Evidence of a Ca2+- NO-cGMP signaling pathway controlling zoospore biogenesis in the aquatic fungus Blastocladiella emersonii

Vieira, André Luiz Gomes; Linares, Edlaine; Augusto, Ohára; Gomes, Suely L.

doi:10.1016/j.fgb.2009.04.002

Cited by 40 publications

(51 citation statements)

References 52 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In animals the biosynthesis of NO is primarily catalyzed by the enzyme nitric oxide synthase (18), and in plants the production of NO is catalyzed by nitrate reductase, xanthine oxidoreductase, certain plasma membrane-bound enzymes, and NOS-like enzymes (5). NOS activities have been found in several other fungi (19,26,29,35). Our results confirmed NOS activity in C. minitans as evidenced by the conversion of L-[…”

Section: Discussionsupporting

confidence: 81%

“…Nitric oxide has been detected in many fungi, including C. minitans (15,19,20,29,30), but its origin in fungi is still unknown. In animals the biosynthesis of NO is primarily catalyzed by the enzyme nitric oxide synthase (18), and in plants the production of NO is catalyzed by nitrate reductase, xanthine oxidoreductase, certain plasma membrane-bound enzymes, and NOS-like enzymes (5).…”

Section: Discussionmentioning

confidence: 99%

“…NOS genes have been identified and cloned from animals but not from plants nor fungi. Recently, DNA sequences coding for hypothetical NOS-like proteins have been annotated in some fungal genomes, such as P. blakesleeanus and Magnaporthe grisea (29); however, the putative NOS-like gene remains to be identified.…”

Section: Discussionmentioning

confidence: 99%

“…Both NO function and nitric oxide synthase (NOS) activity have been identified in fungi. NO plays roles in asexual spore development in the ascomycete Neurospora crassa (19), the zygomycete Phycomyces blakesleeanus (15), and the blastocladiomycete Blastocladiella emersonii (29), as well as C. minitans (11). NO stimulates the formation of sexual fruiting bodies in the basidiomycete Flammulina velutipes (26).…”

mentioning

confidence: 99%

See 3 more Smart Citations

Cyclic GMP as a Second Messenger in the Nitric Oxide-Mediated Conidiation of the Mycoparasite Coniothyrium minitans

Fù

Xiè

et al. 2010

Appl Environ Microbiol

View full text Add to dashboard Cite

Understanding signaling pathways that modulate conidiation of mitosporic fungi is of both practical and theoretical importance. The enzymatic origin of nitric oxide (NO) and its roles in conidiation by the sclerotial parasite Coniothyrium minitans were investigated. The activity of a nitric oxide synthase-like (NOS-like) enzyme was detected in C. minitans as evidenced by the conversion of L-arginine to L-citrulline. Guanylate cyclase (GC) activity was also detected indirectly in C. minitans with the GC-specific inhibitor 1H-[1,2,4]oxadiazolo[4,3-a]quinoxalin-1-one (ODQ), which significantly reduced production of cyclic GMP (cGMP). The dynamics of NOS activity were closely mirrored by the cGMP levels during pycnidial development, with the highest levels of both occurring at the pycnidial initiation stage of C. minitans. Furthermore, the NO donor, sodium nitroprusside (SNP), stimulated the accumulation of cGMP almost instantly in mycelium during the hyphal growth stage. When the activity of NOS or GC was inhibited with N-nitro-L-arginine or ODQ, conidial production of C. minitans was suppressed or completely eliminated; however, the suppression of conidiation by ODQ could be reversed by exogenous cGMP. The results also showed that conidiation of an L-arginine auxotroph could be restored by the NO donor SNP, but not by cGMP. Thus, NO-mediated conidiation has more than one signal pathway, including the cGMP signal pathway and another yet-unknown pathway, and both are essential for conidiation in C. minitans.Coniothyrium minitans is a sclerotial parasite of the notorious plant pathogen Sclerotinia sclerotiorum, and its potential for biological control of Sclerotinia diseases has been well demonstrated in several countries (13,17,21,28,33,34,36,37). Efficient production of conidia will further enhance the potential of C. minitans as a biological control agent. Understanding signaling pathways that modulate conidiation of C. minitans will not only facilitate manipulation of the biocontrol agent for commercial use but also advance our understanding of fungal biology.Nitric oxide (NO) is a widespread signaling molecule involved in regulation of a wide range of cellular functions in animals and plants (7). NO synthesis and signaling have been well studied in animals and plants. In mammals, NO plays roles in relaxation of smooth muscle, inhibition of platelet aggregation, neural communication and immune regulation, while in plants NO is involved in disease resistance, abiotic stress, cell death, respiration, senescence, root development, seed germination, and other functions (reviewed in references 6 and 32). NO is also involved in the development of several members of the mycetozoa, such as, Dictyostelium discoideum (10) and Physarum polycephalum (27). The wide variety of effects reflects the basic signaling mechanism that is used by mammals, plants, and virtually all organisms (2). Despite of the extensive research on NO synthesis and signaling processes in animals and plants, our knowledge about NO in fungi is very limi...

