Next Article in Journal
Next Article in Special Issue
Previous Article in Journal
Previous Article in Special Issue
Int. J. Mol. Sci. 2008, 9(10), 2027-2043; doi:10.3390/ijms9102027
Article

Aspergillus parasiticus crzA, Which Encodes Calcineurin Response Zinc-Finger Protein, Is Required for Aflatoxin Production under Calcium Stress

Received: 16 September 2008; in revised form: 27 October 2008 / Accepted: 28 October 2008 / Published: 29 October 2008
Download PDF [737 KB, uploaded 19 June 2014]
Abstract: Two morphologically different Aspergillus parasiticus strains, one producing aflatoxins, abundant conidia but few sclerotia (BN9) and the other producing O-methylsterimatocystin (OMST), copious sclerotia but a low number of conidia (RH), were used to assess the role of crzA which encodes a putative calcium-signaling pathway regulatory protein. Under standard culture conditions, BN9ΔcrzA mutants conidiated normally but decreased slightly in radial growth, regardless of illumination conditions. RHΔcrzA mutants produced only conidia under light and showed decreased conidiation and delayed sclerotial formation in the dark. Regulation of conidiation of both A. parasiticus strains by light was independent of crzA. Increased concentrations of lithium, sodium, and potassium impaired conidiation and sclerotial formation of the RHΔcrzA mutants but they did not affect conidiation of the BN9ΔcrzA mutants. Vegetative growth and asexual development of both ΔcrzA mutants were hypersensitive to increased calcium concentrations. Calcium supplementation (10 mM) resulted in 3-fold and 2-fold decreases in the relative expression of the endoplasmic reticulum calcium ATPase 2 gene in the BN9 and RH parental strains, respectively, but changes in both ΔcrzA mutants were less significant. Compared to the parental strains, the ΔcrzA mutants barely produced aflatoxins or OMST after the calcium supplementation. The relative expression levels of aflatoxin biosynthesis genes, nor1, ver1, and omtA, in both ΔcrzA mutants were decreased significantly, but the decreases in the parental strains were at much lower extents. CrzA is required for growth and development and for aflatoxin biosynthesis under calcium stress conditions.
Keywords: Aspergillus parasiticus; aflatoxin biosynthesis; endoplasmic reticulum calcium ATPase; crzA; calcium homeostasis Aspergillus parasiticus; aflatoxin biosynthesis; endoplasmic reticulum calcium ATPase; crzA; calcium homeostasis
This is an open access article distributed under the Creative Commons Attribution License which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Export to BibTeX |
EndNote


MDPI and ACS Style

Chang, P.-K. Aspergillus parasiticus crzA, Which Encodes Calcineurin Response Zinc-Finger Protein, Is Required for Aflatoxin Production under Calcium Stress. Int. J. Mol. Sci. 2008, 9, 2027-2043.

AMA Style

Chang P-K. Aspergillus parasiticus crzA, Which Encodes Calcineurin Response Zinc-Finger Protein, Is Required for Aflatoxin Production under Calcium Stress. International Journal of Molecular Sciences. 2008; 9(10):2027-2043.

Chicago/Turabian Style

Chang, Perng-Kuang. 2008. "Aspergillus parasiticus crzA, Which Encodes Calcineurin Response Zinc-Finger Protein, Is Required for Aflatoxin Production under Calcium Stress." Int. J. Mol. Sci. 9, no. 10: 2027-2043.


Int. J. Mol. Sci. EISSN 1422-0067 Published by MDPI AG, Basel, Switzerland RSS E-Mail Table of Contents Alert