Loss of primary cilia is common in cancer, but its relevance to molecular subtypes of muscle-invasive bladder cancer (MIBC) is unclear. Here, we combined transcriptomic and co-expression analyses with experiments in bladder cancer cell lines, human tumor specimens, and xenografts to investigate the basis of cilia loss in basal MIBC. Primary cilia were less frequent in basal than in luminal MIBC. Depletion of IFT88 reduced ciliogenesis and increased cell proliferation and migration. Conversely, IFT88 overexpression restored cilia, delayed the appearance of palpable xenografts, and limited xenograft growth. NEK2 was enriched in basal MIBC, and higher expression in TCGA was associated with shorter disease-free survival. In basal bladder cancer cells, NEK2 knockdown increased IFT88 abundance and cilia formation and reduced proliferation and migration; NEK2 overexpression had the opposite effects. Rescue experiments showed that these effects of NEK2 depended on IFT88. NEK2 interacted with IFT88, increased its ubiquitination, and accelerated its proteasomal turnover. AURKA knockdown reduced IFT88 ubiquitination after NEK2 overexpression and attenuated the associated cilia loss, proliferation, and migration, whereas AURKA overexpression reversed the effects of NEK2 knockdown. In a xenograft experiment, pretreating IFT88-overexpressing cells with the NEK2 inhibitor JH295 produced the greatest reduction in tumor establishment and growth among the four conditions tested. These data identify a NEK2-AURKA-IFT88 pathway that promotes ubiquitin-dependent IFT88 degradation and cilia loss in basal MIBC models, providing a preclinical basis for further testing of NEK2 targeting in cilia-deficient basal MIBC.

Delayed diabetic wound healing is a global health issue with unclear pathogenesis. Ferroptosis, a form of cell death involving iron and lipid peroxidation, may contribute to delayed diabetic wound. This study investigates the role of ferroptosis in diabetic wound keratinocytes. We measured lipid peroxidation products (MDA, 4-HNE), ACSL4, and GPX4 protein levels in diabetic keratinocytes and assessed mitochondrial morphology. Ferrostatin-1 (Fer-1) was used to inhibit ferroptosis in diabetic rat wounds, and its effects on healing and expression levels were evaluated. Pull-down assays, silver staining, and mass spectrometry were employed to study ACSL4 mRNA regulation. A YTHDF2 knockdown adenovirus was used to manipulate YTHDF2 expression in rat wounds. Ferroptosis was detected in diabetic keratinocytes, hindering wound healing, a process reversible with Fer-1. High glucose induced ACSL4 expression, driving keratinocyte ferroptosis and delayed healing. YTHDF2 interacts with N6-Methyladenosine-modified ACSL4 mRNA, affecting its stability and expression. YTHDF2 knockdown increased ACSL4, promoting ferroptosis and impairing healing. Our findings illustrate the significant involvement of ferroptosis in the dysfunction of diabetic keratinocytes, suggesting that targeting ferroptosis may offer a viable therapeutic approach for improving diabetic wound healing.

Introduction and Objective: Metabolic dysfunction-associated fatty liver disease (MAFLD) is a prevalent chronic liver disease linked to obesity and metabolic disorders. Caloric restriction (CR) and intermittent fasting (IF) improve metabolic health, but their effects on MAFLD and underlying mechanisms are unclear. This study compared CR and IF regimens in MAFLD models and explored the role of glutathione S-transferase Mu3 (GSTM3) in mediating these effects. Methods: MAFLD was induced in db/db and HFD/STZ-treated C57 mice. Animals underwent ad libitum feeding, CR, or EODF for 56 days. Metabolic parameters, liver pathology, and mitochondrial function were assessed. Transcriptomics identified GSTM3 as a key target, validated by RT-qPCR, Western blot, and immunofluorescence. CREB1 regulation of GSTM3 was confirmed by ChIP assays. Liver-specific GSTM3 overexpression was evaluated in mouse models. Results: Under matched caloric restriction conditions, both CR and EODF similarly improved body weight, liver lipid deposition, inflammatory levels, and glucose metabolism in MAFLD mice. Both CR and EODF significantly upregulated the expression of GSTM3 in the liver, mediated by the transcription factor CREB1. GSTM3 expression was reduced in MAFLD patients and animal models, while overexpression of GSTM3 significantly alleviated liver lipid accumulation, inflammation, and insulin resistance, improved mitochondrial function, and promoted fatty acid oxidation. Mechanistically, GSTM3 localized to the mitochondria, scavenged reactive oxygen species and lipid peroxides, and protected mitochondrial function. Conclusion: The intensity, rather than the type, of caloric restriction plays a key role in ameliorating MAFLD. CR upregulates GSTM3 expression in a CREB1-dependent manner, enhances mitochondrial function, and promotes fatty acid oxidation, thereby effectively improving the pathological state of MAFLD. GSTM3 may serve as a potential therapeutic target for MAFLD X. Hong: None. S. Chen: None. J. Lin: None. M. Ren: None. L. Yan: None. W. Wang: None. National Natural Science Foundationof China (U20A20352), Guangdong Basic and Applied Basic Research Foundation (2023A1515030079)

