STING induces LUBAC-mediated synthesis of linear ubiquitin chains to stimulate innate immune signaling.

STING activation by cyclic dinucleotides in mammals induces interferon- and NFκB -related gene expression, and the lipidation of LC3B at Golgi membranes. While mechanisms of the interferon response are well understood, the mechanisms of NFκB activation mediated by STING remain unclear. We report that STING activation induces K63- and M1-linked/linear ubiquitin chain formation at LC3B-associated Golgi membranes. Loss of the LUBAC E3 ubiquitin ligase prevents formation of linear, but not K63-linked ubiquitin chains or STING activation and inhibits STING-induced NFκB and IRF3-mediated signaling in monocytic THP1 cells. The proton channel activity of STING is also important for both K63 and linear ubiquitin chain formation, and NFκB- and interferon-related gene expression. Thus, LUBAC synthesis of linear ubiquitin chains regulates STING-mediated innate immune signaling.

Transverse endoplasmic reticulum expansion in hereditary spastic paraplegia corticospinal axons.

Hereditary spastic paraplegias (HSPs) comprise a large group of inherited neurologic disorders affecting the longest corticospinal axons (SPG1-86 plus others), with shared manifestations of lower extremity spasticity and gait impairment. Common autosomal dominant HSPs are caused by mutations in genes encoding the microtubule-severing ATPase spastin (SPAST; SPG4), the membrane-bound GTPase atlastin-1 (ATL1; SPG3A) and the reticulon-like, microtubule-binding protein REEP1 (REEP1; SPG31). These proteins bind one another and function in shaping the tubular endoplasmic reticulum (ER) network. Typically, mouse models of HSPs have mild, later onset phenotypes, possibly reflecting far shorter lengths of their corticospinal axons relative to humans. Here, we have generated a robust, double mutant mouse model of HSP in which atlastin-1 is genetically modified with a K80A knock-in (KI) missense change that abolishes its GTPase activity, whereas its binding partner Reep1 is knocked out. Atl1KI/KI/Reep1-/- mice exhibit early onset and rapidly progressive declines in several motor function tests. Also, ER in mutant corticospinal axons dramatically expands transversely and periodically in a mutation dosage-dependent manner to create a ladder-like appearance, on the basis of reconstructions of focused ion beam-scanning electron microscopy datasets using machine learning-based auto-segmentation. In lockstep with changes in ER morphology, axonal mitochondria are fragmented and proportions of hypophosphorylated neurofilament H and M subunits are dramatically increased in Atl1KI/KI/Reep1-/- spinal cord. Co-occurrence of these findings links ER morphology changes to alterations in mitochondrial morphology and cytoskeletal organization. Atl1KI/KI/Reep1-/- mice represent an early onset rodent HSP model with robust behavioral and cellular readouts for testing novel therapies.

Hereditary spastic paraplegia SPG8 mutations impair CAV1-dependent, integrin-mediated cell adhesion.

Mutations in WASHC5 (also known as KIAA0196) cause autosomal dominant hereditary spastic paraplegia (HSP) type SPG8. WASHC5, commonly called strumpellin, is a core component of the Wiskott-Aldrich syndrome protein and SCAR homolog (WASH) complex that activates actin nucleation at endosomes. Although various other cellular roles for strumpellin have also been described, none account for how SPG8-associated mutations lead to HSP. Here, we identified protein interactors of the WASH complex by immunoprecipitation and mass spectrometry and assessed the functions of strumpellin in cultured cells using both overexpression and RNA interference along with cell-spreading assays to investigate cell adhesion. We uncovered a decrease in CAV1 protein abundance as well as endosomal fission defects resulting from pathogenic SPG8 mutations. CAV1, a key component of caveolae, interacted with strumpellin in cells, and strumpellin inhibited the lysosomal degradation of CAV1. SPG8-associated missense mutations in strumpellin did not rescue endosomal tubulation defects, reduction in CAV1 protein abundance, or integrin-mediated cell adhesion in strumpellin-deficient cells. Mechanistically, we demonstrated that the WASH complex maintained CAV1 and integrin protein amounts by inhibiting their lysosomal degradation through its endosomal actin nucleation activity. In addition, the interaction of strumpellin with CAV1 stimulated integrin recycling, thereby promoting cell adhesion. These findings provide a molecular link between WASHC5 mutations and impairment of CAV1- and integrin-mediated cell adhesion, providing insights into the cellular pathogenesis of SPG8.

