Browsing by Author "Hristozova, Nevena"

The white rot fungus Heterobasidion annosum s.l. is a basidiomycete which is considered to be the most economical important pathogen of conifer trees (Pinus, Picea and Abies) in the northern hemisphere. Presently, the knowledge on the biology and molecular aspects of the Heterobasidion pathosystem is still poor and this is the major set-back in preventing the spread of the pathogen. A deeper investigation at the molecular level of the pathogenicity factors involved during the infection process is very important to better control the disease. Intra-cellular signal-transduction pathways, and in particular the Mitogen Activated Protein Kinases (MAPKs), have been shown to play key roles in the infection cycle in many fungal pathogens, being pivotal in survival, appressorial formation, sporulation and response to various biotic and abiotic stresses. The aim of this study is to characterize a specific H. annosum MAPK, with high sequence homology to FUS3 gene (involved in mating) in S. cerevisiae and with PMK1 gene (involved in appressoria formation) in Magnaporthe grisea. In order to study the function of this MAPK in H. annosum, we performed a complementation experiment in the S. cerevisiae fus3?? mutant. Expression level profiles, proteomics and immunology studies were used to distinguish between phosphorylated/active and non-phosphorylated/inactive form of the MAPK. Some valuable insights on this kinase cascade in Heterobasidion were discovered, but further studies are required to fully understand its role in the lifecycle of this fungus.