Desmosome dualism: most of the junction is stable but a plakophilin moiety is persistently dynamic.

Research output: Contribution to journalArticlepeer-review

  • External authors:
  • Judith B. Fülle
  • Henri Huppert
  • David Liebl
  • Jaron Liu
  • Rogerio Alves de Almeida
  • Bian Yanes
  • Graham D. Wright
  • E Birgitte Lane
  • David Garrod

Abstract

Desmosomes, strong cell-cell junctions of epithelia and cardiac muscle, link intermediate filaments to cell membranes and mechanically integrate cells across tissues, dissipating mechanical stress. They comprise five major protein classes – desmocollins and desmogleins (the desmosomal cadherins), plakoglobin, plakophilins and desmoplakin - whose individual contribution to the structure and turnover of desmosomes is poorly understood. Using live-cell imaging together with FRAP and FLAP we show that desmosomes consist of two contrasting protein moieties or modules: a very stable moiety of desmosomal cadherins, desmoplakin and plakoglobin, and a highly mobile plakophilin (Pkp2a). As desmosomes mature from calcium-dependence to calcium-independent hyper-adhesion, their stability increases, but Pkp2a remains highly mobile. We show that desmosome down-regulation during growth factor-induced cell scattering proceeds by internalisation of whole desmosomes, which still retain a stable moiety and highly mobile Pkp2a. This molecular mobility of Pkp2a suggests a transient and probably regulatory role for Pkp2a in desmosomes.

Bibliographical metadata

Original languageEnglish
JournalJournal of Cell Science
Publication statusAccepted/In press - 5 Oct 2021