Three-dimensional image analysis of plugging at the septal pore by Woronin body during hypotonic shock inducing hyphal tip bursting in the filamentous fungus Aspergillus oryzae.
We observed that the filamentous fungus, Aspergillus oryzae, grown on agar media burst out cytoplasmic constituents from the hyphal tip soon after flooding with water. Woronin body is a specialized organelle known to plug the septal pore adjacent to the lysed compartment to prevent extensive loss of cytoplasm. A. oryzae Aohex1 gene homologous to Neurospora crassa HEX1 gene encoding a major protein in Woronin body was expressed as a fusion with DsRed2, resulting in visualization of Woronin body. Confocal microscopy and three-dimensional reconstruction of images visualized the septal pore as a dark region surrounded by green fluorescence of EGFP-fused secretory protein, RNase T1, on the septum. Dual fluorescent labeling revealed the plugging of the septal pores adjacent to the lysed apical compartments by Woronin bodies during hypotonic shock. Disruption of Aohex1 gene caused disappearance of Woronin bodies and the defect to prevent extensive loss of cytoplasm during hypotonic shock.
Maruyama
Jun-ichi
J
Department of Biotechnology, University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan.
Juvvadi
Praveen Rao
PR
Ishi
Kazutomo
K
Kitamoto
Katsuhiko
K
D001236:Aspergillus oryzae / Q000235:genetics / Q000502:physiology* / Q000648:ultrastructure; D001483:Base Sequence; D003001:Cloning, Molecular; D017931:DNA Primers; D005456:Fluorescent Dyes; D005800:Genes, Fungal; D018613:Microscopy, Confocal
D017931:DNA Primers; D005456:Fluorescent Dyes