title: Endocytosis of a maltose permease is induced when amylolytic enzyme production is repressed in Aspergillus oryzae.
abstract: In the filamentous fungus Aspergillus oryzae, amylolytic enzyme production is induced by the presence of maltose. Previously, we identified a putative maltose permease (MalP) gene in the maltose-utilizing cluster of A. oryzae. malP disruption causes a significant decrease in α-amylase activity and maltose consumption, indicating that MalP is a maltose transporter required for amylolytic enzyme production in A. oryzae. Although the expression of amylase genes and malP is repressed by the presence of glucose, the effect of glucose on the abundance of functional MalP is unknown. In this study, we examined the effect of glucose and other carbon sources on the subcellular localization of green fluorescence protein (GFP)-tagged MalP. After glucose addition, GFP-MalP at the plasma membrane was internalized and delivered to the vacuole. This glucose-induced internalization of GFP-MalP was inhibited by treatment with latrunculin B, an inhibitor of actin polymerization. Furthermore, GFP-MalP internalization was inhibited by repressing the HECT ubiquitin ligase HulA (ortholog of yeast Rsp5). These results suggest that MalP is transported to the vacuole by endocytosis in the presence of glucose. Besides glucose, mannose and 2-deoxyglucose also induced the endocytosis of GFP-MalP and amylolytic enzyme production was inhibited by the addition of these sugars. However, neither the subcellular localization of GFP-MalP nor amylolytic enzyme production was influenced by the addition of xylose or 3-O-methylglucose. These results imply that MalP endocytosis is induced when amylolytic enzyme production is repressed.
authors.affiliation: Laboratory of Bioindustrial Genomics, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai 981-8555, Japan.
authors.forename: Tetsuya
authors.initials: T
authors.lastname: Hiramoto
authors.affiliation: Laboratory of Bioindustrial Genomics, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai 981-8555, Japan.
authors.forename: Mizuki
authors.initials: M
authors.lastname: Tanaka
authors.affiliation: Laboratory of Bioindustrial Genomics, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai 981-8555, Japan.
authors.forename: Takanori
authors.initials: T
authors.lastname: Ichikawa
authors.affiliation: Laboratory of Bioindustrial Genomics, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai 981-8555, Japan.
authors.forename: Yuka
authors.initials: Y
authors.lastname: Matsuura
authors.affiliation: Laboratory of Bioindustrial Genomics, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai 981-8555, Japan.
authors.forename: Sachiko
authors.initials: S
authors.lastname: Hasegawa-Shiro
authors.affiliation: Laboratory of Bioindustrial Genomics, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai 981-8555, Japan.
authors.forename: Takahiro
authors.initials: T
authors.lastname: Shintani
authors.affiliation: Laboratory of Bioindustrial Genomics, Department of Bioindustrial Informatics and Genomics, Graduate School of Agricultural Science, Tohoku University, 1-1 Tsutsumidori-Amamiyamachi, Aoba-ku, Sendai 981-8555, Japan. Electronic address: gomi@biochem.tohoku.ac.jp.
authors.forename: Katsuya
authors.initials: K
authors.lastname: Gomi
mesh_terms: D000681:Amylases / Q000378:metabolism*; D001236:Aspergillus oryzae / Q000502:physiology*; D001692:Biological Transport; D004705:Endocytosis; D004789:Enzyme Activation; D015870:Gene Expression; D017930:Genes, Reporter; D005947:Glucose / Q000378:metabolism; D042541:Intracellular Space / Q000378:metabolism; D008320:Maltose / Q000378:metabolism; D009004:Monosaccharide Transport Proteins / Q000378:metabolism*; D011993:Recombinant Fusion Proteins; D044767:Ubiquitin-Protein Ligases / Q000378:metabolism; D000516:alpha-Amylases / Q000378:metabolism
chemical_list: D009004:Monosaccharide Transport Proteins; D011993:Recombinant Fusion Proteins; D008320:Maltose; C021534:maltose permease; D044767:Ubiquitin-Protein Ligases; D000681:Amylases; D000516:alpha-Amylases; D005947:Glucose
keywords: Aspergillus oryzae; Carbon catabolite repression; Endocytosis; Maltose transporter; Ubiquitin ligase; α-Amylase