Woronin body-based sealing of septal pores

Highlights

• •

  Upon wounding, Woronin bodies seal hyphal septa in filamentous ascomycetes.

• •

  Little is known about the mechanism underpinning Woronin body translocation.

• •

  Passive bulk flow of cytoplasm may move Woronin bodies into the septal pore.

• •

  Mechanisms that involve Lah proteins are likely to support Woronin body based sealing.

• •

  ATP is required to prevent Woronin bodies from closing pores in healthy cells.

Abstract

In ascomycete fungi, hyphal cells are separated by perforate septa, which allow cell-to-cell communication. To protect against extensive wound-induced damage, septal pores are sealed by peroxisome-derived Woronin bodies (WBs). The mechanism underpinning WB movement is unknown, but cytoplasmic bulk flow may “flush” WBs into the pore. However, some studies suggest a controlled and active mechanism of WB movement. Indeed, in the wheat pathogen Zymoseptoria tritici cellular ATP prevents WBs from pore sealing in unwounded cells. Thus, cells appear to exert active control over WB closure. Here, we summarize our current understanding of WB-based pore sealing in ascomycete fungi.