scholarly journals The role of clathrin in exocytosis and the mutual regulation of endo- and exocytosis in plant cells

2021 ◽  
Author(s):  
Maciek Adamowski ◽  
Ivana Matijević ◽  
Jiří Friml
Keyword(s):  
Regulatory Mechanism ◽  
Plant Cells ◽  
Integral Membrane Protein ◽  
Early Endosome ◽  
Endomembrane System ◽  
Shared Function ◽  
Mutual Regulation ◽  
Golgi Network ◽  
Homeostatic Mechanisms

Within the plant endomembrane system, the vesicle coat protein clathrin localizes to the plasma membrane (PM) and the trans-Golgi Network/Early Endosome (TGN/EE). While the role of clathrin as a major component of endocytosis at the PM is well established, its function at TGN/EE, possibly in exocytosis or the vacuolar pathway, is a matter of debate. This shared function of clathrin also opens a question whether plant cells possess a homeostatic mechanisms that balance rates of opposite trafficking routes, such as endo- and exocytosis. Here we address these questions using lines inducibly silencing CLATHRIN HEAVY CHAIN (CHC). We find a relocation of exocytic soluble and integral membrane protein cargoes to the vacuole, supporting a function of clathrin in exocytosis. A comparison with lines overexpressing AUXILIN-LIKE1, where inhibition of CME precedes rerouting of secretory cargoes, does not support a homeostatic regulatory mechanism adjusting exocytosis to the rates of endocytosis. Complementary experiments reveal only minor and variably detectable reductions in the rates of CME in secretory mutants, also not indicative of a converse homeostatic mechanism adjusting rates of endocytosis to the rates of secretion.

BFA-induced compartments from the Golgi apparatus and trans-Golgi network/early endosome are distinct in plant cells

2009 ◽  
Vol 60 (5) ◽  
pp. 865-881 ◽  
Author(s):  
Sheung Kwan Lam ◽  
Yi Cai ◽  
Yu Chung Tse ◽  
Juan Wang ◽  
Angus Ho Yin Law ◽  
...  
Keyword(s):  
Golgi Apparatus ◽  
Plant Cells ◽  
Early Endosome ◽  
Trans Golgi Network ◽  
Golgi Network

scholarly journals The role of the AP-1 adaptor complex in trafficking between the trans-Golgi Network and endosomal system

2005 ◽  
Author(s):  
◽  
Christopher Foote
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Early Endosome ◽  
Trans Golgi Network ◽  
Retrieval Mechanism ◽  
Prevacuolar Compartment ◽  
Golgi Network ◽  
In Transit ◽  
Endosomal System ◽  
Kinetics Of

In Saccharomyces cerevisiae it is generally accepted that there are two routes for trafficking of proteins from the trans-Golgi network (TGN) to the vacuole. One involves direct transport from the TGN to the vacuole. The second involves transport from the TGN to the prevacuolar compartment (PVC) via GGA coated vesicles, followed by PVC to vacuole transport. We propose that there is a third route. This route entails transit from the TGN to the early endosome (EE), followed by delivery to the PVC and vacuole. In support of an alternative route, the processing kinetics of A(F[arrow]A)-ALP are not affected by mutations in the GGA proteins. This is in contrast to proteins that use the GGA pathway, as their delivery to the vacuole is significantly slowed when GGA function is ablated. Further support of an EE itinerary is the observation that A(F[arrow]A)-ALP co localizes with the lipophilic dye, FM4-64 at a time when the dye is associated with the EE. Disruption of the AP-1 vesicle coat complex leads to an accelerated processing of A(F[arrow]A)-ALP. Appending the region of A(F[arrow]A)-ALP that interacts with AP-1 to Cps1p delays its progress to the vacuole. These results are consistent with a model in which A(F[arrow]A)-ALP passes through the EE in transit to the vacuole. A(F[arrow]A)-ALP physically interacts with AP-1, and this interaction delays its delivery to the vacuole. Data presented in this thesis suggests that in Saccharomyces cerevisiae AP-1 functions as a retrieval mechanism from the EE to the TGN.

scholarly journals Topoisomerase II is regulated by translationally controlled tumor protein for cell survival during organ growth in Drosophila

