INVESTIGADORES
AGUILAR Pablo S.
artículos
Título:
FigA, a Putative Homolog of Low-Affinity Calcium System Member Fig1 in Saccharomyces cerevisiae, Is Involved in Growth and Asexual and Sexual Development in Aspergillus nidulans
Autor/es:
ZHANG, S.; ZHENG, H.; LONG, N.; CARBÓ, N.; CHEN, P.; AGUILAR, P.S. AND LUA, L.
Revista:
EUKARYOTIC CELL
Editorial:
AMER SOC MICROBIOLOGY
Referencias:
Lugar: Washington; Año: 2014 vol. 13 p. 295 - 303
ISSN:
1535-9778
Resumen:
Calcium-mediated signaling pathways are widely employed in eukaryotes and are implicated in the regulation of diverse biologi-
cal processes. In Saccharomyces cerevisiae, at least two different calcium uptake systems have been identified: the high-affinity
calcium influx system (HACS) and the low-affinity calcium influx system (LACS). Compared to the HACS, the LACS in fungi is
not well known. In this study, FigA, a homolog of the LACS member Fig1 from S. cerevisiae, was functionally characterized in
the filamentous fungus Aspergillus nidulans. Loss of figA resulted in retardant hyphal growth and a sharp reduction of conidial
production. Most importantly, FigA is essential for the homothallic mating (self-fertilization) process; further, FigA is required
for heterothallic mating (outcrossing) in the absence of HACS midA. Interestingly, in a figA deletion mutant, adding extracellu-
lar Ca2 rescued the hyphal growth defects but could not restore asexual and sexual reproduction. Furthermore, quantitative
PCR results revealed that figA deletion sharply decreased the expression of brlA and nsdD, which are known as key regulators
during asexual and sexual development, respectively. In addition, green fluorescent protein (GFP) tagging at the C terminus of
FigA (FigA::GFP) showed that FigA localized to the center of the septum in mature hyphal cells, to the location between vesicles
and metulae, and between the junctions of metulae and phialides in conidiophores. Thus, our findings suggest that FigA, apart
from being a member of a calcium uptake system in A. nidulans, may play multiple unexplored roles during hyphal growth and
asexual and sexual development.