Progenitor-like cells contributing to cellular heterogeneity in the nucleus pulposus are lost in intervertebral disc degeneration.

The nucleus pulposus (NP) in the intervertebral disc (IVD) arises from embryonic notochord. Loss of notochordal-like cells in humans correlates with onset of IVD degeneration, suggesting that they are critical for healthy NP homeostasis and function. Comparative transcriptomic analyses identified expression of progenitor-associated genes (GREM1, KRT18, and TAGLN) in the young mouse and non-degenerated human NP, with TAGLN expression reducing with aging. Lineage tracing using Tagln-CreERt2 mice identified peripherally located proliferative NP (PeriNP) cells in developing and postnatal NP that provide a continuous supply of cells to the entire NP. PeriNP cells were diminished in aged mice and absent in puncture-induced degenerated discs. Single-cell transcriptomes of postnatal Tagln-CreERt2 IVD cells indicate enrichment for TGF-ß signaling in Tagln descendant NP sub-populations. Notochord-specific removal of TGF-ß/BMP mediator Smad4 results in loss of Tagln+ cells and abnormal NP morphologies. We propose Tagln+ PeriNP cells are potential progenitors crucial for NP homeostasis.

CRISPR/Cas9 edited SlGT30 improved both drought resistance and fruit yield through endoreduplication.

There is often a trade-off effect between different agronomic traits due to gene pleiotropy, leading to a negative correlation between yield and resistance. Consequently, using gene-editing techniques to develop superior traits becomes challenging. Genetic resources that defy this constraint are scarce but hold great potential as targets for improvement through the utilisation of CRISPR. Transcription factors are critical in modulating numerous gene expressions across diverse biological processes. Here, we found that the trihelix transcription factor SlGT30 plays a role in drought resistance and tomato fruit development. We edited the SlGT30 gene with CRISPR/Cas9 technology and found that the knockout lines showed decreased stomata density in the leaves and large fruits. Subsequent examination revealed that cell ploidy was impacted in the leaves and fruits of SlGT30 knockout lines. SlGT30 knockout affected cell size through the endoreduplication pathway, manifested in decreased stomata density and reduced water loss. Consequently, this resulted in an enhancement of drought resistance. For the fruit, both cell size and cell number increased in the fruit pericarp of knockout lines, improving the fruit size and weight accordingly. Therefore, SlGT30 represents a promising candidate gene for gene editing in breeding practice.

Nitrogen removal performance of aerobic denitrifying bacteria enhanced by an iron-anode pulsed electric field.

Pulsed electric field (PEF) technology has attracted considerable attention because it can efficiently treat pollutants that are difficult to degrade. In this study, a PEF system using iron as the electrode was constructed to investigate the effect of PEF-Fe on the growth and metabolism of aerobic denitrifying bacteria and the effectiveness of wastewater nitrogen removal. The chemical oxygen demand, NO3--N and nitrate removal rates were 98.93%, 97.60% and 24.40 mg·L-1·h-1, respectively, under optimal conditions. As confirmed in this study, PEF-Fe could improve the key enzyme activities of W207-14. Scanning electron microscopy revealed that the surface of PEF-Fe-treated W207-14 was intact and smooth without any irreversible deformation. Flow cytometry combined with fluorescence staining analysis also confirmed reversible electroporation on the cell membrane surface of PEF-Fe-treated W207-14. Differentially expressed gene enrichment analysis showed that PEF-Fe activated the transmembrane transport function of ATP-binding cassette transporte (ABC) transport proteins and enhanced the cell membrane permeability of aerobic denitrifying bacteria. The significant differential expression of iron-sulphur cluster proteins facilitated the regulation of electron transport and maintenance of the dynamic balance of iron ions within the PEF-Fe system.

CCDC50 promotes tumor growth through regulation of lysosome homeostasis.

