#FEMSmicroBlog: Unlocking the secrets of fungal extracellular vesicles

11-07-2021

In all domains of life, cells release nano-sized lipid vesicles to their outer space, so-called extracellular vesicles. In fungi, these particles have been described in both pathogenic and non-pathogenic species. However, many mysteries remain in fungal extracellular vesicle research, especially about the hidden functions that these vesicles might play during pathogenic or mutualistic interactions. As recently outlined in the short review “Structure, composition and biological properties of fungal extracellular vesicles” in microLife, Juliana Rizzo highlights for the #FEMSmicroBlog the main advances on fungal extracellular vesicles, particularly focusing on fungal species with medical relevance. #FascinatingMicrobes

 

Extracellular vesicles in fungal infections

Extracellular vesicles are tiny particles of complex molecular composition. These versatile vehicles play important roles in human pathologies such as cancer, neurodegenerative and cardiovascular diseases.

Their roles in infectious diseases are gaining substantial attention since extracellular vesicles are considered as universal communication mediators in the microbial world. Still, their importance in neglected diseases, such as systemic mycoses, is underexplored.

Many fungal diseases are associated with high mortality with new pathogenic species and multidrug-resistant strains emerging constantly. Hence, we need to urgently understand fungal biology better to find new strategies to fight fungal infections.

The short review “Structure, composition and biological properties of fungal extracellular vesicles” published in microLife explores what is currently known about extracellular vesicles produced by human fungal pathogens. In fungi, extracellular vesicles act in numerous contexts, such as intercellular and interkingdom communication, mechanisms of drug resistance and regulation of morphogenesis and virulence.

Schematic of fungal extracellular vesicles
Functions of fungal extracellular vesicles. From Rizzo et al. (2021).

It has been shown that fungal extracellular vesicles biogenesis and cargo sorting might be regulated by diverse pathways involving different cellular sites. According to recent studies, these might include direct shedding from the plasma membrane, but also through intracellular membrane trafficking processes.

Further, the review outlines the biological functions of fungal extracellular vesicles and their highly diverse cargo. So far, mainly proteins linked to cell wall biogenesis, stress responses, pathogenesis and transport were identified in extracellular vesicles produced by fungi. Furthermore, different lipid classes, small molecules, RNA and polysaccharides are present in these vesicles, while not all their functions are well understood yet.

 

Open questions about fungal extracellular vesicles

The review further explores how fungal extracellular vesicles are involved in communication between producing species but also with their host. However, fungi seem to regulate the structural organization and composition based on genetic and environmental signals. This results in a more complex picture than previously thought and thus poses many challenges in unravelling the mechanisms underlying extracellular vesicle-mediated transfer of information.

Fungal extracellular vesicle properties are regulated genetically and environmentally, which is a more complex picture than previously thought.

Several questions will drive the future of this research field: 1) What are the cellular origins of extracellular vesicles, and how do fungi regulate their biogenesis genetically?; 2) What are extracellular vesicle-associated biomarkers?; 3) How diverse are their structures across different fungal species?; 4) Do fungal pathogens produce extracellular vesicles during infection, and if so, do pathogen and host cell communicate through extracellular vesicles?

Answering these questions will help us unravel the secrets of fungal extracellular vesicles. This will further broaden our understanding of how fungal pathogens interact with their hosts and how infectious disease progresses.

It might also contribute to the development of new approaches for drug delivery and vaccine platforms in the future. The latter is especially relevant since currently there is no vaccine available for fungal infections.

 

 

About the author of this blog

Dr Juliana RizzoDr. Juliana Rizzo holds a Bachelor in Biological Sciences from Universidade Estadual Paulista (Brazil); Msc. in Microbiology and Ph.D in Biochemistry from Universidade Federal do Rio de Janeiro (Brazil). During her Ph.D, Dr. Rizzo moved to the Albert Einstein College of Medicine (USA) and Institut Pasteur (France) to broaden her scientific perspectives and research collaborations. Currently, Dr. Rizzo is a postdoctoral research fellow in the Department of Mycology at the Institut Pasteur where her research entails understanding the biology of fungal extracellular vesicles, focusing on their genetic regulation and roles in pathogenesis and drug resistance, with the potential to use fungal EVs as promising vaccine platforms for fungal infections. Apart from studying fungal EVs, she is passionate about topics related to microbiology and enjoys applying watercolour paintings and innovative sourdough bread recipes to illustrate and explore the micro-world around her.

About this blog section

The section #FascinatingMicrobes for the #FEMSmicroBlog explains the science behind a paper and highlights the significance and broader context of a recent finding. One of the main goals is to share the fascinating spectrum of microbes across all fields of microbiology.

Do you want to be a guest contributor?
The #FEMSmicroBlog welcomes external bloggers, writers and SciComm enthusiasts. Get in touch if you want to share your idea for a blog entry with us!

Back to top

Leave a Reply

Your email address will not be published. Required fields are marked *

Share this news