uptake pathway
Recently Published Documents


TOTAL DOCUMENTS

128
(FIVE YEARS 33)

H-INDEX

34
(FIVE YEARS 5)

Geoderma ◽  
2021 ◽  
Vol 403 ◽  
pp. 115261
Author(s):  
Lin Zhang ◽  
Qun Chu ◽  
Jianwei Zhou ◽  
Zed Rengel ◽  
Gu Feng

Author(s):  
Prasanna M. Bhogale ◽  
Robin A. Sorg ◽  
Jan-Willem Veening ◽  
Johannes Berg

2021 ◽  
Vol 12 (1) ◽  
Author(s):  
Syamantak Khan ◽  
June Ho Shin ◽  
Valentina Ferri ◽  
Ning Cheng ◽  
Julia E. Noel ◽  
...  

AbstractTumor organoids offer new opportunities for translational cancer research, but unlike animal models, their broader use is hindered by the lack of clinically relevant imaging endpoints. Here, we present a positron-emission microscopy method for imaging clinical radiotracers in patient-derived tumor organoids with spatial resolution 100-fold better than clinical positron emission tomography (PET). Using this method, we quantify 18F-fluorodeoxyglucose influx to show that patient-derived tumor organoids recapitulate the glycolytic activity of the tumor of origin, and thus, could be used to predict therapeutic response in vitro. Similarly, we measure sodium-iodine symporter activity using 99mTc- pertechnetate and find that the iodine uptake pathway is functionally conserved in organoids derived from thyroid carcinomas. In conclusion, organoids can be imaged using clinical radiotracers, which opens new possibilities for identifying promising drug candidates and radiotracers, personalizing treatment regimens, and incorporating clinical imaging biomarkers in organoid-based co-clinical trials.


Energies ◽  
2021 ◽  
Vol 14 (16) ◽  
pp. 5015
Author(s):  
Mohammad Alipour ◽  
Rodney A. Stewart ◽  
Oz Sahin

Understanding the residential adoption decision of battery energy storage systems (BESSs) is central to the implementation of successful intervention policies. However, when the residential solar photovoltaics (PV) becomes a widely accepted technology across a society, accurately modelling the behaviour shows a higher degree of complexity. In this vein, the uptake pathway of BESS and PV coupled with BESS (PV–BESS) would predictably exhibit similar attitudinal traits to that of PV consumption. This notion implies that the antecedent PV decision can be regarded as the past behaviour of the BESS adopter by creating attitudinal implications. The PV use status also yields a higher degree of heterogeneity through the emergence of four new household groups and the inherent imbalances in the involvement of the interwoven financial, technical, sociodemographic, and psychological predictors. This perspective employs the Reasoned Action Approach (RAA) to allegorise a decision-making model of BESS and PV–BESS adoption behaviour in a mature PV market (Australia). It argues that the particularised background factors will likely shape the individual’s attitudes and perceived norms for intention, and showcases affordability and the use of PV as the two control components that dictate the final decision.


Author(s):  
David A. Phoenix ◽  
Frederick Harris ◽  
Sarah R. Dennison

: A number of disorders and diseases are associated with conditions of high pH and many conventional antibiotics lose their efficacy under these pH conditions, generating a need for novel antimicrobials, and a potential solution to fulfil this need is antimicrobial peptides (AMPs) with high pH optima. This review shows that a variety of anionic and cationic AMPs with this pH dependency are produced by creatures across the eukaryotic kingdom, including humans, rabbits, cattle, sheep, fish and frogs. These AMPs exhibit activity against viruses, bacteria and fungi that involves membrane interactions and appear to be facilitated by a variety of mechanisms that generally promote passage across membranes to attack intracellular targets, such as DNA or protein synthesis, and / or membrane lysis. Some of these mechanisms are unknown but those elucidated include the use of bacterial pores and transporters, the self-promoted uptake pathway and established models of membrane interaction, such as the carpet mechanism, toroidal pore formation, the adoption of tilted peptide and the SHM model. A variety of potential roles have been proposed for these AMPs, including use as antivirals, antibacterials, antifungals, adjuvants to antimicrobial therapy, biomarkers of disease and probes for pathogenic microbes. In this review, these properties are described and discussed, with an emphasis on the antimicrobial mechanisms used by these AMPs and the pH dependency of these mechanisms.


Author(s):  
Xiaoyu Shi ◽  
Meng Wei ◽  
Zihao Xu ◽  
Ying Liu ◽  
Mujia Zhang ◽  
...  

During the Plasmodium erythrocytic cycle, glucose is taken up by glucose transporters (GLUTs) in red blood cells (RBCs) and supplied to parasites via the Plasmodium hexose transporter. Here, we demonstrate that the glucose uptake pathway in infected RBCs (iRBCs) can be hijacked by vitamin C (Vc). GLUTs preferentially transport the oxidized form of Vc, which is subsequently reduced in the cytosol. Vc, which is expected to burden the intracellular reducing capacity, inhibits Plasmodium berghei and Plasmodium falciparum growth. Vc uptake is drastically increased in iRBCs, with a large proportion entering parasites. Increased absorption of Vc causes accumulation of reactive oxygen species, reduced ATP production, and elevated eryptosis in iRBCs and apoptosis in parasites. The level of oxidative stress induced by Vc is significantly higher in iRBCs than uninfected RBCs, not seen in chloroquine or artemisinin-treated iRBCs, and effective in inhibiting chloroquine or artemisinin-resistant parasites. These findings provide important insights into the drug sensitivity of Plasmodium.