Gliomas, the most prevalent and lethal form of brain cancer, are known to exhibit metabolic alterations that facilitate tumor growth, invasion, and resistance to therapies. Peroxisomes, essential organelles responsible for fatty acid oxidation and reactive oxygen species (ROS) homeostasis, rely on the receptor PEX5 for the import of metabolic enzymes into their matrix. However, the prognostic significance of peroxisomal enzymes for glioma patients remains unclear. In this study, we elucidate that PEX5 is indispensable for the cell growth, migration, and invasion of glioma cells. We establish a robust prognosis model based on the expression of peroxisomal enzymes, whose localization relies on PEX5. This PEX5-dependent signature not only serves as a robust prognosis model capable of accurately predicting outcomes for glioma patients, but also effectively distinguishes several clinicopathological features, including the grade, isocitrate dehydrogenase (IDH) mutation, and 1p19q codeletion status. Furthermore, we developed a nomogram that integrates the prognostic model with other clinicopathological factors, demonstrating highly accurate performance in estimating patient survival. Patients classified into the high-risk group based on our prognostic model exhibited an immunosuppressive microenvironment. Finally, our validation reveals that the elevated expression of GSTK1, an antioxidant enzyme within the signature, promotes the cell growth and migration of glioma cells, with this effect dependent on the peroxisomal targeting signal recognized by PEX5. These findings identify the PEX5-dependent signature as a promising prognostic tool for gliomas.

Mycobacterium tuberculosis, the pathogen of the deadly disease tuberculosis, depends on the redox cofactor mycofactocin (MFT) to adapt to and survive under hypoxic conditions. MftR is a TetR family transcription regulator that binds upstream of the MFT gene cluster and controls MFT synthesis. To elucidate the structural basis underlying MftR regulation, we determined the crystal structure of Mycobacterium tuberculosis MftR (TB-MftR). The structure revealed an interconnected hydrogen bond network in the α1-α2-α3 helices of helix-turn-helix (HTH) DNA-binding domain that is essential for nucleic acid interactions. The ligand-binding domain contains a hydrophobic cavity enclosing long-chain fatty acyl-CoAs like the key regulatory ligand oleoyl-CoA. Despite variations in ligand-binding modes, comparative analyses suggest regulatory mechanisms are largely conserved across TetR family acyl-CoA sensors. By elucidating the intricate structural mechanisms governing DNA and ligand binding by TB-MftR, our study enhances understanding of the regulatory roles of this transcription factor under hypoxic conditions, providing insights that could inform future research into Mycobacterium tuberculosis pathogenesis.

Mucosal-associated invariant T (MAIT) cells exert multifaceted effects such as anti-microbial activity, tissue repair, and pro-fibrotic effects across various disease settings. Nonetheless, their role in liver injury and hemostasis is a current topic of debate. Here, we presented a MAIT cell-centered profiling in chronic HBV-infected patients with varying degree of liver injury and those who underwent liver transplantation. Liver transplantation facilitated a gradual recovery of recipient-originated MAIT cells from dysregulation associated with disease severity and accumulated bile acids in liver failure. Transcriptome analysis and T cell receptor (TCR) mining indicated an upregulation in MAIT cell migration during liver injury and post liver transplantation, characterized by elevated liver egress in the former and rescued liver homing receptors in the latter. TCR activation exacerbated the pathological potency of MAIT cells from liver failure patients, but conferred a protective potential in those from transplant recipients. Compromised recovery of MAIT cells was linked to post-transplantation complications, whereas prompt recovery predicated a more favorable clinical outcome. These findings underscore the intricate interplay between MAIT cells and the hepatic environment, highlighting MAIT cells as potential therapeutic targets and sensitive predictors for clinical outcome in individuals experiencing liver failure and post liver transplantation.

