Artigo
N-rich protein (NRP)-mediated cell death signaling: a new branch of the ER stress response with implications for plant biotechnology
Autor
Reis, Pedro A.B.
Fontes, Elizabeth P.B.
Institución
Resumen
Upon disruption of ER homeostasis, plant cells activate at
least two branches of the unfolded protein response (UPR)
through IRE1-like and ATAF6-like transducers, resulting in the
upregulation of ER-resident molecular chaperones and the
activation of the ER-associated degradation protein system.
Here, we discuss a new ER stress response pathway in plants that
is associated with an osmotic stress response in transducing
a cell death signal. Both ER and osmotic stress induce the
expression of the novel transcription factor GmERD15, which
binds and activates N-rich protein (NRP) promoters to induce
NRP expression and cause the upregulation of GmNAC6, an
effector of the cell death response. In contrast to this activation
mechanism, the ER-resident molecular chaperone binding
protein (BiP) attenuates the propagation of the cell death signal
by modulating the expression and activity of components of
the ER and osmotic stress-induced NRP-mediated cell death
signaling. This interaction attenuates dehydration-induced cell
death and promotes a better adaptation of BiP-overexpressing
transgenic lines to drought.