Atlastin Endoplasmic Reticulum-Shaping Proteins Facilitate Zika Virus Replication.

The endoplasmic reticulum (ER) is the site for Zika virus (ZIKV) replication and is central to the cytopathic effects observed in infected cells. ZIKV induces the formation of ER-derived large cytoplasmic vacuoles followed by "implosive" cell death. Little is known about the nature of the ER factors that regulate flavivirus replication. Atlastins (ATL1, -2, and -3) are dynamin-related GTPases that control the structure and the dynamics of the ER membrane. We show here that ZIKV replication is significantly decreased in the absence of ATL proteins. The appearance of infected cells is delayed, the levels of intracellular viral proteins and released virus are reduced, and the cytopathic effects are strongly impaired. We further show that ATL3 is recruited to viral replication sites and interacts with the nonstructural viral proteins NS2A and NS2B3. Thus, proteins that shape and maintain the ER tubular network ensure efficient ZIKV replication.IMPORTANCE Zika virus (ZIKV) is an emerging virus associated with Guillain-Barré syndrome, and fetal microcephaly as well as other neurological complications. There is no vaccine or specific antiviral treatment against ZIKV. We found that endoplasmic reticulum (ER)-shaping atlastin proteins (ATL1, -2, and -3), which induce ER membrane fusion, facilitate ZIKV replication. We show that ATL3 is recruited to the viral replication site and colocalize with the viral proteins NS2A and NS2B3. The results provide insights into host factors used by ZIKV to enhance its replication.

RETRACTED: Human Suicide, Modern Diagnosis Assistance and Magic Bullet Discovery

The article entitled "Human Suicide, Modern Diagnosis Assistance and Magic Bullet Discovery", by Da-Yong Lu, Peng- Peng Zhu, Hong-Ying Wu, Nagendra Sastry Yarla, Bin Xu, Jian Ding, Ajit Varki and Ting-Ren Lu, has been retracted on the request of the co-authors, Dr. Ajit Varki, Dr. Nagendra Sastry Yarla and Dr. Jian Ding available at: Cent Nerv Syst Agents Med Chem 2019; 19(1): 15-23. http://www.eurekaselect.com/169003/article.The Corresponding Author Dr. Da-Yong Lu has included the names of the co-authors, Dr. Ajit Varki, Dr. Nagendra Sastry Yarla and Dr. Jian Ding without their consent and the manuscript has been published in the journal, Central Nervous System Agents in Medicinal Chemistry (CNSAMC). Kindly see Bentham Science Policy on Article retraction at the link given below:(https://benthamscience.com/journals/central-nervous-system-agents-in-medicinal-chemistry/author-guidelines/)Submission of a manuscript to the respective journals implies that all authors have read and agreed to the content of the Copyright Letter or the Terms and Conditions. As such, this article represents a severe abuse of the scientific publishing system. Bentham Science Publishers takes a very strong view on this matter and apologizes to the readers of the journal for any inconvenience this may cause.

Human Suicide Risk and Treatment Study.

INTRODUCTION: Suicide is still a major event of human mortality worldwide. Yet human suicide prediction, prevention and therapeutic systems at this moment are generally ineffective in the clinic. No diagnostic system is reliable for significantly suicidal prevention and mortality reduction. As a result, human suicide etiopathologic investigation (especially at genetic/molecular levels in the clinical settings) is quite necessary. In order to boost human suicide researches, emerging human suicide diagnostic/treatment study will be transformed from clinical symptom observations into new generations of candidate drug targets and therapeutics. To achieve this goal, associations between suicidal etiopathologic identification, genetic/bioinformatics-based diagnostics and putative drug targets must be exploited than ever before. After all, the interaction and relationships between environmental/ genetic/molecular clues and overall patient's risk prediction (environmental influences and different therapeutic targets/types) should be found out. CONCLUSION: In the future, effective clinical suicide prediction, prevention and therapeutic systems can be established via scientific expeditions and causality discovery.

