A developmentally controlled cellular decompartmentalization process executes programmed cell death in the Arabidopsis root cap.
Plant Cell
; 36(4): 941-962, 2024 Mar 29.
Article
in En
| MEDLINE
| ID: mdl-38085063
ABSTRACT
Programmed cell death (PCD) is a fundamental cellular process crucial to development, homeostasis, and immunity in multicellular eukaryotes. In contrast to our knowledge on the regulation of diverse animal cell death subroutines, information on execution of PCD in plants remains fragmentary. Here, we make use of the accessibility of the Arabidopsis (Arabidopsis thaliana) root cap to visualize the execution process of developmentally controlled PCD. We identify a succession of selective decompartmentalization events and ion fluxes as part of the terminal differentiation program that is orchestrated by the NO APICAL MERISTEM, ARABIDOPSIS THALIANA ACTIVATING FACTOR, CUP-SHAPED COTYLEDON (NAC) transcription factor SOMBRERO. Surprisingly, the breakdown of the large central vacuole is a relatively late and variable event, preceded by an increase of intracellular calcium levels and acidification, release of mitochondrial matrix proteins, leakage of nuclear and endoplasmic reticulum lumina, and release of fluorescent membrane reporters into the cytosol. In analogy to animal apoptosis, the plasma membrane remains impermeable for proteins during and after PCD execution. Elevated intracellular calcium levels and acidification are sufficient to trigger cell death execution specifically in terminally differentiated root cap cells, suggesting that these ion fluxes act as PCD-triggering signals. This detailed information on the cellular processes occurring during developmental PCD in plants is a pivotal prerequisite for future research into the molecular mechanisms of cell death execution.
Full text:
1
Collection:
01-internacional
Database:
MEDLINE
Main subject:
Arabidopsis
/
Arabidopsis Proteins
Language:
En
Journal:
Plant Cell
Journal subject:
BOTANICA
Year:
2024
Document type:
Article
Affiliation country:
Belgium