The maintenance of lysosome homeostasis is crucial for cell growth. Lysosome-dependent degradation and metabolism sustain tumor cell survival. Here, we demonstrate that CCDC50 serves as a lysophagy receptor, promoting tumor progression and invasion by controlling lysosomal integrity and renewal. CCDC50 monitors lysosomal damage, recognizes galectin-3 and K63-linked polyubiquitination on damaged lysosomes, and specifically targets them for autophagy-dependent degradation. CCDC50 deficiency causes the accumulation of ruptured lysosomes, impaired autophagic flux, and superfluous reactive oxygen species, consequently leading to cell death and tumor suppression. CCDC50 expression is associated with malignancy, progression to metastasis, and poor overall survival in human melanoma. Targeting CCDC50 suppresses tumor growth and lung metastasis, and enhances the effect of BRAFV600E inhibition. Thus, we demonstrate critical roles of CCDC50-mediated clearance of damaged lysosomes in supporting tumor growth, hereby identifying a potential therapeutic target of melanoma.

Pulsed field ablation for pulmonary vein isolation: Preclinical safety and effectiveness of a novel hexaspline ablation catheter.

BACKGROUND: Pulsed-field ablation (PFA) has emerged as a nonthermal energy source for cardiac ablation, with potential safety advantages over radiofrequency ablation (RFA) and cryoballoon ablation. OBJECTIVE: To report the preclinical results of a novel hexaspline PFA catheter for pulmonary vein isolation (PVI), and to verify the influence of PFA on esophagus by comparing with RFA. METHODS: This study included a total of 15 canines for the efficacy and safety study and four swine for the esophageal safety study. The 15 canines were divided into an acute cohort (n = 3), a 30-day follow-up cohort (n = 5) and a 90-day follow-up cohort (n = 7), PVI was performed with the novel hexaspline PFA ablation catheter. In the esophageal safety study, four swine were divided into PFA cohort (n = 2) and RFA cohort (n = 2), esophageal injury swine model was adopted, the esophagus was intubated with an esophageal balloon retractor, under fluoroscopy, the DV8 device was inflated with a mixture of saline and contrast and rotated to displace the esophagus rightward and anteriorly toward the ablation catheter in the inferior vena cava (IVC) and right inferior pulmonary vein (PV). Nine PFA applications were delivered at four locations on IVC and two locations on the right inferior PV in the PFA cohort, six RFA applications were delivered at each location in the RFA group. Histopathological analysis of all PVs, esophagus, IVC, and the adjacent lungs was performed. RESULTS: Acute PV isolation was achieved in all 15 canines (100%), with energy delivery times of less than 3 min/animal. In the 30 and 90 days group, the overall success rates were 88.9% and 88.5% per PVs, respectively. Two right superior pulmonary veins (RSPVs) in the 30-day group, two RSPVs and one left superior PV in the 90-day group with recovered potentials. At follow-up, gross pathological examination revealed the lesions around the PVs were continuous and transmural. Masson's trichrome staining revealed the myocardial cells in the PVs became fibrotic, but small arteries and nervous tissue were preserved. Results of swine esophageal injury model revealed the esophageal luminal surface was smooth and without evidence for esophageal injury in the PFA group, whereas obvious ulceration was detected on the esophagus tunica mucosa in the RFA group. CONCLUSION: In the chronic canine study, PFA-based PVI were safe and effective with demonstrable sparing of nerves and venous tissue. Compared with RFA, there was also good evidence for safety of PFA, avoiding PV stenosis and esophageal injury. This preclinical study provided the scientific basis for the first-in-human endocardial PFA studies.

Venous anatomy of the left ventricular summit region: Insights from high-speed rotational retrograde angiography.

INTRODUCTION: Mapping and ablation through the coronary venous system (CVS) have shown potential for ventricular arrhythmias originating from the left ventricular summit (LVS). Multielectrode catheters and balloons are frequently used for mapping and venous ethanol ablation (VEA). However, there is limited data on the venous size and drainage condition in the LVS region. This study aimed to investigate the morphology, angiographic size, and drainage condition of LV summit veins via high-speed rotational angiography (RA). METHODS: We measured and analyzed the size of the great cardiac vein (GCV), the anterior interventricular vein (AIV), veins near to the LVS, and other main tributaries of CVS in 102 patients undergoing electrophysiology study. RESULTS: Rotational retrograde angiography of LVS was successfully performed in 81 patients. The diameter of GCV at the level of the Vieussens valve and the distal end of GCV (junction of GCV-AIV) was larger in males than females (6.8 ± 1.1 vs. 5.6 ± 1.2 mm, p < .001; 5.2 ± 0.9 vs. 4.6 ± 0.8, p = .002, respectively) while no significant gender differences were observed in other tributaries. The LV summit veins presented downward drainage direction in half of the patients, indicating potential anatomic adjacency with His bundle. Left anterior oblique (LAO) 45° projection might provide the practical and optimal view of the LV summit veins. CONCLUSIONS: The coronary veins of the LVS region present various anatomical morphologies and ostium sizes. We provide a systematic description and angiographic size spectrum of CVS. RA could facilitate assessing the feature of CVS comprehensively.