Mammalian knock out cells reveal prominent roles for atlastin GTPases in ER network morphology.

Atlastins are large, membrane-bound GTPases that participate in the fusion of endoplasmic reticulum (ER) tubules to generate the polygonal ER network in eukaryotes. They also regulate lipid droplet size and inhibit bone morphogenetic protein (BMP) signaling, though mechanisms remain unclear. Humans have three atlastins (ATL1, ATL2, and ATL3), and ATL1 and ATL3 are mutated in autosomal dominant hereditary spastic paraplegia and hereditary sensory neuropathies. Cellular investigations of atlastin orthologs in most yeast, plants, flies and worms are facilitated by the presence of a single or predominant isoform, but loss-of-function studies in mammalian cells are complicated by multiple, broadly-expressed paralogs. We have generated mouse NIH-3T3 cells lacking all three mammalian atlastins (Atl1/2/3) using CRISPR/Cas9-mediated gene knockout (KO). ER morphology is markedly disrupted in these triple KO cells, with prominent impairment in formation of three-way ER tubule junctions. This phenotype can be rescued by expression of distant orthologs from Saccharomyces cerevisiae (Sey1p) and Arabidopsis (ROOT HAIR DEFECTIVE3) as well as any one of the three human atlastins. Minimal, if any, changes are observed in the morphology of mitochondria and the Golgi apparatus. Alterations in BMP signaling and increased sensitivity to ER stress are also noted, though effects appear more modest. Finally, atlastins appear required for the proper differentiation of NIH-3T3 cells into an adipocyte-like phenotype. These findings have important implications for the pathogenesis of hereditary spastic paraplegias and sensory neuropathies associated with atlastin mutations.

The Suicidal Risks and Treatments, Seek Medications from Multi-disciplinary.

Suicide events and episodes are serious human psychiatric disorders affected by a great number of different environmental/economic factors, early trauma/abuse, human bad living habits, human genomic properties and drug intervention decisions. In order to improve antidepressant therapeutics in clinics, the relationships between efficacy and toxicities of antidepressants have to be considered fundamentally. Since the occurrences and risks of suicidal events or episodes come from interplay between insiders (chemical/genomic/bioinformatics factors) and outsiders (economic/social/ previous trauma conditions and so on), new perspectives and scientific studies must be implemented for revealing these interrelated factors step-by-step and updating therapeutics in human beings. New paradigms and clinical strategies -joint-expert groups and clinical practices (a psychiatrist with other field specialists) should be established for individual patients in future. Thus can some improvements in clinical trials be achieved in a long run?

High level of intercellular adhesion molecule-1 affects prognosis of patients with hepatocellular carcinoma.

AIM: To determine the cut-off value of intercellular adhesion molecule-1 (ICAM-1) and assess the correlation of ICAM-1 with clinicopathological features and the prognosis of hepatocellular carcinoma (HCC) patients who underwent surgical resection. METHODS: We prospectively collected clinicopathological data from 236 HCC patients who had undergone successful hepatectomy. Receiver operating characteristic curve analysis was performed to determine the optimal cut-off value of ICAM-1. Enzyme-linked immunosorbent assay was used to measure the concentration of ICAM-1 in 236 serum samples isolated from HCC patients and the stratified analysis was used to compare the serum level of ICAM-1 in different HCC subgroups. Immunohistochemistry was performed to test the expression level of the ICAM-1 protein in 76 cases of HCC tissues and their adjacent normal liver tissues (ANLT). The survival probability of HCC patients was estimated using Kaplan-Meier plots and differences between the groups were obtained using the log-rank test. Furthermore, independent indicators of the prognosis were acquired using a stepwise Cox proportional hazard model to analyze a series of predictors that were associated with disease-free survival (DFS) and overall survival (OS) in HCC patients. RESULTS: Our findings suggested that ICAM-1 promotes HCC metastasis and high serum ICAM-1 is significantly associated with alpha-fetoprotein (AFP) (P = 0.022), clinical tumor-node-metastasis stage (P < 0.001), portal vein tumor thrombus (P = 0.005), distant metastasis (P = 0.016) and recurrence (P = 0.034). We further detected the ICAM-1 protein in HCC specimens and found that 56 of 76 (73.7%) HCC tissues had ICAM-1 positive staining while only 23 of 76 (30.3%) ANLT were positively stained (P < 0.0001). Survival analysis indicated that HCC patients with increased ICAM-1 concentrations had significantly shorter DFS and OS after resection. A multivariate analysis showed that ICAM-1 > 684 ng/mL was an independent factor for DFS (HR = 1.643; 95%CI: 1.125-2.401; P = 0.010) and OS (HR = 1.692; 95%CI: 1.152-2.486; P = 0.007). CONCLUSION: ICAM-1 may be a promising serological biomarker for HCC diagnosis and an independent predictor of DFS and OS after surgical resection and may provide a useful reference for the prediction of intra- and extrahepatic metastasis.

