title: Selective transport between heterogeneous hyphal compartments via the plasma membrane lining septal walls of Aspergillus niger.
abstract: Hyphae of ascomycetes are compartmentalized by septa. The central pore in these septa allows for cytoplasmic streaming. However, many of these pores are closed by Woronin bodies in Aspergillus, which prevents cytoplasmic mixing and thus maintains hyphal heterogeneity. Here, glucose uptake and transport was studied in Aspergillus niger. Glucose uptake was higher in the hyphal population with high transcriptional activity when compared to the population with low transcriptional activity. Glucose was transported from the colony center to the periphery, but not vice versa. This unidirectional flow was similar in the wild-type and the ΔhexA strain that does not form Woronin bodies. This indicated that septal plugging by Woronin bodies does not impact long distance glucose transport. Indeed, the glucose analogue 2-NBDG (2-(N-[7-nitrobenz-2-oxa-1,3-diazol-4-yl]amino)-2-deoxyglucose) translocated to neighboring hyphal compartments despite Woronin body mediated plugging of the septum that separated these compartments. Notably, 2-NBDG accumulated in septal cross walls, indicating that intercompartmental glucose transport is mediated by transporters that reside in the plasma membrane lining the septal cross-wall. The presence of such transporters would thus enable selective transport between heterogeneous compartments.
authors.affiliation: Microbiology and Kluyver Center for Genomics of Industrial Fermentation, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands; Manchester Fungal Infection Group, Institute of Inflammation and Repair, University of Manchester, CTF Building, 46 Grafton Street, Manchester M13 9NT, United Kingdom. Electronic address: robert-jan.bleichrodt@manchester.ac.uk.
authors.forename: Robert-Jan
authors.initials: RJ
authors.lastname: Bleichrodt
authors.affiliation: Microbiology and Kluyver Center for Genomics of Industrial Fermentation, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands. Electronic address: armanvinck@gmail.com.
authors.forename: Arman
authors.initials: A
authors.lastname: Vinck
authors.affiliation: Manchester Fungal Infection Group, Institute of Inflammation and Repair, University of Manchester, CTF Building, 46 Grafton Street, Manchester M13 9NT, United Kingdom. Electronic address: nick.read@manchester.ac.uk.
authors.forename: Nick D
authors.initials: ND
authors.lastname: Read
authors.affiliation: Microbiology and Kluyver Center for Genomics of Industrial Fermentation, Utrecht University, Padualaan 8, 3584 CH Utrecht, The Netherlands. Electronic address: h.a.b.wosten@uu.nl.
authors.forename: Han A B
authors.initials: HA
authors.lastname: Wösten
mesh_terms: D001234:Aspergillus niger / Q000502:physiology*; D001692:Biological Transport; D002462:Cell Membrane / Q000378:metabolism*; D002473:Cell Wall / Q000378:metabolism*; D015870:Gene Expression; D017930:Genes, Reporter; D005838:Genotype; D005947:Glucose / Q000378:metabolism; D025301:Hyphae / Q000502:physiology*; D042541:Intracellular Space / Q000378:metabolism
chemical_list: D005947:Glucose
keywords: Fungus; Glucose; Heterogeneity; Mycelium; Septa; Transport