Electrophysiological responses of the left atrial appendage during pulsed-field electrical isolation utilizing a novel device in a canine model.

BACKGROUND: The electrophysiological responses of the left atrial appendage (LAA) during pulsed-field electrical isolation have not been established. OBJECTIVE: This study aims to investigate the electrical responses of the LAA during pulsed-field electrical isolation using a novel device and their relations to acute isolation success. METHODS: Six canines were enrolled. The E-SeaLA™ device, which is able to perform LAA occlusion and ablation simultaneously, was deployed into the LAA ostium. LAA potentials (LAAp) were mapped via a mapping catheter, and the LAAp recovery time (LAAp RT, the time between the last pulsed spike and the first recovered LAAp) was measured after pulsed-train delivery. The initial pulse index (PI, corelated to pulsed-field intensity) was adjusted during the ablation procedure until LAAEI was achieved. Acute LAA electrical isolation (LAAEI) success was defined as LAAp disappearance or exit and entrance conduction block, confirmed through a drug test and a 60-minute waiting period. RESULT: All canines achieved successful LAA occlusion without peri-device leaks. Acute LAA electrical isolation (LAAEI) was achieved in five out of six canines (5/6, 83.3%). Very late LAAp recurrence (LAAp RT > 600 s) was observed during PFA. Early recurrence (LAAp RT < 30 s) was observed in two canines (2/6, 33.3%) post-PFA. Intermediate recurrence (LAAp RT ~ 120 s) was observed in three canines (3/6, 50%) post-PFA. The two canines with intermediate recurrence achieved LAAEI with higher PI ablations. The one canine with early LAAp recurrence had a peri-device leak and achieved LAAEI by the same PI after replacing with a larger size device and eliminating the peri-device leak. Another canine with early recurrence (1/6, 16.7%) failed to achieve LAAEI due to epicardial connection with persistent left superior vena cava. No coronary spasm, stenosis or other complications were observed. CONCLUSION: These results suggest that with proper device-tissue contact and pulse intensity, LAAEI can be achieved using this novel device without serious complications. The LAAp RT patterns observed in this study could inform and guide the adjustment of the ablation strategy.

Rapamycin antagonizes angiogenesis and lymphangiogenesis through myeloid-derived suppressor cells in corneal transplantation.

Rapamycin is an immunosuppressive drug that is widely used in the postsurgery management of transplantation. To date, the mechanism by which rapamycin reduces posttransplant neovascularization has not been fully understood. Given the original avascularity and immune privilege of the cornea, corneal transplantation is considered as an ideal model to investigate neovascularization and its effects on allograft rejection. Previously, we found that myeloid-derived suppressor cells (MDSC) prolong corneal allograft survival through suppression of angiogenesis and lymphangiogenesis. Here, we show that depletion of MDSC abolished rapamycin-mediated suppression of neovascularization and elongation of corneal allograft survival. RNA-sequencing analysis revealed that rapamycin dramatically enhanced the expression of arginase 1 (Arg1). Furthermore, an Arg1 inhibitor also completely abolished the rapamycin-mediated beneficial effects after corneal transplantation. Taken together, these findings indicate that MDSC and elevated Arg1 activity are essential for the immunosuppressive and antiangiogenic functions of rapamycin.

Microstructure and Mechanical Properties of W-Al2O3 Alloy Plates Prepared by a Wet Chemical Method and Rolling Process.