The Efficacies and Toxicities of Antidepressant Drugs in Clinics, Building the Relationship between Chemo-Genetics and Socio-Environments.

Antidepressants generally relief human depressive symptoms and help depressed people. Nevertheless, some undesired clinical events, such as suicide have been emerging more recently. In order to improve and promote antidepressant utilizations in clinics, new researches are focusing on reevaluation of the relationship between efficacy and toxicities of antidepressants in China and US. These researches speed up quickly. Many creative ideas and discoveries have been made, including predictions of the efficacies and toxicities of antidepressants under the same evaluating systems (pharmacogenetics and bioinformatics), genome-wide associate study (GWAS) of the relationship between individual genetic factors and therapeutic outcomes of different types of antidepressants and socio-environmental factors. Hopefully, therapeutic efficacies and outcomes by different types of antidepressant treatments for patients can be improved in clinical trials in the near future.

Pharmacologic rescue of axon growth defects in a human iPSC model of hereditary spastic paraplegia SPG3A.

Hereditary spastic paraplegias are a large, diverse group of neurological disorders (SPG1-71) with the unifying feature of prominent lower extremity spasticity, owing to a length-dependent axonopathy of corticospinal motor neurons. The most common early-onset form of pure, autosomal dominant hereditary spastic paraplegia is caused by mutation in the ATL1 gene encoding the atlastin-1 GTPase, which mediates homotypic fusion of ER tubules to form the polygonal ER network. We have identified a p.Pro342Ser mutation in a young girl with pure SPG3A. This residue is in a critical hinge region of atlastin-1 between its GTPase and assembly domains, and it is conserved in all known eukaryotic atlastin orthologs. We produced induced pluripotent stem cells from skin fibroblasts and differentiated these into forebrain neurons to generate a human neuronal model for SPG3A. Axons of these SPG3A neurons showed impaired growth, recapitulating axonal defects in atlastin-1-depleted rat cortical neurons and impaired root hair growth in loss-of-function mutants of the ATL1 ortholog rhd3 in the plant Arabidopsis. Both the microtubule cytoskeleton and tubular ER are important for mitochondrial distribution and function within cells, and SPG3A neurons showed alterations in mitochondrial motility. Even so, it is not clear whether this change is involved in disease pathogenesis. The SPG3A axon growth defects could be rescued with microtubule-binding agents, emphasizing the importance of tubular ER interactions with the microtubule cytoskeleton in hereditary spastic paraplegia pathogenesis. The prominent alterations in axon growth in SPG3A neurons may represent a particularly attractive target for suppression in screens for novel pharmacologic agents.

Genetic and bioinformatic studies of antidepressant drug therapeutic efficacy and toxicity: a current overview.

Antidepressants can relief human depression and reduce human depressive symptoms. Nevertheless, some undesired clinical events, such as suicide have been emerging. As for 2004, the US and European regulatory agencies began implementing verification programs to assess the influence on suicidal behavior from the use of antidepressants such as selective serotonin reuptake inhibitors (SSRIs). With the increasing number of reported cases, several newly developed antidepressants were faced with withdrawal from the markets. Despite unclear cause of suicide, researches focusing on revealing the relationship between efficacy and toxicities of antidepressants have been initiated in China and US. To deal with these undesired clinical consequences, new initiatives and revolutionary ideas have been proposed and verified. Hopefully, therapeutic efficacies and outcomes by different types of antidepressant treatments can be improved for clinical trials in future.

Hereditary spastic paraplegia type 43 (SPG43) is caused by mutation in C19orf12.

