FluG affects secretion in colonies of Aspergillus niger.
Antonie Van Leeuwenhoek
; 107(1): 225-40, 2015 Jan.
Article
en En
| MEDLINE
| ID: mdl-25370014
ABSTRACT
Colonies of Aspergillus niger are characterized by zonal heterogeneity in growth, sporulation, gene expression and secretion. For instance, the glucoamylase gene glaA is more highly expressed at the periphery of colonies when compared to the center. As a consequence, its encoded protein GlaA is mainly secreted at the outer part of the colony. Here, multiple copies of amyR were introduced in A. niger. Most transformants over-expressing this regulatory gene of amylolytic genes still displayed heterogeneous glaA expression and GlaA secretion. However, heterogeneity was abolished in transformant UU-A001.13 by expressing glaA and secreting GlaA throughout the mycelium. Sequencing the genome of UU-A001.13 revealed that transformation had been accompanied by deletion of part of the fluG gene and disrupting its 3' end by integration of a transformation vector. Inactivation of fluG in the wild-type background of A. niger also resulted in breakdown of starch under the whole colony. Asexual development of the ∆fluG strain was not affected, unlike what was previously shown in Aspergillus nidulans. Genes encoding proteins with a signal sequence for secretion, including part of the amylolytic genes, were more often downregulated in the central zone of maltose-grown ∆fluG colonies and upregulated in the intermediate part and periphery when compared to the wild-type. Together, these data indicate that FluG of A. niger is a repressor of secretion.
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Bases de datos:
MEDLINE
Asunto principal:
Aspergillus niger
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Proteínas Represoras
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Proteínas Fúngicas
Idioma:
En
Revista:
Antonie Van Leeuwenhoek
Año:
2015
Tipo del documento:
Article
País de afiliación:
Países Bajos