Molecular determinants of host specificity of maize-, rice- and mango-pathogenic species of the genus Fusarium
Final Report Abstract
Our study presents high-quality genome sequences of three additional members of the Asian clade of the FFC, namely F. mangiferae, and two strains of F. proliferatum. We compared the genomes of these strains to those of F. fujikuroi and F. verticillioides, which belong to the Asian and African-clades of the FFC, respectively, and to the closely related but non-FFC species F. oxysporum. We explored the genetic potential of these fusaria to produce SMs, including phytohormones, and tested their ability to produce SMs both in vitro and in planta. Despite the high level of sequence conservation among species, there are several differences in SM gene content and production that have the potential to contribute to host specificity. Transcriptomic analysis of maize tissue individually infected with the five Fusarium isolates revealed SM biosynthetic genes that are upregulated in all the strains and others that were upregulated only in one strain. Among the most remarkable findings are the following: Despite the high level of similarity among the genomes of the sequenced FFC strains, there are SM biosynthetic genes that are unique to each species and may be at least partially responsible for the differences in host specificity or pathogenic versus endophytic life style. Members of the FFC are unique among ascomycetes in their genetic potential to produce three classes of phytohormones: GAs, CKs and auxins. However, the ability to produce these hormones is species- and even strainspecific. In particular, there are fundamental differences between the two F. proliferatum strains in their ability to produce GAs and auxins. These differences in phytohormone biosynthesis may be at least partially responsible for the pathogenic versus endophytic life style. F. mangiferae is able to induce the accumulation of plant CKs and probably to cause mango malformation by this strategy.
Publications
- (2011) Identification and functional characterization of indole-3-acetamide-mediated IAA biosynthesis in plant-associated Fusarium species. Fungal Genet Biol. 49: 48-57
Tsavkelova, E., Oeser, B., Oren-Young, L, Israeli, M., Sasson, Y., Tudzynski, B., Sharon, A.
(See online at https://doi.org/10.1016/j.fgb.2011.10.005) - 2013. Deciphering the Cryptic Genome: Genome-wide Analyses of the Rice Pathogen Fusarium fujikuroi Reveal Complex Regulation of Secondary Metabolism and Novel Metabolites. PLoS Pathog 9(6): e1003475
Wiemann, P., Sieber, CMK., von Bargen, KW., Studt, L., Niehaus, E.M., Espino, JJ, Huß, K., Michielse, CB, Albermann, S., Wagner, D., Bergner, SV, Connolly, LR., Fischer, A., Reuter, G., Kleigrewe, K., Bald, T., Wingfield, BD., Ophir, R., Freeman, S., Hippler, M., Smith, KM., Brown, DW.,Proctor, RH., Münsterkötter, M., Freitag, M., Humpf, H.-U., Güldener, U., and Tudzynski, B.
(See online at https://doi.org/10.1371/journal.ppat.1003475) - (2016) Comparative ‘omics’ of the Fusarium fujikuroi species complex highlights differences in genetic potential and metabolite synthesis. Genome Biology and Evolution 8 (11): 3574-3599
Niehaus EM, Münsterkötter M, Proctor RH, Brown DW, Sharon A, Idan Y, Oren- Young L, Sieber CM, Novák O, Pěnčík A, Tarkowská D, Hromadová K, Freeman S, Maymon M, Elazar M, Youssef SA, El-Shabrawy ESM, Shalaby AA, Houterman P, Brock NL, Burkhardt I, Tsavkelova EM, Dickschat JS, Galuszka P, Güldener U, Tudzynski B
(See online at https://doi.org/10.1093/gbe/evw259)