Daniele Armaleo, Associate Professor Of The Practice
PhD, Duke University, 1984
Office Location: BioSci: 0052
Office Phone: (919) 660-7326
Email Address: email@example.com
Cell and Molecular Biology
Research Categories: Developmental and molecular biology of symbiosis in lichens
Research Description: My current research centers on the developmental and molecular biology of lichens, well differentiated symbioses between two or three unrelated organisms: specialized fungi on the one hand and algae or cyanobacteria on the other. The 13,500 known lichen species represent 50% of all known ascomycete fungi, are widespread throughout most terrestrial ecosystems, and often tolerate extreme temperatures and dryness. The photosynthetic partner is known to fix the carbon (and the nitrogen when cyanobacteria are involved) necessary for the survival of both symbionts. Lichen fungi and algae can be cultured separately, in an undifferentiated state. However, the in vitro reconstitution of a differentiated lichen from the isolated symbionts is still more of an art than a science. We use as model system the lichen Cladonia grayi and its isolated symbionts. One track involves the study of the biology of depsides, depsidones and dibenzofurans, a unique polyketide class of secondary metabolites produced by lichen fungi. Are these compounds central to the symbiotic interactions between lichen algae and fungi? How are they synthesized and delivered to the external surfaces of the hyphae in specific areas of the lichen thallus? Another track seeks to address broader aspects of the lichen symbiosis (1) by assessing the involvement in it of genomic DNA methylation and (2) by developing an in vitro model for the lichenization process, using axenically cultured symbiotic partners. A third track, recently started in collaboration with Francois Lutzoni (Biology) and Fred Dietrich (Molecular Genetics and Microbiology), involves 454 sequencing of the genomes of the C. grayi symbionts.
- D. Armaleo, X. Sun, C. Culbeson, Insights from the First Biosynthetic Gene Cluster for a Lichen Depside and Depsidone, Mycologia, vol. 103 no. 4 (July, 2011), pp. 741-754 [pdf] [abs].
- S. Joneson, D. Armaleo, F. Lutzoni, Fungal and algal gene expression in early developmental stages of lichen-symbiosis, Mycologia (September 19, 2010) [pdf], [doi] [abs].
- D. Armaleo, S. May, Sizing the fungal and algal genomes of the lichen Cladonia grayi through quantitative PCR, Symbiosis, vol. 49 (2009), pp. 43-51 [pdf] [abs].
- D. Armaleo, Yi Zhang, Sonia Cheung, Light might regulate divergently depside and depsidone accumulation in the lichen Parmotrema hypotropum by affecting thallus temperature and water potential, Mycologia, vol. 100 no. 4 (2008), pp. 565-576 [pdf] [abs] [author's comments].
- D. Armaleo and V. Miao, Symbiosis and DNA methylation in the Cladonia lichen fungus, vol. 26 (1999), pp. 143-163 [pdf] [abs].
Duke Biology Box 90338 Durham, NC 27708 Phone: 919-660-7372 Fax: 919-660-7293