolerance in response to altered culture conditions.Conidia produced on insect cadavers[Zophobas morio(Coleoptera)or Galleria mellonella(Lepidoptera)] had low tolerance to UV-B radiation;and conidia produced on potato dextrose agar supplemented with yeast extract(PDAY)had medium UV-B tolerance;whereas conidia produced on a minimal medium without any carbon source(MM),on MM with a non-preferred carbon source such as lactose(=MML),on PDAY plus 1 M NaCl or KCl,or PDBY with high alkalinity had the highest UV-B tolerances.All of the above conditions that induced high UV-B tolerance,however,also greatly reduced conidial production.Comparisons between stress tolerance and conidial production,particularly with conidia produced under osmotic and nutritive stress,point out that the benefits of producing very tolerant conidia have the enormous cost of low conidial production.Growth under visible light also greatly improved conidial UV-B tolerance,but light did not negatively influence conidial production.Therefore,culture on rich media under light is proposed as the most promising approach to producing conidia with improved UV-B tolerance for biological control of pest insects in agriculture.
基金Wenbing Yin is a scholar of "the 100 Talents Project" of Chinese Academy of Sciencessupported by the National Key Research and Development Program (2016YFD0400105)+1 种基金National Natural Science Foundation of China (31670402 and 31400334)Sate Key Laboratory of Mycology Open Project (SKLMKF 2015-1)
文摘The COP9 signalosome(CSN) is a highly conserved multiprotein complex in all eukaryotes and involved in regulation of organism development. In filamentous fungi, several lines of evidence indicate that fungal development and secondary metabolism(SM) are mediated by the fifth subunit of CSN, called CsnE. Here we uncover a connection with CsnE and conidial formation as well as SM regulation in the plant endophytic fungus Pestalotiopsis fici. A homology search of the P. fici genome with CsnE, involved in sexual development and SM in Aspergillus nidulans, identified PfCsnE. Deletion of PfcsnE resulted in a mutant that stopped conidial production, but the conidia are recovered in a PfcsnE complemented strain. This indicates that PfCsnE is required for the formation of conidia. Secondary metabolite analysis demonstrated that the ΔPfcsnE strain produced more chloroisosulochrin, less ficiolide A production in comparison to wild type(WT). Transcriptome analysis of WT andΔPfcsnE strains indicated that PfcsnE impacts the expression levels of 8.37% of 14,797 annotated genes. Specifically, nine biosynthetic gene clusters(BGCs) were up-regulated and three BGCs were down-regulated by PfCsnE. Our results suggest that PfCsnE plays major roles in SM regulation and conidial development in P. fici.
