|GUO, LI - University Of Massachusetts|
|BREAKSPEAR, ANDREW - University Of Minnesota|
|ZHAO, V - University Of Massachusetts|
|GAO, LIXIN - University Of Massachusetts|
|XU, JIN-RONG - Purdue University|
|MA, LI-JUN - University Of Massachusetts|
Submitted to: PLoS Pathogens
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 6/1/2015
Publication Date: 6/29/2015
Publication URL: http://doi 10.1111/mpp.12272
Citation: Guo, L., Breakspear, A., Zhao, V., Gao, L., Kistler, H.C., Xu, J., Ma, L. 2015. Comparative transcriptomics reveals conservation and divergence of cAMP-PKA pathway in Fusarium graminearum and F. verticillioides. PLoS Pathogens. doi:10.1111/mpp.12272.
Interpretive Summary: Fusarium head blight is one of the most important diseases of wheat and barley world-wide. Effective control measures for the disease are not currently available. We seek to develop new principles and measures for disease management by learning more about the spread and pathogenic adaptation of the fungus causing the disease. Two new genes for a "master switch" controlling pathogenicity in the fungus was discovered by this work. Further knowledge of the genetic basis for pathogenicity may be used to develop alternative approaches to disease management and control. This information will be helpful to plant improvement specialists who are working to develop plants resistant to these pathogens or for developing novel strategies for disease control.
Technical Abstract: The importance of cAMP signaling in fungal development and pathogenesis has been well documented in many fungal species including several phytopathogenic Fusarium spp. Two key components of the cAMP-PKA pathway, adenylate cyclase (AC) and catalytic subunit of PKA (CPKA), have been functionally characterized. However, other genes involved in this signaling pathway and their regulation are not well understood in filamentous fungi. In this study, we performed comparative transcriptomic analysis of AC and CPKA mutants in two closely-related pathogenic ascomycetes F. graminearum (Fg) and F. verticillioides (Fv). Combining the Fg transcriptomics and phenomics data available in the public domain, we reconstructed the Fg cAMP signaling pathway and unveiled subnetworks under its control for regulating key biological processes, such as virulence, sexual reproduction and mycotoxin production. Comparative analysis revealed an overall conservation, at both DNA sequence and gene expression levels, for the 8500 orthologs identified between Fg and Fv genomes. A subset of 482 (6%) orthologous genes exhibited strong expression divergence, which enables the dissection of the conserved and unique portions of the cAMP-PKA pathway in each genome. Whereas the conserved pathways control essential functions such as metabolism, cell cycle, cell transport and protein synthesis in both species, diverged pathways play more species-specific roles such as species specific secondary metabolite biosynthesis pathway and production of macroconidia in Fv. Our results suggest that cAMP signaling pathways are highly conserved; however functional divergence may have occurred through variations in a few key regulators.