show abstract

Section: Discussionsupporting

confidence: 81%

Section: Discussionmentioning

confidence: 99%

Section: Discussionmentioning

confidence: 99%

mentioning

confidence: 99%

See 2 more Smart Citations

Cyclic GMP as a Second Messenger in the Nitric Oxide-Mediated Conidiation of the Mycoparasite Coniothyrium minitans

Fù

Xiè

et al. 2010

Appl Environ Microbiol

View full text Add to dashboard Cite

show abstract

“…In the present work, large-scale gene expression analyses were carried out during the sporulation phase in order to determine the changes in gene expression pattern during zoospore biogenesis. Data presented show that the complexity of the B. emersonii sporulation process is associated with the induction of several genes involved in distinct signaling pathways, including those involving in cyclic GMP (cGMP) synthesis and degradation, which do not seem to be commonly found in fungi (41). Intense cytoskeleton activity is also required, particularly during late sporulation events, as suggested by the upregulation of genes related to this functional category.…”

Section: Resultsmentioning

confidence: 95%

Global Gene Expression Analysis during Sporulation of the Aquatic Fungus Blastocladiella emersonii

Vieira

Gomes

2010

Eukaryot Cell

Self Cite

View full text Add to dashboard Cite

The Blastocladiella emersonii life cycle presents a number of drastic biochemical and morphological changes, mainly during two cell differentiation stages: germination and sporulation. To investigate the transcriptional changes taking place during the sporulation phase, which culminates with the production of the zoospores, motile cells responsible for the dispersal of the fungus, microarray experiments were performed. Among the 3,773 distinct genes investigated, a total of 1,207 were classified as differentially expressed, relative to time zero of sporulation, at at least one of the time points analyzed. These results indicate that accurate transcriptional control takes place during sporulation, as well as indicating the necessity for distinct molecular functions throughout this differentiation process. The main functional categories overrepresented among upregulated genes were those involving the microtubule, the cytoskeleton, signal transduction involving Ca 2؉ , and chromosome organization. On the other hand, protein biosynthesis, central carbon metabolism, and protein degradation were the most represented functional categories among downregulated genes. Gene expression changes were also analyzed in cells sporulating in the presence of subinhibitory concentrations of glucose or tryptophan. Data obtained revealed overexpression of microtubule and cytoskeleton transcripts in the presence of glucose, probably causing the shape and motility problems observed in the zoospores produced under this condition. In contrast, the presence of tryptophan during sporulation led to upregulation of genes involved in oxidative stress, proteolysis, and protein folding. These results indicate that distinct physiological pathways are involved in the inhibition of sporulation due to these two classes of nutrient sources.The life cycle of Blastocladiella emersonii, an aquatic fungus of the class Blastocladiomycetes, involves a series of complex morphological and biochemical events, which involve transcriptional, posttranscriptional, and posttranslational mechanisms of control, especially during two stages of cell differentiation, the germination and the sporulation of the fungus (21). Germination starts with the zoospore, a motile uninucleated wall-less nongrowing cell, which is responsible for the dispersal of the fungus. In the presence of appropriate stimuli, the zoospore germinates, undergoing a number of biochemical and morphological changes. The early events of germination, which include retraction of the single polar flagellum, construction of a cell wall rich in chitin, and cleavage of a giant mitochondrion into normal-size ones, do not require concomitant RNA and protein synthesis and involve posttranslational regulatory events (17,20,30,31,35,36). Major changes in the pattern of RNA and protein synthesis are observed only at the late events of this stage, when the germ tube begins to branch, giving rise to a rhizoidal system through which nutrients are absorbed, and when the cells enter the vegetative growth phase (17,20...

show abstract

NO Synthesis in Subcellular Compartments of Fungi

Röszer

2012

The Biology of Subcellular Nitric Oxide

View full text Add to dashboard Cite

Evidence of a Ca2+- NO-cGMP signaling pathway controlling zoospore biogenesis in the aquatic fungus Blastocladiella emersonii

Cited by 40 publications

References 52 publications

Cyclic GMP as a Second Messenger in the Nitric Oxide-Mediated Conidiation of the Mycoparasite Coniothyrium minitans

Cyclic GMP as a Second Messenger in the Nitric Oxide-Mediated Conidiation of the Mycoparasite Coniothyrium minitans

Global Gene Expression Analysis during Sporulation of the Aquatic Fungus Blastocladiella emersonii

NO Synthesis in Subcellular Compartments of Fungi

Contact Info

Product

Resources

About