BACKGROUND Glioblastomas are universally lethal brain tumors containing tumor-propagating glioblastoma stem cells (GSCs). EGFR gene amplification or mutation is frequently detected in GBMs and is associated with poor prognosis. However, EGFR variants in GSCs and their role in the maintenance of GSCs and progression of GBM are unclear. METHODS EGFR variants were detected through bioinformatic HISAT-StringTie-Ballgown pipeline and verified through 5' RACE, RT-PCR, ribonuclease protection, and northern blotting assays. EGFRx function was investigated through neurosphere, cell viability, intracranial xenograft and RNA-seq assays. EGFRx-STAT5 signaling was investigated through western blotting, coimmunoprecipitation, immunofluorescence, luciferase reporter, RT-PCR and CUT&Tag assays. RESULTS We identified a novel EGFR variant (EGFRx), that is specifically expressed in GSCs. Unlike the EGFRvIII variant, which lacks exons 2-7, EGFRx is characterized by the absence of exons 2-14, and encodes an EGFR protein that does not possess the entire extracellular ligand-binding domain. We observed that EGFRx exhibits significant glycosylation, is required for GSC self-renewal, proliferation, and tumorigenesis, and highly active in glioblastomas compared to normal brain tissue. Mechanistically, EGFRx constitutively and specifically activates STAT5 in GSCs through spontaneous asymmetric dimerization of the kinase domain. CONCLUSIONS EGFRx plays essential roles in the maintenance of the GSC phenotype through constitutive activation of STAT5 and promotes GBM progression, suggesting that EGFRx-STAT5 signaling represents a promising therapeutic target for GBM.

AbstractIntron retention (IR) constitutes a less explored form of alternative splicing, wherein introns are retained within mature mRNA transcripts. This investigation demonstrates that the cell division cycle (CDC)‐like kinase 2 (CLK2) undergoes liquid–liquid phase separation (LLPS) within nuclear speckles in response to heat shock (HS). The formation of CLK2 condensates depends on the intrinsically disordered region (IDR) located within the N‐terminal amino acids 1‐148. Phosphorylation at residue T343 sustains CLK2 kinase activity and promotes overall autophosphorylation, which inhibits the LLPS activity of the IDR. These CLK2 condensates initiate the reorganization of nuclear speckles, transforming them into larger, rounded structures. Moreover, these condensates facilitate the recruitment of splicing factors into these compartments, restricting their access to mRNA for intron splicing and promoting the IR. The retained introns lead to the sequestration of transcripts within the nucleus. These findings extend to the realm of glioma stem cells (GSCs), where a physiological state mirroring HS stress inhibits T343 autophosphorylation, thereby inducing the formation of CLK2 condensates and subsequent IR. Notably, expressing the CLK2 condensates hampers the maintenance of GSCs. In conclusion, this research unveils a mechanism by which IR is propelled by CLK2 condensates, shedding light on its role in coping with cellular stress.

Background and aimsT cells are master effectors of anti-tumor immunity in cancer. Recent studies suggest that altered lipid metabolism imposed by the tumor microenvironment constrains anti-tumor immunity. However, the tumor-associated lipid species changes that dampen T cell ability to control tumor progression are not fully understood. Here, we plan to clarify the influences of distinctly altered lipid components in hepatitis B virus (HBV)-related hepatocellular carcinoma (HCC) on T-cell function, aiming to seek lipid metabolic targets for improving T cell anti-tumor effects. MethodsTumor tissues and non-tumor liver from HCC patients were collected for RNA-sequencing, lipid profiling and T cell characterizing, followed by correlation analysis. Additionally, the effects of significantly changed lipid components on anti-tumor potential of T cells were tested by in vitro cell experiments and/or in vivo tumor inoculated model. ResultsAltered lipid metabolism coincides with impaired T cell response in HBV-related HCC. Characteristic lipid composition, significantly marked by accumulation of long-chain acylcarnitines (LCACs) and reduction of lysophosphatidylcholines (LPCs), are found in the tumor tissue. Notably, LCACs accumulated are associated with T cells exhaustion and deficient functionality, while LPCs correlate to anti-tumor effects of T cells. In particular, supplement of LPCs, including LPC (20:0) and LPC (22:0), directly promote the activation and IFN-gamma secretion of T cells in vitro, and suppress tumor growth in vivo. ConclusionsOur study highlights the distinctly changed lipid components closely related to T cell dysregulation in HCC, and suggests a promising strategy by decreasing LCACs and increasing LPCs for anti-tumor immunotherapy.