We report here the genetic basis for a form of progressive hereditary spastic paraplegia (SPG43) previously described in two Malian sisters. Exome sequencing revealed a homozygous missense variant (c.187G>C; p.Ala63Pro) in C19orf12, a gene recently implicated in neurodegeneration with brain iron accumulation (NBIA). The same mutation was subsequently also found in a Brazilian family with features of NBIA, and we identified another NBIA patient with a three-nucleotide deletion (c.197_199del; p.Gly66del). Haplotype analysis revealed that the p.Ala63Pro mutations have a common origin, but MRI scans showed no brain iron deposition in the Malian SPG43 subjects. Heterologous expression of these SPG43 and NBIA variants resulted in similar alterations in the subcellular distribution of C19orf12. The SPG43 and NBIA variants reported here as well as the most common C19orf12 missense mutation reported in NBIA patients are found within a highly conserved, extended hydrophobic domain in C19orf12, underscoring the functional importance of this domain.

Genetics in neural toxicities of drugs.

Adverse side effects or toxicities of a drug were previously regarded as a manifestation of drug's own characterizations, such as the chemical structure and property of a drug. More recently, increasing experimental or clinical data and modern ideas suggest that human's genetic factors also play indispensable roles in resulting neural side effects of a drug, especially in antidepressant-induced suicide and antibiotics-induced hearing loss. However, there are many questions and technological obstacles (including high costs and limited samples) in these kinds of researches and this makes genetic study of drug toxicities in its initial stage. In this review, we in depth address and analysis of this matter from some new perspectives and propose some new initiatives to improve this type of researches in future. It is also highly needed to expedite the translation of these pharmacogenetic concepts from bench to bedside.

Targeted high-throughput sequencing identifies mutations in atlastin-1 as a cause of hereditary sensory neuropathy type I.

Hereditary sensory neuropathy type I (HSN I) is an axonal form of autosomal-dominant hereditary motor and sensory neuropathy distinguished by prominent sensory loss that leads to painless injuries. Unrecognized, these can result in delayed wound healing and osteomyelitis, necessitating distal amputations. To elucidate the genetic basis of an HSN I subtype in a family in which mutations in the few known HSN I genes had been excluded, we employed massive parallel exon sequencing of the 14.3 Mb disease interval on chromosome 14q. We detected a missense mutation (c.1065C>A, p.Asn355Lys) in atlastin-1 (ATL1), a gene that is known to be mutated in early-onset hereditary spastic paraplegia SPG3A and that encodes the large dynamin-related GTPase atlastin-1. The mutant protein exhibited reduced GTPase activity and prominently disrupted ER network morphology when expressed in COS7 cells, strongly supporting pathogenicity. An expanded screen in 115 additional HSN I patients identified two further dominant ATL1 mutations (c.196G>C [p.Glu66Gln] and c.976 delG [p.Val326TrpfsX8]). This study highlights an unexpected major role for atlastin-1 in the function of sensory neurons and identifies HSN I and SPG3A as allelic disorders.

Undesired neural side-effects of a drug, a chemical and genetic interrelated problem.

Undesired side-effects and toxicities of drugs, especially in the area of new-drug development, are negligibleless, unpredicable and often disastrous once being encountered. Increasing varieties of evidence suggest that the differences of chemical structures of drugs and human's genomic makeup and environmental causes totally decide the occurrences of side-effects and toxicities of drugs instead of chemical structures of a drug alone. The side-effects of central neural systems are relatively easy to be observed and conspicuous and sensitive to judgments with or by fixed grading systems. It could be an important area to systematically study the side-effects of drugs and underlying genetic mechanisms and relationships in between. This review discusses this issue through careful analyzing relevant clinical evidence and published data relating to genetic detection of suffered patients and gives further suggestions to improve.

Hereditary spastic paraplegia proteins REEP1, spastin, and atlastin-1 coordinate microtubule interactions with the tubular ER network.