Author(s):  
Mayumi Arai ◽  
Hisakazu Komori ◽  
Daichi Fujita ◽  
Ikumi Tamai

2021 ◽  
Author(s):  
Ran Erel ◽  
Sudeep Tiwari ◽  
Ilana Shtein ◽  
Avner Gross

<p>Phosphorus (P) limitation is prevalent around the world,<sup></sup>primarily because most soil P have low bioavailability. In P poor ecosystems, deposition of P-rich desert dust is recognized as a major component of the P cycle. The acknowledged paradigm is that plants acquire P deposited in soil primarily via their roots. We tested whether, and to what extent, plants acquire P directly from dust deposited on their leaves and what are the underlining uptake mechanisms of insoluble P. P-rich dust was applied to P sufficient and P deficient chickpea, maize and wheat plants and was compared to plants which received inert silica powder. Foliar application of dust doubled the growth of P stressed chickpea and wheat, two crops originating near the Syrian Desert. P deficiency enhanced the acquisition of insoluble P through series of leaf modifications that increased foliar dust capture, acidified the leaf surface and, in chickpea, enhanced exudation of P-solubilizing organic acids. In in-situ trials, we demonstrated that the modifications of leaf pH and exudation of oxalic and malic acids substantially promoted P solubilisation from dust.  Foliar responses did not occur in maize and in P sufficient plants which displayed only a marginal response to dust. Our results demonstrate that foliar uptake of P from dust can be an alternative P acquisition pathway in P-deficient plants. Interestingly, the abovementioned foliar responses are comparable to known P uptake root responses. Given that P limitation is almost universal, foliar P uptake pathway will have significant ecological and agricultural implications.</p>


Cells ◽  
2021 ◽  
Vol 10 (2) ◽  
pp. 451
Author(s):  
Markus Mukenhirn ◽  
Francesco Muraca ◽  
Delia Bucher ◽  
Edgar Asberger ◽  
Elisa Cappio Barazzone ◽  
...  

One of the most fundamental processes of the cell is the uptake of molecules from the surrounding environment. Clathrin-mediated endocytosis (CME) is the best-described uptake pathway and regulates nutrient uptake, protein and lipid turnover at the plasma membrane (PM), cell signaling, cell motility and cell polarity. The main protein in CME is clathrin, which assembles as a triskelion-looking building block made of three clathrin heavy chains and three clathrin light chains. Compared to clathrin heavy chains (CHCs), the role of the two isoforms of clathrin light chains (CLCA and CLCB) is poorly understood. Here, we confirm that the simultaneous deletion of both CLCA/B causes abnormal actin structures at the ventral PM and we describe them, for the first time, as functional invadopodia rather than disorganized actin-cytoskeleton assembly sites. Their identification is based on the occurrence of common invadopodia markers as well as functional invadopodia activity characterized by an increased local proteolytic activity of the extracellular matrix proteins. We demonstrate that CLCA/B deletion impacts the intracellular trafficking and recovery of the matrix metalloproteinase 14 (MMP14) leading to its accumulation at the plasma membrane and induction of invadopodia formation. Importantly, we show that invadopodia formation can be prevented by depletion of MMP14. As such, we propose that CLCA/B regulate invadopodia formation by regulating MMP14 delivery to the plasma membrane.


Author(s):  
Jianhua Yin ◽  
Mengdan Ding ◽  
Fanglan Zha ◽  
Jiadi Zhang ◽  
Qiu Meng ◽  
...  

Prodiginines are a family of red-pigmented secondary metabolites with multiple biological activities. The biosynthesis of prodiginines is affected by various physiological and environmental factors. Thus its regulation is highly complex and multifaceted. Although the regulatory mechanism for prodiginine biosynthesis has been extensively studied in Serratia and Streptomyces species, little is known about that in the marine β-proteobacteria, Pseudoalteromonas species. In this study, we report that stringent starvation protein A (SspA), an RNA polymerase-associated regulatory protein, is required for the biosynthesis of prodiginine in Pseudoalteromonas sp. R3. The strain lacking sspA (ΔsspA) fails to produce prodiginine, which is resulted from the downregulation of the prodiginine biosynthetic gene (pig) cluster. The effect of SspA on prodiginine biosynthesis is independent of histone-like nucleoid structuring protein (H-NS) and RpoS (σS). Further analysis demonstrates that the ΔsspA strain has a significant decrease in the transcription of siderophore biosynthesis gene (pvd) cluster, leading to the inhibition of siderophore production and iron uptake. The ΔsspA strain regains the ability to synthesize prodiginine by co-cultivation with siderophore producers or the addition of iron. Therefore, we conclude that SspA-regulated prodiginine biosynthesis is due to decreased siderophore levels and iron deficiency. We further show that the iron homeostasis master regulator Fur is also essential for pig transcription and prodiginine biosynthesis. Overall, our results suggest that SspA indirectly regulates the biosynthesis of prodiginine, which is mediated by the siderophore-dependent iron uptake pathway. IMPORTANCE The red-pigmented prodiginines are attracting increasing interest due to their broad biological activities. As with many secondary metabolites, the biosynthesis of prodiginines is regulated by both environmental and physiological factors. At present, studies on the regulation of prodiginine biosynthesis are mainly restricted to Serratia and Streptomyces species. This work focused on the regulatory mechanism of prodiginine biosynthesis in Pseudoalteromonas sp. R3. We found that stringent starvation protein A (SspA) positively regulates prodiginine biosynthesis via affecting the siderophore-dependent iron uptake pathway. The connections among SspA, iron homeostasis and prodiginine biosynthesis were investigated. These findings uncover a novel regulatory mechanism for prodigiosin biosynthesis.


Sign in / Sign up

Export Citation Format

Share Document