The uneven distribution and large size of the second phase weakens the effect of dispersion strengthening in ODS-W alloys. In this article, the W-Al2O3 composite powders were fabricated using a wet chemical method, resulting in a finer powder and uniformly dispersed Al2O3 particles in the tungsten-based alloy. The particle size of the pure tungsten powder is 1.05 µm and the particle size of W-0.2 wt.%Al2O3 is 727 nm. Subsequently, the W-Al2O3 alloy plates were successfully obtained by induction sintering and rolling processes. Al2O3 effectively refined grain size from powder-making to sintering. The micro-hardness of the tungsten alloy plates reached 512 HV0.2, which is 43.7% higher than that of pure tungsten plates. The nano-hardness reached 14.2 GPa, which is 24.1% higher than that of the pure tungsten plate; the compressive strength reached 2224 MPa, which is 37.2% higher than that of the pure tungsten.

Novel Bcl-2 Inhibitors Selectively Disrupt the Autophagy-Specific Bcl-2-Beclin 1 Protein-Protein Interaction.

Autophagy plays essential roles in a wide variety of physiological processes, such as cellular homeostasis, metabolism, development, differentiation, and immunity. Selective pharmacological modulation of autophagy is considered a valuable potential therapeutic approach to treat diverse human diseases. However, development of such therapies has been greatly impeded by the lack of specific small molecule autophagy modulators. Here, we performed structure-activity relationship studies on a previously discovered weak Bcl-2 inhibitor SW076956, and developed a panel of small molecule compounds that selectively released Bcl-2-mediated inhibition of autophagy-related Beclin 1 compared to apoptosis-related Bax at nanomolar concentration. Our NMR analysis showed that compound 35 directly binds Bcl-2 and specifically inhibits the interaction between the Bcl-2 and Beclin 1 BH3 domains without disruption of the Bcl-2-Bax BH3 interaction. More broadly, this proof-of-concept study demonstrates that targeting protein-protein interactions of the intrinsic autophagy regulatory network can serve as a valuable strategy for the development of autophagy-based therapeutics.

Tonoplast-localized transporter ZmNRAMP2 confers root-to-shoot translocation of manganese in maize.

Almost all living organisms require manganese (Mn) as an essential trace element for survival. To maintain an irreplaceable role in the oxygen-evolving complex of photosynthesis, plants require efficient Mn uptake in roots and delivery to above-ground tissues. However, the underlying mechanisms of root-to-shoot Mn translocation remain unclear. Here, we identified an Natural Resistance Associated Macrophage Protein (NRAMP) family member in maize (Zea mays), ZmNRAMP2, which localized to the tonoplast in maize protoplasts and mediated transport of Mn in yeast (Saccharomyces cerevisiae). Under Mn deficiency, two maize mutants defective in ZmNRAMP2 exhibited remarkable reduction of root-to-shoot Mn translocation along with lower shoot Mn contents, resulting in substantial decreases in Fv/Fm and plant growth inhibition compared to their corresponding wild-type (WT) plants. ZmNRAMP2 transcripts were highly expressed in xylem parenchyma cells of the root stele. Compared to the WT, the zmnramp2-1 mutant displayed lower Mn concentration in xylem sap accompanied with retention of Mn in root stele. Furthermore, the overexpression of ZmNRAMP2 in transgenic maize showed enhanced root-to-shoot translocation of Mn and improved tolerance to Mn deficiency. Taken together, our study reveals a crucial role of ZmNRAMP2 in root-to-shoot translocation of Mn via accelerating vacuolar Mn release in xylem parenchyma cells for adaption of maize plants to low Mn stress and provides a promising transgenic approach to develop low Mn-tolerant crop cultivars.

Expression analysis and functional characterization of tomato Tubby-like protein family.

