Some of our research focuses on the Arbuscular Mycorrhizal Fungi (AMF). These organisms are prominent root symbionts of most land plants, as they improves plant's uptake of nutrients from the soil and boost plant fitness in terrestrial ecosystems and agriculture. For this reason, AMF are commonly used in organic practices - i.e. organic farming, plant nurseries) and phytoremediation programs.
AMF are also harbor unique from cellular traits, including the co-existence of thousands of nuclei within a large cytoplasm - i.e. syncitium - and lack of visible sexual reproduction and the genome organization of this atypical genetic system has been poorly understood. Our lab has recently made breakthroughs in this area of research, by demonstrating that AMF genetics follow mendelian-like genetics, and that genetic variability in this lineage is most likely triggered by conventional mating processes.
Ultimately, these findings will open avenues for the production of AMF strains tailored for optimized plant growth. To reach this goal, our team continues to identify the molecular and genetic mechanism involved in partner recognition in this fungal group.
Research Highlights:
- Discovery of extensive genome and epigenetic diversity in a model AMF: Chen et al. 2018, New Phytologist; Yildirir 2022, New Phytologist
- First evidence of a homo-heterokaryotic organization in AMF: Ropars et al 2016, Nature Microbiology; Corradi and Brachmann, Trends in Plant Science
- ^Host and strain induced nuclear dynamics in AMF: Kokkoris et al. 2021, Current Biology; Cornell et al. 2022, Fungal Genetics and Biology
- Comparative genomics and phylogenomics of early branching AMF lineages: Malar et al. 2021, Current Biology; Malar et al. 2022, Microbial Genomics
Microsporidian Parasites and Allies
Our lab also specializes in the analysis of a ubiquitous group of obligate intracellular parasites, called Microsporidia. These organisms infect virtually all animals, including humans,and many species of economic importance, such as salmon, honeybees or the silkworm. In humans, microsporidiosis -i.e. the disease associated with microsporidia infections - is usually benign, but it can lead to severe symptoms such as chronic diarrhoea and encephalitis; in immuno-compromised patients.
The are obligate intracellular parasites, and this is reflected in the size and content of their genomes. Specifically, these are almost always gene poor and, in some cases, extremely small and compact - i.e. the smallest known is only 2.3Mb! Our lab has been involved in genome sequencing projects of many species in this group, as a mean to better understand their biology. Our research resulted in the first population genomic analysis of microsporidians, and are now developing experimental population analyses of these parasites. In this area, our research focuses mainly on species of veterinary (Encephalitozoon sp., a common vertebrate pathogen), scientific (Pseudoloma neurophila; a pathogen of the model Zebrafish) and economic importance (Nosema ceranae, a relevant honeybee parasite).
More recently, the microsporidian Nosema ceranae has hit the spotlight for being associated with global declines in honeybee populations. Our lab has revealed that this parasite has spread globally through human intervention, most likely via international commerce of beehives. We also showed that the N. ceranae genome is polyploidy, an atypical genome organization that increases genetic diversity in global populations of this parasite.
Research Highlights:
- For a review on microsporidian genomics and evolution: Corradi N. 2015. Annual Review of Microbiology
- Detection of atypical nuclear complexity and human driven dispersion in honeybee pathogens: Pelin A. et. al. 2015. Environmental Microbiology.
- Discovery of unusual gene-acquisitions in vertebrate parasites: Selman M. et al. 2011. Current Biology.