2021 ◽  
Vol 12 (9) ◽  
Author(s):  
Dae-Wook Yang ◽  
Jung-Wan Mok ◽  
Stephanie B. Telerman ◽  
Robert Amson ◽  
Adam Telerman ◽  
...  
Keyword(s):  
Cell Survival ◽  
Topoisomerase Ii ◽  
Wing Disc ◽  
Organ Development ◽  
Translationally Controlled Tumor Protein ◽  
Protein Levels ◽  
Eye Disc ◽  
Mutual Regulation

AbstractRegulation of cell survival is critical for organ development. Translationally controlled tumor protein (TCTP) is a conserved protein family implicated in the control of cell survival during normal development and tumorigenesis. Previously, we have identified a human Topoisomerase II (TOP2) as a TCTP partner, but its role in vivo has been unknown. To determine the significance of this interaction, we examined their roles in developing Drosophila organs. Top2 RNAi in the wing disc leads to tissue reduction and caspase activation, indicating the essential role of Top2 for cell survival. Top2 RNAi in the eye disc also causes loss of eye and head tissues. Tctp RNAi enhances the phenotypes of Top2 RNAi. The depletion of Tctp reduces Top2 levels in the wing disc and vice versa. Wing size is reduced by Top2 overexpression, implying that proper regulation of Top2 level is important for normal organ development. The wing phenotype of Tctp RNAi is partially suppressed by Top2 overexpression. This study suggests that mutual regulation of Tctp and Top2 protein levels is critical for cell survival during organ development.

scholarly journals Functions of Dendritic Cells and Its Association with Intestinal Diseases

Cells ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 583
Author(s):  
Ze-Jun Yang ◽  
Bo-Ya Wang ◽  
Tian-Tian Wang ◽  
Fei-Fei Wang ◽  
Yue-Xin Guo ◽  
...  
Keyword(s):  
Inflammatory Bowel Disease ◽  
Dendritic Cells ◽  
Immune System ◽  
Regulatory Mechanism ◽  
Intestinal Tumors ◽  
Regulatory Relationship ◽  
Intestinal Diseases ◽  
Inflammatory Bowel ◽  
Plasmacytoid Dcs

Dendritic cells (DCs), including conventional DCs (cDCs) and plasmacytoid DCs (pDCs), serve as the sentinel cells of the immune system and are responsible for presenting antigen information. Moreover, the role of DCs derived from monocytes (moDCs) in the development of inflammation has been emphasized. Several studies have shown that the function of DCs can be influenced by gut microbes including gut bacteria and viruses. Abnormal changes/reactions in intestinal DCs are potentially associated with diseases such as inflammatory bowel disease (IBD) and intestinal tumors, allowing DCs to be a new target for the treatment of these diseases. In this review, we summarized the physiological functions of DCs in the intestinal micro-environment, their regulatory relationship with intestinal microorganisms and their regulatory mechanism in intestinal diseases.

scholarly journals Nanobiotechnology for Agriculture: Smart Technology for Combating Nutrient Deficiencies with Nanotoxicity Challenges

2021 ◽  
Vol 13 (4) ◽  
pp. 1781
Author(s):  
Gaurav Chugh ◽  
Kadambot H. M. Siddique ◽  
Zakaria M. Solaiman
Keyword(s):  
Targeted Delivery ◽  
Plant Cells ◽  
Agricultural Practices ◽  
Nutrient Deficiencies ◽  
Holistic View ◽  
Synthesis Of Nanoparticles ◽  
Toxicity Potential ◽  
Stimulate Plant Growth ◽  
Sustainable Agricultural Practices

Nanobiotechnology in agriculture is a driver for modern-day smart, efficient agricultural practices. Nanoparticles have been shown to stimulate plant growth and disease resistance. The goal of sustainable farming can be accomplished by developing and sustainably exploiting the fruits of nanobiotechnology to balance the advantages nanotechnology provides in tackling environmental challenges. This review aims to advance our understanding of nanobiotechnology in relevant areas, encourage interactions within the research community for broader application, and benefit society through innovation to realize sustainable agricultural practices. This review critically evaluates what is and is not known in the domain of nano-enabled agriculture. It provides a holistic view of the role of nanobiotechnology in multiple facets of agriculture, from the synthesis of nanoparticles to controlled and targeted delivery, uptake, translocation, recognition, interaction with plant cells, and the toxicity potential of nanoparticle complexes when presented to plant cells.

