The effect of multiple copies of the upstream region on expression of the Aspergillus niger glucoamylase-encoding gene.
The regulation of transcription of the glucoamylase-encoding gene (glaA) of Aspergillus niger was studied. To facilitate this study a reporter strain containing a fusion of the glaA promoter (PglaA) of A. niger to the beta-glucuronidase-encoding gene (uidA) of Escherichia coli was constructed. To analyze whether regulatory proteins are involved in the regulation of glaA, multiple copies of PglaA were introduced into this reporter strain. Analysis of the resulting strains revealed that introduction of an increasing number of PglaA copies resulted in lower expression of the uidA reporter gene and the endogenous glaA gene in cultures cultivated on different inducing carbon sources. However, repression by xylose was not influenced by the copy number of PglaA. These results indicate that the expression of genes under control of PglaA are regulated by specific trans-acting regulatory protein(s). Deletion analysis of PglaA indicated that regulatory proteins interact with DNA sequences within 0.5-kb upstream from the ATG, whereas sequences between about 0.8- and 0.5-kb upstream from the ATG are required for high-level expression of glaA.
Verdoes
J C
JC
Department of Molecular Genetics and Gene Technology, TNO Nutrition and Food Research Institute, Rijswijk, The Netherlands.
Punt
P J
PJ
Stouthamer
A H
AH
van den Hondel
C A
CA
D001234:Aspergillus niger / Q000201:enzymology / Q000235:genetics*; D001483:Base Sequence; D050260:Carbohydrate Metabolism; D004252:DNA Mutational Analysis; D004268:DNA-Binding Proteins / Q000378:metabolism; D004790:Enzyme Induction; D004794:Enzyme Repression; D015971:Gene Expression Regulation, Enzymologic; D015966:Gene Expression Regulation, Fungal; D005800:Genes, Fungal / Q000235:genetics*; D017930:Genes, Reporter; D005822:Genetic Vectors; D005087:Glucan 1,4-alpha-Glucosidase / Q000096:biosynthesis / Q000235:genetics*; D008969:Molecular Sequence Data; D005810:Multigene Family / Q000235:genetics; D011401:Promoter Regions, Genetic / Q000235:genetics; D012333:RNA, Messenger / Q000032:analysis; D017384:Sequence Deletion; D012689:Sequence Homology, Nucleic Acid; D014994:Xylose / Q000494:pharmacology
D004268:DNA-Binding Proteins; D012333:RNA, Messenger; D014994:Xylose; D005087:Glucan 1,4-alpha-Glucosidase