Tubby-like protein (TLP) plays an important role in plant growth and development. In this investigation, the characteristics of 11 members in the SlTLP family were studied. SlTLP genes were classified into two subgroups, and the members containing the F-box domain were renamed SlTLFPs. Subcellular localization indicated that most of the SlTLPs were localized in the nucleus. Expression pattern analysis revealed that eight genes (SlTLFP1, 3, 5, 7-10, and SlTLP11) showed differential expression across various tissues, while SlTLFP2, 4, and 6 were widely expressed in all the organs tested. Most SlTLP genes were induced by biotic and abiotic stress treatments such as Botrytis cinerea, temperature, MeJA, and ABA. TLP proteins in tomato have no transcriptional activation activity, and most members with an F-box domain could interact with SUPPRESSOR OF KINETOCHORE PROTEIN 1 (SlSkp1) or Cullin1 (Cul1) or both. Experiments on CRISPR edited SlTLFP8 showed that the N-terminal F-box domain was necessary for its function such as DNA ploidy and stomata size regulation. Our findings suggested that the F-box domain interacts with Skp1 and Cul1 to form the SCF complex, suggesting that SlTLFPs, at least SlTLFP8, function mainly through the F-box domain as an E3 ligase.

OsAMT1;1 and OsAMT1;2 Coordinate Root Morphological and Physiological Responses to Ammonium for Efficient Nitrogen Foraging in Rice.

Optimal plant growth and development rely on morphological and physiological adaptions of the root system to forage heterogeneously distributed nitrogen (N) in soils. Rice grows mainly in the paddy soil where ammonium (NH4+) is present as the major N source. Although root NH4+ foraging behaviors are expected to be agronomically relevant, the underlying mechanism remains largely unknown. Here, we showed that NH4+ supply transiently enhanced the high-affinity NH4+ uptake and stimulated lateral root (LR) branching and elongation. These synergistic physiological and morphological responses were closely related to NH4+-induced expression of NH4+ transporters OsAMT1;1 and OsAMT1;2 in roots. The two independent double mutants (dko) defective in OsAMT1;1 and OsAMT1;2 failed to induce NH4+ uptake and stimulate LR formation, suggesting that OsAMT1s conferred the substrate-dependent root NH4+ foraging. In dko plants, NH4+ was unable to activate the expression of OsPIN2, and the OsPIN2 mutant (lra1) exhibited a strong reduction in NH4+-triggered LR branching, suggesting that the auxin pathway was likely involved in OsAMT1s-dependent LR branching. Importantly, OsAMT1s-dependent root NH4+ foraging behaviors facilitated rice growth and N acquisition under fluctuating NH4+ supply. These results revealed an essential role of OsAMT1s in synergizing root morphological and physiological processes, allowing for efficient root NH4+ foraging to optimize N capture under fluctuating N availabilities.

Heat shock-induced cold acclimation in cucumber through CsHSFA1d-activated JA biosynthesis and signaling.

Cucumber (Cucumis sativus) originated in tropical areas and is very sensitive to low temperatures. Cold acclimation is a universal strategy that improves plant resistance to cold stress. In this study, we report that heat shock induces cold acclimation in cucumber seedlings, via a process involving the heat-shock transcription factor HSFA1d. CsHSFA1d expression was improved by both heat shock and cold treatment. Moreover, CsHSFA1d transcripts accumulated more under cold treatment after a heat-shock pre-treatment than with either heat shock or cold treatment alone. After exposure to cold, cucumber lines overexpressing CsHSFA1d displayed stronger tolerance for cold stress than the wild type, whereas CsHSFA1d knockdown lines obtained by RNA interference were more sensitive to cold stress. Furthermore, both the overexpression of CsHSFA1d and heat-shock pre-treatment increased the endogenous jasmonic acid (JA) content in cucumber seedlings after cold treatment. Exogenous application of JA rescued the cold-sensitive phenotype of CsHSFA1d knockdown lines, underscoring that JA biosynthesis is key for CsHSFA1d-mediated cold tolerance. Higher JA content is likely to lead to the degradation of CsJAZ5, a repressor protein of the JA pathway. We also established that CsJAZ5 interacts with CsICE1. JA-induced degradation of CsJAZ5 would be expected to release CsICE1, which would then activate the ICE-CBF-COR pathway. After cold treatment, the relative expression levels of ICE-CBF-COR signaling pathway genes, such as CsICE1, CsCBF1, CsCBF2 and CsCOR1, in CsHSFA1d overexpression lines were significantly higher than in the wild type and knockdown lines. Taken together, our results help to reveal the mechanism underlying heat shock-induced cold acclimation in cucumber.

