This is a preprint, a preliminary version of a manuscript that has not completed peer review at a journal. Research Square does not conduct peer review prior to posting preprints. The posting of a preprint on this server should not be interpreted as an endorsement of its validity or suitability for dissemination as established information or for guiding clinical practice.
Research
Weifa Zheng
Jiangsu Normal University
Corresponding Author
License:
This work is licensed under a CC BY 4.0 License. Read Full License
The formation of propagules (conidia and ascospores) is the critical stage for the transmission of the pathogenic fungus Stemphylium eturmiunum. However, how the development of these propagules is regulated remains to be fully understood. Here, we show that nitric oxide (NO) is necessary for the formation of conidia and pseudothecia in S. eturmiunum. Application of NO scavenger carboxy-CPTIO (cPTIO) or soluble guanylate cyclase (sGC) inhibitor NS2028 abolishes the formation of conidia and pseudothecia. In the culture of S. eturmiunum, supplement of NO-releasing compound sodium nitroprusside (SNP) results in an increased formation of conidia at 0.2 mmol/L, and pseudothecia at 2 mmol/L. SNP supplement also triggered increased biosynthesis of melanin, which can be inhibited partially upon the addition of either arbutin or tricyclazole, the specific inhibitors for 3,4-dihydroxyphenylalanine (DOPA) and dihydroxynaphthalene (DHN) synthetic pathway, respectively. Intriguingly, enhanced melanin biosynthesis triggered an increased formation of propagules; while its inhibition impaired their formation. The SNP-induced increment in the formation of propagules can be also compromised upon supplement of cPTIO or NS-2028. RT-PCR analysis showed that SNP at 0.2 mmol/L promoted transcription of the genes encoding the conidiation co-regulators brlA, abA, and wetA, and inhibited at 2 mmol/L. In contrast, application of SNP at 2 mmol/L increased transcription of the genes encoding mat1, and mat2, the genes related to sexual reproduction, and the transcription of two DNH melanin synthetic genes pks1 and pks2, and the key gene tyr for DOPA melanin biosynthesis. However, the increased transcription of these genes is down-regulated or blocked upon supplement of cPTIO or NS-2028. Thus, NO regulates asexual and sexual development, as well as melanin synthesis in S. eturmiunum possibly through NO-sGC-GMP signaling pathway.
Keywords
pseudothecia, conidia, sodium nitroprusside, polyketide synthase, tyrosinase
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
Figure 6
Figure 7
Figure 8
Figure 9
Figure 10
Loading...
Badges
Prescreen
This manuscript passed our Prescreen assessment
Complete author information
Appropriate declaration statements
Potential risks to human health
Prescreen
History
CURRENT STATUS: Posted
Version 1
Posted 09 Sep, 2020
No community comments so far
Metrics
Comments: 0
PDF Downloads: ...
HTML Views: ...
Subject Areas
Infectious Diseases
Learn more about our company.
This is a preprint. It has not completed peer review.
Research
Weifa Zheng
Jiangsu Normal University
Corresponding Author
Badges
Prescreen
This manuscript passed our Prescreen assessment
Complete author information
Appropriate declaration statements
Potential risks to human health
Prescreen
History
CURRENT STATUS: Posted
Version 1
Posted 09 Sep, 2020
No community comments so far
Metrics
Comments: 0
PDF Downloads: ...
HTML Views: ...
Subject Areas
Infectious Diseases
License:
This work is licensed under a CC BY 4.0 License. Read Full License
The formation of propagules (conidia and ascospores) is the critical stage for the transmission of the pathogenic fungus Stemphylium eturmiunum. However, how the development of these propagules is regulated remains to be fully understood. Here, we show that nitric oxide (NO) is necessary for the formation of conidia and pseudothecia in S. eturmiunum. Application of NO scavenger carboxy-CPTIO (cPTIO) or soluble guanylate cyclase (sGC) inhibitor NS2028 abolishes the formation of conidia and pseudothecia. In the culture of S. eturmiunum, supplement of NO-releasing compound sodium nitroprusside (SNP) results in an increased formation of conidia at 0.2 mmol/L, and pseudothecia at 2 mmol/L. SNP supplement also triggered increased biosynthesis of melanin, which can be inhibited partially upon the addition of either arbutin or tricyclazole, the specific inhibitors for 3,4-dihydroxyphenylalanine (DOPA) and dihydroxynaphthalene (DHN) synthetic pathway, respectively. Intriguingly, enhanced melanin biosynthesis triggered an increased formation of propagules; while its inhibition impaired their formation. The SNP-induced increment in the formation of propagules can be also compromised upon supplement of cPTIO or NS-2028. RT-PCR analysis showed that SNP at 0.2 mmol/L promoted transcription of the genes encoding the conidiation co-regulators brlA, abA, and wetA, and inhibited at 2 mmol/L. In contrast, application of SNP at 2 mmol/L increased transcription of the genes encoding mat1, and mat2, the genes related to sexual reproduction, and the transcription of two DNH melanin synthetic genes pks1 and pks2, and the key gene tyr for DOPA melanin biosynthesis. However, the increased transcription of these genes is down-regulated or blocked upon supplement of cPTIO or NS-2028. Thus, NO regulates asexual and sexual development, as well as melanin synthesis in S. eturmiunum possibly through NO-sGC-GMP signaling pathway.
Figure 1
Figure 2
Figure 3
Figure 4
Figure 5
Figure 6
Figure 7
Figure 8
Figure 9
Figure 10
Loading...