(Universidad Pública de Navarra / Nafarroako Unibertsitate Publikoa, 2006) Peñas Parrila, María Manuela; Azparren Larraya, María Goretti; Domínguez, A.; Sommer, H.; Ramírez Nasto, Lucía; Pisabarro de Lucas, Gerardo; Producción Agraria; Nekazaritza Ekoizpena
Copper homeostasis is primordial for life maintenance and especially relevant
for ligning-degrading fungi whose phenol-oxidase enzymes depend on
this micronutrient for their activity. In this paper we report the identification
of a gene (ctr1), coding for a copper transporter in the white rot fungus Pleurotus
ostreatus, in a cDNA library constructed from four-days old vegetative
mycelium growing in submerged culture. The results presented here indicate
that: (1) ctr1 functionally complements the respiratory deficiency of a yeast
mutant defective in copper transport supporting the transport activity of the
Ctr1 protein; (2) ctr1 transcription is detected in all P. ostreatus developmental
stages (with exception of lamellae) and is negatively regulated by the presence
of copper in the culture media; (3) ctr1 is a single copy gene that maps
to P. ostreatus linkage group III; and (4) the regulatory sequence elements
found in the promoter of ctr1 agree with those found in other copper related
genes described in other systems. These results provide the first description
of a copper transporter in this white rot fungus and open the possibility of
further studies on copper metabolism in higher basidiomyetes.
