[Seminar] The influence of Mitogen activated protein (MAP) kinases on Aspergillus fumigatus virulence and pathogenicity

Seminar

Title: The influence of Mitogen activated protein (MAP) kinases on Aspergillus fumigatus virulence and pathogenicity

Speaker: Gustavo H. Goldman

Affiliation: Faculdade de Ciências Farmacêuticas de Ribeirão Preto, Universidade de São Paulo, Brazil

Host: Cristina Silva Pereira, Applied and Environmental Mycology Lab

Short CV:

Graduate at Biology from Universidade Federal do Rio de Janeiro (1983), master's at Microbiologia from Universidade de São Paulo (1988) and PhD at Molecula Biology from Rijksuniversiteit Gent (1994). He has experience in Genetics, acting on the following subjects: Aspergillus nidulans and Aspergillus fumigatus.

Webpage:

http://buscatextual.cnpq.br/buscatextual/visualizacv.do?id=K4783488J2

Abstract:

Aspergillus fumigatus is a major opportunistic pathogen and allergen of mammals, causing approximately 65% of all invasive fungal infections in humans, while being the mostly encountered species accounting for pulmonary infections. There is a general consensus that aspergillosis is a multifactorial disease with several phenotypes influencing the final outcome of the disease establishment. Factors involved in the establishment of the infection, include hypoxia resistance, iron assimilation, gliotoxin production (depending on the immune status of the host), presence of dihydroxynaphthalene melanin and thermophily. However, it is essential to understand how these traits are coordinated in response to an environmental cue. Hence, a deep understanding of the signalling pathways that regulate these factors involved in virulence is needed. The highly conserved mitogen-activated protein kinase (MAPK) signalling pathways are essential to the adaptation to environmental changes. The MAPK cascades are important for relaying, integrating and amplifying intracellular signals, and are crucial signalling components involved in many cellular processes. In filamentous fungi the conserved MAPK pheromone response, filamentous growth, osmotic stress response and cell wall integrity (CWI) pathways have been shown to influence numerous virulence traits including invasive growth, biofilm formation, mycotoxin production and antifungal tolerance. A. fumigatus has four MAPKs: (i) MpkA, the central regulator of CWI pathway also plays a role in oxidative stress, (ii) MpkB is the putative homologue of filamentous growth/pheromone response pathway, still uncharacterized and (iii) MpkC and SakA, homologues of the Saccharomyces cerevisiae Hog1, constitute the main regulator of the high osmolarity glycerol response (HOG) pathway. SakA and MpkC have also been shown to play a role in caspofungin adaptation and carbon source utilization, respectively. Here, we will provide information regarding the involvement of A. fumigatus MAP kinases in the virulence and drug resistance.