Cadmium-Doped Zinc Sulfide Shell as a Hole Injection Springboard for Red, Green, and Blue Quantum Dot Light-Emitting Diodes.

A new strategy is developed in which cadmium-doped zinc sulfide (CdZnS) is used as the outermost shell to synthesize red, green, and blue (RGB) quantum dots (QDs) with the core/shell structures of CdZnSe/ZnSe/ZnS/CdZnS, CdZnSe/ZnSe/ZnSeS/CdZnS, and CdZnSe/ZnSeS/ZnS/CdZnS, respectively. Firstly, the inner ZnS and ZnSe shells confine the excitons inside the cores of QDs and provide a better lattice matching with respect to the outermost shell, which ensures high photoluminescence quantum yields of QDs. Secondly, the CdZnS shell affords its QDs with shallow valence bands (VBs). Therefore, the CdZnS shell could be used as a springboard, which decreases the energy barrier for hole injection from polymers to QDs to be below 1.0 eV. It makes the holes to be easily injected into the QD EMLs and enables a balanced recombination of charge carriers in quantum dot light-emitting diodes (QLEDs). Thirdly, the RGB QLEDs made by these new QDs exhibit peak external quantum efficiencies (EQEs) of 20.2%, 19.2%, and 8.4%, respectively. In addition, the QLEDs exhibit unexpected luminance values at low applied voltages and therefore high power efficiencies. From these results, it is evident that CdZnS could act as an excellent shell and hole injection springboard to afford high performance QLEDs.

MicroRNA Profiling During Mulberry (Morus atropurpurea Roxb) Fruit Development and Regulatory Pathway of miR477 for Anthocyanin Accumulation.

To understand the mechanism of small non-coding RNAs (miRNA)-mediated development and ripening of mulberry fruits, three small RNA libraries from mulberry fruits at different development stages were constructed, and 159 conserved miRNAs as well as 86 novel miRNAs were successfully identified. Among the miRNAs identified, there were 90 miRNAs which showed differential expression patterns at different stages of fruit development and ripening. The target genes of these differential expressed (DE) miRNAs were involved in growth and development, transcription and regulation of transcription, metabolic processes, and etc. Interestingly, it was found that the expression level of mul-miR477 was increased with fruit ripening, and it can target the antisense lncRNA (Mul-ABCB19AS) of the ATP binding cassette (ABC) transporter B 19 gene (Mul-ABCB19). Our results showed that mul-miR477 can repress the expression of Mul-ABCB19AS and increase the expression of Mul-ABCB19, and it acted as a positive regulator participating anthocyanin accumulation through the regulatory network of mul-miR477-Mul-ABCB19AS-Mul-ABCB19.

Transcriptome and DNA Methylome Reveal Insights Into Phytoplasma Infection Responses in Mulberry (Morus multicaulis Perr.).

To reveal whether the response of mulberry to phytoplasma infection is associated with genome-wide DNA methylation changes, the methylome and transcriptome patterns of mulberry in response to phytoplasma infection were explored. Though the average methylation level of the infected leaves showed no significant difference from that of healthy leaves, there were 1,253 differentially methylated genes (DMGs) and 1,168 differentially expressed genes (DEGs) in the infected leaves, and 51 genes were found simultaneously to be differently methylated and expressed. It was found that the expression of G-type lectin S-receptor-like serine/threonine protein kinase gene (Mu-GsSRK) was increased, but its methylation level was decreased in the pathogen-infected or salicylic acid (SA)-treated leaves. Overexpression of Mu-GsSRK in Arabidopsis and in the hairy roots of mulberry enhanced transgenic plant resistance to the phytoplasma. Moreover, overexpression of Mu-GsSRK enhanced the expressions of pathogenesis-related protein 1, plant defensin, and cytochrome P450 protein CYP82C2 genes in transgenic plants inoculated with pathogens, which may contribute to the enhanced disease resistance against various pathogens. Finally, the DNA methylation dynamic patterns and functions of the differentially expressed and methylated genes were discussed. The results suggested that DNA methylation has important roles in mulberry responses to phytoplasma infection.

