hex-1, a Gene Unique to Filamentous Fungi, Encodes the Major Protein of the Woronin Body and Functions as a Plug for Septal Pores

We have identified a gene, named hex-1, that encodes the major protein in the hexagonal crystals, or Woronin bodies, of Neurospora crassa. Analysis of a strain with a null mutation in the hex-1 gene showed that the septal pores in this organism were not plugged when hyphae were damaged, leading to e...

Full description

Saved in:
Bibliographic Details
Published in:Fungal genetics and biology 2000-12, Vol.31 (3), p.205-217
Main Authors: Tenney, Karen, Hunt, Ian, Sweigard, James, Pounder, June I., McClain, Chadonna, Bowman, Emma Jean, Bowman, Barry J.
Format: Article
Language:English
Subjects:
Amino Acid Sequence
Base Sequence
Blotting, Western
catalase
Catalase - chemistry
Cloning, Molecular
Electrophoresis, Polyacrylamide Gel
filamentous growth
Fungal Proteins - chemistry
Fungal Proteins - genetics
Genes, Fungal
hexagonal crystals
hyphal tips
Molecular Sequence Data
Molecular Weight
Mutation
Neurospora crassa - genetics
Organelles - chemistry
Organelles - genetics
peroxisome
SDS-resistant protein
Sequence Alignment
Citations: Items that this one cites
Items that cite this one
Online Access:Get full text
Tags: Add Tag
No Tags, Be the first to tag this record!
Description
Summary:We have identified a gene, named hex-1, that encodes the major protein in the hexagonal crystals, or Woronin bodies, of Neurospora crassa. Analysis of a strain with a null mutation in the hex-1 gene showed that the septal pores in this organism were not plugged when hyphae were damaged, leading to extensive loss of cytoplasm. When grown on agar plates containing sorbose, the hex-1− strain showed extensive lysis of hyphal tips. The HEX-1 protein was predicted to be 19,125 Da. Analysis of the N-terminus of the purified protein indicated that 16 residues are cleaved, yielding a protein of 17,377 Da. A polyclonal antibody raised to the HEX-1 protein recognized multiple forms of the protein, apparently dimers and tetramers that were resistant to solubilization by sodium dodecyl sulfate and reducing reagents. Treatment of the protein with phosphatase caused dissociation of these oligomers. Preparations enriched in Woronin bodies contained catalase activity, which was not detected in comparable fractions from the hex-1− mutant strain. These results support the hypothesis that the Woronin body is a specialized peroxisome that functions as a plug for septal pores.
ISSN:1087-1845
1096-0937
DOI:10.1006/fgbi.2000.1230