Livro das Actas - advid

species worldwide. The wide variety of observed symptoms in different plant and tissues,
and the high variability observed in molecular approaches to B. cinerea have proved
that the fungus can develop multiple different strategies to complete the infection cycle.
The mechanism developed by the phytopathogenic fungi B.cinerea to infect different
plant tissues is a very complex process. The pathogen must choose the right initial time
point to start, or not, every stage of its infective cycle. In addition each of these stages
is accompanied by the development and synthesis of infective structures (germ tube, appressorium,
etc.) and enzymes and toxins, which are necessary for a normal development
of the infective cycle too (Van Kan et al, 2006). In this process the surronding environment
is crucial for fungal development. In this sense the cellular signaling cascades constitutes
the communication bridge between environmental conditions and the cellular
machinery of the organism, and therefore they are responsible for regulating the development
of the fungus, as well as its infective stages All this process is based in transport
and signal transduction from the outside to the cytosol and the nucleus, being involved
in this event an increasing number of proteins from the beginning of the stimulus through
the adhesion of one or more ligands to membrane receptors, until activation of a effectors
set that will convert that stimulus in a particular physiological response.
Membrane proteins play a key role throughout this process as a primary triggers in signaling
cascades, since from these receptors the stimulus is transmitted into the cell
through various posttranslational modifications of proteins involved in the signaling cascade.
Between these modifications, protein phosphorilation/dephosphorilation is one of
the most relevant and widely studied. To date, there is not a description of these proteins
function in the pathogenic fungi infection cycle, only partial functions are known by
gene to gene aproaches. However, in B. cinerea BMP1 gene which coding for a MAP
kinase has emerged as one of three pathogenicity factors known to date in this pathogen
(Zheng et al., 2000). Besides this, it has been shown the role of this signaling pathway
regulated by MAP kinases in the regulation of the growth, differentiation, survival, and
pathogenesis in different fungal pathogens (Xu, 2000). As a result of the great relevance
of these signaling cascades in the infective cycle of fungal pathogens is critical to decipher
the set of proteins involved in these networks. These studies have traditionally been
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