Eicosapentaenoic acid (EPA) has been reported to play an anti-inflammatory and antioxidative stress role in a series of human diseases, including major depressive disorder. However, its exact mechanism is still largely unknown. Mouse BV-2 cells were treated with lipopolysaccharide (LPS) to induce an in vitro inflammatory cell model of depression. Cytotoxic effects were assessed with MTT and lactate dehydrigebase release assays. Cytokine mediators were elevated by western blot and enzyme-linked immunosorbent assays. Autophagy-relators were determined by immunofluorescence and western blot analyses. Interaction relationships among molecules were evaluated utilizing chromatin immunoprecipitation and dual luciferase assays. Methylated miR-29a-3p was detected via methylation-specific polymerase chain reaction. EPA treatment at 60 μM had no cytotoxic effects on BV2 cells and significantly inhibited the LPS-induced inflammatory response and NLRP3 inflammasome but activated autophagy, while all these effects were reversed by the autophagy inhibitor 3-MA. Importantly, miR-29a-3p exhibited a role similar to that of EPA in LPS-treated BV2 cells. Mechanistically, EPA treatment elevated miR-29a-3p by repressing its promoter methylation. MAPK8 was a direct target of miR-29a-3p. Inhibition of miR-29a-3p greatly diminished the regulatory roles mediated by EPA in LPS-treated BV2 cells, while these roles were further impeded after MAPK8 silencing. To conclude, our data demonstrated that EPA treatment alleviated LPS-induced NLRP3 inflammasomes by activating autophagy via regulation of miR-29a-3p/MAPK8 signaling, which further elucidates the potential antidepressant mechanism of EPA.

• Our results disclosed a dihelical structure of Enterovirus A71 3A 1–57 protein in apo form. • We depicted rigid helices and a unique flexible C-terminus for apo-form 3A 1–57 . • This study revealed a competitive binding-based molecular mechanism underlying inhibition of dimeric 3A by ER-DRI.

Saro_0803 is a transcriptional factor modulating the transcription of the stilbene-degrading enzyme gene nov1 in Novosphingobium aromaticivorans DSM 12444. Reportedly, Saro_0803 undergoes resveratrol-mediated dissociation from the nov1 promotor and distinguishes resveratrol from its precursors, p-coumaric acid and trans-cinnamic acid, enabling the transcriptional factor to serve as a biosensor component for regulating resveratrol biosynthesis. However, little is known about the molecular mechanisms underlying the Saro_0803 interactions with either the nov1 promotor gene or resveratrol, which undermines the potential for Saro_0803 to be further modified for improved biosynthetic performance and other applications. Here, we report the discovery of the 22 bp A/T-rich Saro_0803 binding site near the −10 box of the nov1 promotor (named nov1p22bp). As validated by molecular docking-guided mutagenesis and binding affinity assays, the Saro_0803 binding of its target DNA sequence relies on charge-predominating interactions between several typical positively charged residues and nucleic acid. Furthermore, we semi-quantified the influence of resveratrol presence on Saro_0803–nov1p22bp interaction and identified a bilateral hydrophobic pocket within Saro_0803 comprising four aromatic residues that are crucial to maintaining the resveratrol binding capability of the transcriptional factor. Our data are beneficial to understanding saro_0803′s structural and functional properties, and could provide theoretical clues for future adaptations of this transcriptional factor.

The ongoing pandemic of severe acute respiratory coronavirus 2 (SARS-CoV-2) is causing a devastating impact on public health worldwide. However, details concerning the profound impact of SARS-CoV-2 on host cells remain elusive. Here, we investigated the effects of SARS-CoV-2-encoded viral proteins on the intracellular activity of long interspersed element 1 (L1) retrotransposons using well-established reporter systems. Several nonstructural or accessory proteins (Nsps) of SARS-CoV-2 (i.e., Nsp1, Nsp3, Nsp5, and Nsp14) significantly suppress human L1 mobility, and these viral L1 inhibitors generate a complex network that modulates L1 transposition. Specifically, Nsp1 and Nsp14 inhibit the intracellular accumulation of L1 open reading frame proteins (ORF1p), whereas Nsp3, Nsp5, and Nsp14 repress the reverse transcriptase activity of L1 ORF2p. Given recent findings concerning the roles of L1 in antiviral immune activation and host genome instability, the anti-L1 activities mediated by SARS-CoV-2-encoded inhibitors suggest that SARS-CoV-2 employs different strategies to optimize the host genetic environment.