scholarly journals Viroids as a Tool to Study RNA-Directed DNA Methylation in Plants

Cells ◽  
2021 ◽  
Vol 10 (5) ◽  
pp. 1187
Author(s):  
Michael Wassenegger ◽  
Athanasios Dalakouras
Keyword(s):  
Dna Methylation ◽  
Rna Interference ◽  
Gene Silencing ◽  
Plant Cells ◽  
Transcriptional Gene Silencing ◽  
Rnai Machinery ◽  
Double Stranded Rna ◽  
Post Transcriptional Gene Silencing ◽  
Cumulative Amount

Viroids are plant pathogenic, circular, non-coding, single-stranded RNAs (ssRNAs). Members of the Pospiviroidae family replicate in the nucleus of plant cells through double-stranded RNA (dsRNA) intermediates, thus triggering the host’s RNA interference (RNAi) machinery. In plants, the two RNAi pillars are Post-Transcriptional Gene Silencing (PTGS) and RNA-directed DNA Methylation (RdDM), and the latter has the potential to trigger Transcriptional Gene Silencing (TGS). Over the last three decades, the employment of viroid-based systems has immensely contributed to our understanding of both of these RNAi facets. In this review, we highlight the role of Pospiviroidae in the discovery of RdDM, expound the gradual elucidation through the years of the diverse array of RdDM’s mechanistic details and propose a revised RdDM model based on the cumulative amount of evidence from viroid and non-viroid systems.

Adaptations in the Muscle Cell to Training: Role of the Na+-K+-Atpase

2000 ◽  
Vol 25 (3) ◽  
pp. 204-216 ◽  
Author(s):  
Howard J. Green
Keyword(s):  
Metabolic Flux ◽  
Contractile Activity ◽  
Integral Membrane Protein ◽  
Adaptive Responses ◽  
Muscle Strain ◽  
Muscle Contractility ◽  
Exercise Adaptation ◽  
Altered Regulation ◽  
Key Words Muscle

The plasticity of skeletal muscle is evident following the onset of regular contractile activity where extensive adaptations can be observed at all levels of organization. Among the properties subject to altered regulation is the Na+-K+-ATPase, an integral membrane protein distributed throughout the sarcolemma and t-tubule, which functions to maintain high Na+ and K+ transmembrane gradients. This protein is uniquely positioned to control muscle excitation and contraction processes, metabolic flux rates, and contractility. Pronounced and rapid upregulation in the Na+-K+-ATPase content can be observed within the first days of exercise and well before the other major ATPase proteins involved in Ca2+ and actomyosin cycling. Moreover, the Na+-K+-ATPase is subject to complex messenger regulation, involved both in the accommodation and the adaptive responses to contractile activity. This emphasizes that adaptive responses can be mediated soon after the onset of training and may have profound affects on muscle contractility and other cellular adaptations. Key Words: muscle, strain, exercise, adaptation, accommodation

THE ROLE OF THE GILL FILAMENT MUSCULATURE IN TELEOSTS

1962 ◽  
Vol 40 (5) ◽  
pp. 785-802 ◽  
Author(s):  
Valerie M. Pasztor ◽  
H. Kleerekoper
Keyword(s):  
Connective Tissue ◽  
Regulatory Mechanism ◽  
Gill Filament ◽  
Gill Arch ◽  
Breathing Cycle ◽  
Adequate Ventilation ◽  
Oral Surface ◽  
Freshwater Teleosts

The gill filament musculature of several freshwater teleosts was studied using visual and oscillographic methods. Continual activity was observed in the small muscles connecting the two hemibranch rows on each gill arch in all the fish examined. In those fish where the gill filament rows are bound together by a sheet of connective tissue, there was an additional active series of muscles situated on the oral surface of each gill arch. Both series of muscles contracted once every breathing cycle whether the fish was in water or in air.It is proposed that these muscles have two important functions. Firstly, they assist in maintaining an even spacing of the gill hemibranchs at all phases of the breathing cycle, thus insuring that all the lamellae receive adequate ventilation. Secondly, they take part in a regulatory mechanism which controls the amount of water which will be presented to the respiratory surfaces of the lamellae.

Sign in / Sign up

Export Citation Format

Share Document