title: The high-affinity phosphodiesterase PdeH regulates development and aflatoxin biosynthesis in Aspergillus flavus.
abstract: Cyclic AMP signaling controls a range of physiological processes in response to extracellular stimuli in organisms. Among the signaling cascades, cAMP, as a second messenger, is orchestrated by adenylate cyclase (biosynthesis) and cAMP phosphodiesterases (PDEs) (hydrolysis). In this study, we investigated the function of the high-affinity (PdeH) and low-affinity (PdeL) cAMP phosphodiesterase from the carcinogenic aflatoxin producing fungus Aspergillus flavus, and found that instead of PdeL, inactivation of PdeH exhibited a reduction in conidiation and sclerotia formation. However, the ΔpdeL/ΔpdeH mutant exhibited an enhanced phenotype defects, a similar phenotype defects to wild-type strain treated with exogenous cAMP. The activation of PKA activity was inhibited in the ΔpdeH or ΔpdeL/ΔpdeH mutant, both of whom exhibited increasing AF production. Further analysis by qRT-PCR revealed that pdeH had a high transcriptional level compared to pdeL in wild-type strain, and affected pdeL transcription. Green fluorescent protein tagging at the C-terminus of PDEs showed that PdeH-GFP is broadly compartmentalized in the cytosol, while PdeL-GFP localized mainly to the nucleus. Overall, our results indicated that PdeH plays a major role, but has overlapping function with PdeL, in vegetative growth, development and AF biosynthesis in A. flavus.
authors.affiliation: Fujian Key Laboratory of Pathogenic Fungi and Mycotoxins, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, and School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
authors.forename: Kunlong
authors.initials: K
authors.lastname: Yang
authors.affiliation: Fujian Key Laboratory of Pathogenic Fungi and Mycotoxins, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, and School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
authors.forename: Yinghang
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Fujian Key Laboratory of Pathogenic Fungi and Mycotoxins, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, and School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
authors.forename: Linlin
authors.initials: L
authors.lastname: Liang
authors.affiliation: Fujian Key Laboratory of Pathogenic Fungi and Mycotoxins, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, and School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
authors.forename: Zhenguo
authors.initials: Z
authors.lastname: Li
authors.affiliation: Fujian Key Laboratory of Pathogenic Fungi and Mycotoxins, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, and School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
authors.forename: Qiuping
authors.initials: Q
authors.lastname: Qin
authors.affiliation: Fujian Key Laboratory of Pathogenic Fungi and Mycotoxins, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, and School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China.
authors.forename: Xinyi
authors.initials: X
authors.lastname: Nie
authors.affiliation: Fujian Key Laboratory of Pathogenic Fungi and Mycotoxins, Key Laboratory of Biopesticide and Chemical Biology of Education Ministry, and School of Life Sciences, Fujian Agriculture and Forestry University, Fuzhou 350002, China. Electronic address: wshyyl@sina.com.
authors.forename: Shihua
authors.initials: S
authors.lastname: Wang
mesh_terms: D000348:Aflatoxins / Q000096:biosynthesis* / Q000235:genetics; D001231:Aspergillus flavus / Q000235:genetics*; D002467:Cell Nucleus / Q000235:genetics; D000242:Cyclic AMP; D015966:Gene Expression Regulation, Fungal; D010727:Phosphoric Diester Hydrolases / Q000235:genetics*; D015398:Signal Transduction; D013172:Spores, Fungal / Q000235:genetics* / Q000254:growth & development
chemical_list: D000348:Aflatoxins; D000242:Cyclic AMP; D010727:Phosphoric Diester Hydrolases
keywords: PKA; Phosphodiesterase; Sclerotia; cAMP