Chloroplast Degradation: Multiple Routes Into the Vacuole

Chloroplasts provide energy for all plants by producing sugar during photosynthesis. To adapt to various environmental and developmental cues, plants have developed specific strategies to control chloroplast homeostasis in plant cells, including chloroplast degradation during leaf senescence and the transition of chloroplasts into other types of plastids during the day-night cycle. In recent years, autophagy has emerged as an essential mechanism for selective degradation of chloroplast materials (also known as chlorophagy) in the vacuole. Different types of membrane structures have been implicated to involve in the delivery of distinct chloroplast contents. Here we provide a current overview on chlorophagy and discuss the possible chloroplast receptors and upstream signals in this process

Possible Roles of Membrane Trafficking Components for Lipid Droplet Dynamics in Higher Plants and Green Algae

Lipid droplets are ubiquitous dynamic organelles that contain neutral lipids surrounded by a phospholipid monolayer. They can store and supply lipids for energy metabolism and membrane synthesis. In addition, protein transport and lipid exchange often occur between LDs and various organelles to control lipid homeostasis in response to multiple stress responses and cellular signaling. In recent years, multiple membrane trafficking proteins have been identified through LD proteomics and genetic analyses. These membrane trafficking machineries are emerging as critical regulators to function in different LD-organelle interactions, e.g., for LD dynamics, biogenesis and turnover. In this review, we will summarize recent advances in regard to LD-related membrane trafficking proteins and discuss future investigations in higher plants and green algae

The impact of performance management on employee engagement in China

Abstract Purpose Performance management is crucial for organizations to improve competitive advantages. The increasing number of companies improve their performance management systems to enhance employee engagement, thereby increasing organizational performance. The aim of this paper is to explore the relationship between performance management and employee engagement in China. Methodology This study adopted quantitative research methods, selected 208 employees from all walks of life in China as samples and conducted surveys through online questionnaires. Then, use correlation and regression analysis to analyze the relationship between the three main steps of performance management (performance appraisal, performance feedback, and reward) and employee engagement. Findings The study findings show that there is a significant positive correlation between the three main steps of performance management (performance appraisal, performance feedback, and reward) and employee engagement. It was also found that rewards had the greatest impact on employee engagement. Research limitations The research did not focus on a certain industry, and the research results may change due to different industries. Originality/value Different from the previous literature, this paper studies the impact of the three main steps of performance management (performance appraisal, performance feedback, and reward) on employee engagement in the context of China and compares the impact of these three steps

ROS/TRPA1/CGRP signaling mediates cortical spreading depression

Abstract Objectives The transient receptor potential ankyrin A 1 (TRPA1) channel and calcitonin gene-related peptide (CGRP) are targets for migraine prophylaxis. This study aimed to understand their mechanisms in migraine by investigating the role of TRPA1 in cortical spreading depression (CSD) in vivo and exploring how reactive oxygen species (ROS)/TRPA1/CGRP interplay in regulating cortical susceptibility to CSD. Methods Immunohistochemistry was used for detecting TRPA1 expression. CSD was induced by K+ on the cerebral cortex, monitored using electrophysiology in rats, and intrinsic optical imaging in mouse brain slices, respectively. Drugs were perfused into contralateral ventricle of rats. Lipid peroxidation (malondialdehyde, MDA) analysis was used for indicating ROS level. Results TRPA1 was expressed in cortical neurons and astrocytes of rats and mice. TRPA1 deactivation by an anti-TRPA1 antibody reduced cortical susceptibility to CSD in rats and decreased ipsilateral MDA level induced by CSD. In mouse brain slices, H2O2 facilitated submaximal CSD induction, which disappeared by the antioxidant, tempol and the TRPA1 antagonist, A-967079; Consistently, TRPA1 activation reversed prolonged CSD latency and reduced magnitude by the antioxidant. Further, blockade of CGRP prolonged CSD latency, which was reversed by H2O2 and the TRPA1 agonist, allyl-isothiocyanate, respectively. Conclusions ROS/TRPA1/CGRP signaling plays a critical role in regulating cortical susceptibility to CSD. Inhibition ROS and deactivation of TRPA1 channels may have therapeutic benefits in preventing stress-triggered migraine via CGRP

The Multivesicular Body and Autophagosome Pathways in Plants

In eukaryotic cells, the endomembrane system consists of multiple membrane-bound organelles, which play essential roles in the precise transportation of various cargo proteins. In plant cells, vacuoles are regarded as the terminus of catabolic pathways whereas the selection and transport of vacuolar cargoes are mainly mediated by two types of organelles, multivesicular bodies (MVBs) also termed prevacuolar compartments (PVCs) and autophagosomes. MVBs are single-membrane bound organelles with intraluminal vesicles and mediate the transport between the trans-Golgi network (TGN) and vacuoles, while autophagosomes are double-membrane bound organelles, which mediate cargo delivery to the vacuole for degradation and recycling during autophagy. Great progress has been achieved recently in identification and characterization of the conserved and plant-unique regulators involved in the MVB and autophagosome pathways. In this review, we present an update on the current knowledge of these key regulators and pay special attention to their conserved protein domains. In addition, we discuss the possible interplay between the MVB and autophagosome pathways in regulating vacuolar degradation in plants

Research on institutional contradiction and legitimacy crisis of internet car-hailing platform with the Grounded Theory

Based on the case of DiDi travel platform event, we used the grounded theory to analyze the legitimacy crisis occurrence mechanism of internet car-hailing platforms organizational field. We found that, the institutional contradiction between public welfare logic and profit logic in the process of DiDi’s Institutional Entrepreneurship leads to the legitimacy crisis; the crisis event causes the government\u27s supervision, media attention and consumer resistance, which ultimately leads to the deterioration and spillover of legitimacy crisis from DiDi to the whole internet car-hailing platforms organizational field