Hereditary spastic paraplegias (HSPs; SPG1-45) are inherited neurological disorders characterized by lower extremity spastic weakness. More than half of HSP cases result from autosomal dominant mutations in atlastin-1 (also known as SPG3A), receptor expression enhancing protein 1 (REEP1; SPG31), or spastin (SPG4). The atlastin-1 GTPase interacts with spastin, a microtubule-severing ATPase, as well as with the DP1/Yop1p and reticulon families of ER-shaping proteins, and SPG3A caused by atlastin-1 mutations has been linked pathogenically to abnormal ER morphology. Here we investigated SPG31 by analyzing the distribution, interactions, and functions of REEP1. We determined that REEP1 is structurally related to the DP1/Yop1p family of ER-shaping proteins and localizes to the ER in cultured rat cerebral cortical neurons, where it colocalizes with spastin and atlastin-1. Upon overexpression in COS7 cells, REEP1 formed protein complexes with atlastin-1 and spastin within the tubular ER, and these interactions required hydrophobic hairpin domains in each of these proteins. REEP proteins were required for ER network formation in vitro, and REEP1 also bound microtubules and promoted ER alignment along the microtubule cytoskeleton in COS7 cells. A SPG31 mutant REEP1 lacking the C-terminal cytoplasmic region did not interact with microtubules and disrupted the ER network. These data indicate that the HSP proteins atlastin-1, spastin, and REEP1 interact within the tubularER membrane in corticospinal neurons to coordinate ER shaping and microtubule dynamics. Thus, defects in tubular ER shaping and network interactions with the microtubule cytoskeleton seem to be the predominant pathogenic mechanism of HSP.

A class of dynamin-like GTPases involved in the generation of the tubular ER network.

The endoplasmic reticulum (ER) consists of tubules that are shaped by the reticulons and DP1/Yop1p, but how the tubules form an interconnected network is unknown. Here, we show that mammalian atlastins, which are dynamin-like, integral membrane GTPases, interact with the tubule-shaping proteins. The atlastins localize to the tubular ER and are required for proper network formation in vivo and in vitro. Depletion of the atlastins or overexpression of dominant-negative forms inhibits tubule interconnections. The Sey1p GTPase in S. cerevisiae is likely a functional ortholog of the atlastins; it shares the same signature motifs and membrane topology and interacts genetically and physically with the tubule-shaping proteins. Cells simultaneously lacking Sey1p and a tubule-shaping protein have ER morphology defects. These results indicate that formation of the tubular ER network depends on conserved dynamin-like GTPases. Since atlastin-1 mutations cause a common form of hereditary spastic paraplegia, we suggest ER-shaping defects as a neuropathogenic mechanism.

Atlastin GTPases are required for Golgi apparatus and ER morphogenesis.

The hereditary spastic paraplegias (SPG1-33) comprise a cluster of inherited neurological disorders characterized principally by lower extremity spasticity and weakness due to a length-dependent, retrograde axonopathy of corticospinal motor neurons. Mutations in the gene encoding the large oligomeric GTPase atlastin-1 are responsible for SPG3A, a common autosomal dominant hereditary spastic paraplegia. Here we describe a family of human GTPases, atlastin-2 and -3 that are closely related to atlastin-1. Interestingly, while atlastin-1 is predominantly localized to vesicular tubular complexes and cis-Golgi cisternae, mostly in brain, atlastin-2 and -3 are localized to the endoplasmic reticulum (ER) and are most enriched in other tissues. Knockdown of atlastin-2 and -3 levels in HeLa cells using siRNA (small interfering RNA) causes disruption of Golgi morphology, and these Golgi structures remain sensitive to brefeldin A treatment. Interestingly, expression of SPG3A mutant or dominant-negative atlastin proteins lacking GTPase activity causes prominent inhibition of ER reticularization, suggesting a role for atlastin GTPases in the formation of three-way junctions in the ER. However, secretory pathway trafficking as assessed using vesicular stomatitis virus G protein fused to green fluorescent protein (VSVG-GFP) as a reporter was essentially normal in both knockdown and dominant-negative overexpression conditions for all atlastins. Thus, the atlastin family of GTPases functions prominently in both ER and Golgi morphogenesis, but they do not appear to be required generally for anterograde ER-to-Golgi trafficking. Abnormal morphogenesis of the ER and Golgi resulting from mutations in atlastin-1 may ultimately underlie SPG3A by interfering with proper membrane distribution or polarity of the long corticospinal motor neurons.