Ozone (O3) is an important urban air pollutant having strong correlations with respiratory diseases. Several lines of evidence suggest that O3 exposure causes airway hyperresponsiveness (AHR) and pulmonary inflammation. Inhibitory innate immune receptors, such as NLRP12, have been demonstrated to alleviate inflammation, but the functional role for NLRP12 in O3-induced lung inflammatory inflammation remains to be reported. Here, we determined whether NLRP12 took a protective role in O3-induced AHR and pulmonary inflammation via the suppression of canonical NF-κB. C57BL/6 J mice were exposed to filtered air (FA) or 0.25, 0.50 and 1.00 ppm (3 h/day for 5 consecutive days) followed by detection of airway resistance, white blood cells, total proteins, and cytokines. Meanwhile, NLRP12 in lung tissue were detected by real time PCR. Moreover, we also examined protein expression of NLRP12 and key biomarkers of NF-κB pathway. It was shown that 24 h post O3 exposure, AHR as wells as total cells, proteins, and cytokines contents in BALF of mice were increased compare to those of FA controls in a dose-dependent manner. Notably, O3-induced AHR and lung inflammation were associated with significant decrease in pulmonary NLRP12 and upregulation of phosphorylated IRAK1, p65 and IκBα in canonical NF-κB pathway. Intratracheal administration of NLRP12-overexpresing adenovirus 4 days prior to O3 exposure alleviated AHR and lung inflammation, and inhibited canonical NF-κB pathway activation. The findings from this study indicate that NLRP12 attenuates O3-induced AHR and pulmonary inflammation, possibly through regulating canonical NF-κB pathway. This provides a novel target for the prevention and treatment of lung diseases induced by O3 exposure.

Tobacco is a cash crop throughout the world, and its growth and development are affected by abiotic stresses including drought stress; therefore, drought-tolerant breeding may help to improve tobacco yield and quality under drought stress conditions. Considering that the plant hormone ABA (abscisic acid) is able to regulate plant responses to abiotic stresses via activating ABA response genes, the characterization of ABA response genes may enable the identification of genes that can be used for molecular breeding to improve drought tolerance in tobacco. We report here the identification of NtAITRs (Nicotiana tabacum ABA-induced transcription repressors) as a family of novel regulators of drought tolerance in tobacco. Bioinformatics analysis shows that there are a total of eight NtAITR genes in tobacco, and all the NtAITRs have a partially conserved LxLxL motif at their C-terminus. RT-PCR results show that the expression levels of at least some NtAITRs were increased in response to ABA and drought treatments, and NtAITRs, when recruited to the Gal4 promoter via a fused GD (Gal4 DNA-binding domain), were able to repress transcription activator LD-VP activated expression of the LexA-Gal4-GUS reporter gene. Roles of NtAITRs in regulating drought tolerance in tobacco were analyzed by generating CRISPR/Cas9 gene-edited mutants. A total of three Cas9-free ntaitr12356 quintuple mutants were obtained, and drought treatment assays show that drought tolerance was increased in the ntaitr12356 quintuple mutants. On the other hand, results of seed germination and seedling greening assays show that ABA sensitivity was increased in the ntaitr12356 quintuple mutants, and the expression levels of some ABA signaling key regulator genes were altered in the ntaitr12356-c3 mutant. Taken together, our results suggest that NtAITRs are ABA-responsive genes, and that NtAITRs function as transcription repressors and negatively regulate drought tolerance in tobacco, possibly by affecting plant ABA response via affecting the expression of ABA signaling key regulator genes.

Peroxisomes play essential roles in diverse cellular metabolism functions, and their dynamic homeostasis is maintained through the coordination of peroxisome biogenesis and turnover. Pexophagy, selective autophagic degradation of peroxisomes, is a major mechanism for removing damaged and/or superfluous peroxisomes. Dysregulation of pexophagy impairs the physiological functions of peroxisomes and contributes to the progression of many human diseases. However, the mechanisms and functions of pexophagy in mammalian cells remain largely unknown compared to those in yeast. This review focuses on mammalian pexophagy and aims to advance the understanding of the roles of pexophagy in human health and diseases. Increasing evidence shows that ubiquitination can serve as a signal for pexophagy, and ubiquitin-binding receptors, substrates, and E3 ligases/deubiquitinases involved in pexophagy have been described. Alternatively, pexophagy can be achieved in a ubiquitin-independent manner. We discuss the mechanisms of these ubiquitin-dependent and ubiquitin-independent pexophagy pathways and summarize several inducible conditions currently used to study pexophagy. We highlight several roles of pexophagy in human health and how its dysregulation may contribute to diseases.