Research Advances in Heterotrimeric G-Protein α Subunits and Uncanonical G-Protein Coupled Receptors in Plants.

As crucial signal transducers, G-proteins and G-protein-coupled receptors (GPCRs) have attracted increasing attention in the field of signal transduction. Research on G-proteins and GPCRs has mainly focused on animals, while research on plants is relatively rare. The mode of action of G-proteins is quite different from that in animals. The G-protein α (Gα) subunit is the most essential member of the G-protein signal cycle in animals and plants. The G-protein is activated when Gα releases GDP and binds to GTP, and the relationships with the GPCR and the downstream signal are also achieved by Gα coupling. It is important to study the role of Gα in the signaling pathway to explore the regulatory mechanism of G-proteins. The existence of a self-activated Gα in plants makes it unnecessary for the canonical GPCR to activate the G-protein by exchanging GDP with GTP. However, putative GPCRs have been found and proven to play important roles in G-protein signal transduction. The unique mode of action of G-proteins and the function of putative GPCRs in plants suggest that the same definition used in animal research cannot be used to study uncanonical GPCRs in plants. This review focuses on the different functions of the Gα and the mode of action between plants and animals as well as the functions of the uncanonical GPCR. This review employs a new perspective to define uncanonical GPCRs in plants and emphasizes the role of uncanonical GPCRs and Gα subunits in plant stress resistance and agricultural production.

Sorting nexin 5 mediates virus-induced autophagy and immunity.

Autophagy, a process of degradation that occurs via the lysosomal pathway, has an essential role in multiple aspects of immunity, including immune system development, regulation of innate and adaptive immune and inflammatory responses, selective degradation of intracellular microorganisms, and host protection against infectious diseases1,2. Autophagy is known to be induced by stimuli such as nutrient deprivation and suppression of mTOR, but little is known about how autophagosomal biogenesis is initiated in mammalian cells in response to viral infection. Here, using genome-wide short interfering RNA screens, we find that the endosomal protein sorting nexin 5 (SNX5)3,4 is essential for virus-induced, but not for basal, stress- or endosome-induced, autophagy. We show that SNX5 deletion increases cellular susceptibility to viral infection in vitro, and that Snx5 knockout in mice enhances lethality after infection with several human viruses. Mechanistically, SNX5 interacts with beclin 1 and ATG14-containing class III phosphatidylinositol-3-kinase (PI3KC3) complex 1 (PI3KC3-C1), increases the lipid kinase activity of purified PI3KC3-C1, and is required for endosomal generation of phosphatidylinositol-3-phosphate (PtdIns(3)P) and recruitment of the PtdIns(3)P-binding protein WIPI2 to virion-containing endosomes. These findings identify a context- and organelle-specific mechanism-SNX5-dependent PI3KC3-C1 activation at endosomes-for initiation of autophagy during viral infection.

Myeloid-derived suppressor cells improve corneal graft survival through suppressing angiogenesis and lymphangiogenesis.

Myeloid-derived suppressor cells (MDSC) are one of the major negative regulators of immune responses during many pathological conditions such as cancer and transplantation. Emerging evidence indicates that MDSC also contribute to tumor progression through their pro-angiogenic activity in addition to immunosuppressive function. However, virtually nothing is known about the role of MDSC in the regulation of neovascularization after transplantation. Here we showed that antibody-mediated depletion of MDSC in mice led to robust growth of blood and lymphatic neovessels and rapid allograft rejection after corneal penetrating keratoplasty. In contrast, adoptive transfer of ex vivo generated MDSC from cytokine-treated bone marrow cells (evMDSC) suppressed neovascularization and prolonged corneal allograft survival in an inducible nitric oxide synthase (iNOS)-dependent manner. Mechanistically, compared to naïve MDSC control, evMDSC have increased expression of an anti-angiogenic factor thrombospondin 1 (Tsp-1) and decreased expression of two critical pro-angiogenic factors, vascular endothelial growth factor A (VEGF-A), and VEGF-C. These findings demonstrate MDSC as a critical anti-angiogenic regulator during transplantation. Our study also indicates that evMDSC are a valuable candidate agent for development of novel cell therapy to improve allograft survival after transplantation.