Vacuolar processing enzyme translocates to the vacuole through the autophagy pathway to induce programmed cell death.

Vacuolar processing enzyme translocates to the vacuole through the autophagy pathway to induce programmed cell death.
Autophagy. 2020 Nov 29;:
Authors: Teper-Bamnolker P, Danieli R, Peled-Zehavi H, Belausov E, Abu-Abied M, Avin-Wittenberg T, Sadot E, Eshel D
Abstract
The caspase-like vacuolar processing enzyme (VPE) is a key factor in programmed cell death (PCD) associated with plant stress responses. Growth medium lacking a carbon source and dark conditions caused punctate labeling of 35S::VPE1-GFP (StVPE1-GFP) in potato leaves. Under conditions of carbon starvation, VPE activity and PCD symptoms strongly increased in BY-2 cells, but to a much lesser extent in VPE-RNAi BY-2 cells. During extended exposure to carbon starvation, VPE expression and activity levels peaked, with a gradual increase in BY-2 cell death. Histological analysis of StVPE1-GFP in BY-2 cells showed that carbon starvation induces its translocation from the endoplasmic reticulum to the central vacuole through tonoplast engulfment. Exposure of BY-2 culture to the macroautophagy/autophagy inhibitor concanamycin A led to, along with an accumulation of autophagic bodies, accumulation of StVPE1-GFP in the cell vacuole. This accumulation did not occur in the presence of 3-methyladenine, an inhibitor of early-stage autophagy. BY-2 cells constitutively expressing RFP-StATG8IL, an autophagosome marker, showed colocalization with the StVPE1-GFP protein in the cytoplasm and v...

Source: Autophagy - November 29, 2020 Category: Cytology Authors: Teper-Bamnolker P, Danieli R, Peled-Zehavi H, Belausov E, Abu-Abied M, Avin-Wittenberg T, Sadot E, Eshel D Tags: Autophagy Source Type: research