Triclocarban (TCC), an antibacterial agent widely used in personal care products, can affect embryonic development. However, the specific molecular mechanism of TCC-induced embryonic developmental damage remains unclear. In this study, TCC exposure was found to increase the expression of tmbim4 gene in zebrafish embryos. The tmbim4 mutant embryos are more susceptible to TCC exposure than wild-type (WT) embryos, with tmbim4 overexpression reducing TCC-induced embryonic death in the former. Exposure of tmbim4 mutant larvae to 400 μg/L TCC substantially increased apoptosis in the hindbrain and eyes. RNA-sequencing of WT and tmbim4 mutant larvae indicated that knockout of the tmbim4 gene in zebrafish affects the autophagy pathway. Abnormalities in autophagy can increase apoptosis and TCC exposure caused abnormal accumulation of autophagosomes in the hindbrain of tmbim4 mutant zebrafish embryos. Pretreatment of TCC-exposed tmbim4 mutant zebrafish embryos with autophagosome formation inhibitors, substantially reduced the mortality of embryos and apoptosis levels. These results indicate that defects in the tmbim4 gene can reduce zebrafish embryo resistance to TCC. Additionally, apoptosis induced by abnormal accumulation of autophagosomes is involved in this process.

PEGylated granulocyte colony-stimulating factor (G-CSF) is a safe alternative to G-CSF to improve chemotherapy-induced neutropenia (CIN). This superiority has resulted in its increased use by physicians; however, the superiority of PEGylated G-CSF for CIN in breast cancer has not been conclusively determined. To assess the superiority of PEGylated G-CSF for CIN in breast cancer in terms of effectiveness and safety via a systematic review and meta-analysis. A literature search in PubMed, Embase, Cochrane Library, and Web of Science was performed for eligible studies published from database inception to December 2019. All studies comparing PEGylated G-CSF and G-CSF for CIN of breast cancer were reviewed. After literature selection, data extraction and quality assessment were performed by two reviewers independently. Meta-analysis was conducted using Revman, version 5.2. Nine randomized controlled trials were finally identified. The publication bias of these studies was acceptable. For the endpoint of effectiveness, analysis of the incidence/duration of grade ≥ 3 neutropenia, the duration of grade 4 neutropenia, the incidence of febrile neutropenia (FN), and the time to absolute neutrophil count recovery showed no advantage of PEGylated G-CSF over G-CSF for CIN of breast cancer (P > 0.05), with the premise of a sufficient dose of G-CSF according to the guidelines. No significant differences in grade 4 adverse events were observed between the groups (P = 0.29), and PEGylated G-CSF did not increase the incidence of skeletal and/or muscle pain compared with G-CSF (P = 0.32). PEGylated G-CSF was as effective and safe as G-CSF to reduce CIN in breast cancer but did not show an obvious superiority. However, in clinical practice, PEGylated G-CSF has an obvious advantage in terms of convenience, which could improve patient’s quality of life.

Peroxisomes participate in essential cellular metabolic processes, such as oxidation of fatty acids (FAs) and maintenance of reactive oxygen species (ROS) homeostasis. Peroxisomes must communicate with surrounding organelles to exchange information and metabolites. The formation of membrane contact sites (MCSs), where protein-protein or protein-lipid complexes tether the opposing membranes of two organelles, represents an essential means of organelle crosstalk. Peroxisomal MCS (PO-MCS) studies are emerging but are still in the early stages. In this review, we summarize the identified PO-MCSs with the ER, mitochondria, lipid droplets, and lysosomes in mammalian cells and discuss their tethering mechanisms and physiological roles. We also highlight several features of PO-MCSs that may help future studies.

COPII vesicles mediate anterograde ER-Golgi traffic of newly synthesized proteins in nutrient rich conditions. An accumulating body of results indicates that the secretory COPII vesicles can be shifted to the roles in autophagosome formation and selective ER-phagy (autophagy of ER), depending on their specific subunits, in response to environmental stresses. In this mini-review, we summarize and discuss the multifaceted roles of COPII vesicles in autophagy and the underlying molecular mechanisms.