CXCR5(+) follicular cytotoxic T cells control viral infection in B cell follicles.

During unresolved infections, some viruses escape immunological control and establish a persistant reservoir in certain cell types, such as human immunodeficiency virus (HIV), which persists in follicular helper T cells (TFH cells), and Epstein-Barr virus (EBV), which persists in B cells. Here we identified a specialized group of cytotoxic T cells (TC cells) that expressed the chemokine receptor CXCR5, selectively entered B cell follicles and eradicated infected TFH cells and B cells. The differentiation of these cells, which we have called 'follicular cytotoxic T cells' (TFC cells), required the transcription factors Bcl6, E2A and TCF-1 but was inhibited by the transcriptional regulators Blimp1, Id2 and Id3. Blimp1 and E2A directly regulated Cxcr5 expression and, together with Bcl6 and TCF-1, formed a transcriptional circuit that guided TFC cell development. The identification of TFC cells has far-reaching implications for the development of strategies to control infections that target B cells and TFH cells and to treat B cell-derived malignancies.

The RNA m6A reader YTHDC1 silences retrotransposons and guards ES cell identity.

The RNA modification N6-methyladenosine (m6A) has critical roles in many biological processes1,2. However, the function of m6A in the early phase of mammalian development remains poorly understood. Here we show that the m6A reader YT521-B homology-domain-containing protein 1 (YTHDC1) is required for the maintenance of mouse embryonic stem (ES) cells in an m6A-dependent manner, and that its deletion initiates cellular reprogramming to a 2C-like state. Mechanistically, YTHDC1 binds to the transcripts of retrotransposons (such as intracisternal A particles, ERVK and LINE1) in mouse ES cells and its depletion results in the reactivation of these silenced retrotransposons, accompanied by a global decrease in SETDB1-mediated trimethylation at lysine 9 of histone H3 (H3K9me3). We further demonstrate that YTHDC1 and its target m6A RNAs act upstream of SETDB1 to repress retrotransposons and Dux, the master inducer of the two-cell stage (2C)-like program. This study reveals an essential role for m6A RNA and YTHDC1 in chromatin modification and retrotransposon repression.

Nanoinjection: A Platform for Innovation in Ex Vivo Cell Engineering.

ConspectusIn human cells, intracellular access and therapeutic cargo transport, including gene-editing tools (e.g., CRISPR-Cas9 and transposons), nucleic acids (e.g., DNA, mRNA, and siRNA), peptides, and proteins (e.g., enzymes and antibodies), are tightly constrained to ensure healthy cell function and behavior. This principle is exemplified in the delivery mechanisms of chimeric antigen receptor (CAR)-T cells for ex-vivo immunotherapy. In particular, the clinical success of CAR-T cells has established a new standard of care by curing previously incurable blood cancers. The approach involves the delivery, typically via the use of electroporation (EP) and lentivirus, of therapeutic CAR genes into a patient's own T cells, which are then engineered to express CARs that target and combat their blood cancer. But the key difficulty lies in genetically manipulating these cells without causing irreversible damage or loss of function─all the while minimizing complexities of manufacturing, safety concerns, and costs, and ensuring the efficacy of the final CAR-T cell product.Nanoinjection─the process of intracellular delivery using nanoneedles (NNs)─is an emerging physical delivery route that efficiently negotiates the plasma membrane of many cell types, including primary human T cells. It occurs with minimal perturbation, invasiveness, and toxicity, with high efficiency and throughput at high spatial and temporal resolutions. Nanoinjection promises greatly improved delivery of a broad range of therapeutic cargos with little or no damage to those cargos. A nanoinjection platform allows these cargos to function in the intracellular space as desired. The adaptability of nanoinjection platforms is now bringing major advantages in immunomodulation, mechanotransduction, sampling of cell states (nanobiopsy), controlled intracellular interrogation, and the primary focus of this account─intracellular delivery and its applications in ex vivo cell engineering.Mechanical nanoinjection typically exerts direct mechanical force on the cell membrane, offering a straightforward route to improve membrane perturbation by the NNs and subsequent transport of genetic cargo into targeted cell type (adherent or suspension cells). By contrast, electroactive nanoinjection is controlled by coupling NNs with an electric field─a new route for activating electroporation (EP) at the nanoscale─allowing a dramatic reduction of the applied voltage to a cell and so minimizing post-EP damage to cells and cargo, and overcoming many of the limitations of conventional bulk EP. Nanoinjection transcends mere technique; it is an approach to cell engineering ex vivo, offering the potential to endow cells with new, powerful features such as generating chimeric antigen receptor (CAR)-T cells for future CAR-T cell technologies.We first discuss the manufacturing of NN devices (Section 2), then delve into nanoinjection-mediated cell engineering (Section 3), nanoinjection mechanisms and interfacing methodologies (Section 4), and emerging applications in using nanoinjection to create functional CAR-T cells (Section 5).

Epitope screening and vaccine molecule design of PRRSV GP3 and GP5 protein based on immunoinformatics.

Porcine reproductive and respiratory syndrome (PRRS) is a respiratory disease in pigs that causes severe economic losses. Currently, live PRRSV vaccines are commonly used but fail to prevent PRRS outbreaks and reinfection. Inactivated PRRSV vaccines have poor immunogenicity, making PRRSV a significant threat to swine health globally. Therefore, there is an urgent need to develop an effective PRRSV vaccine. This study used immunoinformatics to predict, screen, design and construct a candidate vaccine that fused B-cell epitopes, CTL- and HTL-dominant protective epitopes of PRRSV strain's GP3 and GP5 proteins. The study identified 12 B-cell epitopes, 6 CTL epitopes and 5 HTL epitopes of GP3 and GP5 proteins. The candidate vaccine was constructed with 50S ribosomal protein L7/L1 molecular adjuvant, which has antigenicity, solubility, stability, non-allergenicity and a high affinity for its target receptor, TLR-3. The C-ImmSim immunostimulation results showed significant increases in cellular and humoral responses (B cells and T cells) and production of TGF-ß, IL-2, IL-10, IFN-γ and IL-12. The constructed vaccine was stable and immunogenic, and it can effectively induce strong T-cell and B-cell immune responses against PRRSV. Therefore, it is a promising candidate vaccine for controlling and preventing PRRSV outbreaks.

Unveiling a novel serpinB2-tripeptidyl peptidase II signaling axis during senescence.

Tripeptidyl peptidase II (TPPII or TPP2) degrades N-terminal tripeptides from proteins and peptides. Studies in both humans and mice have shown that TPPII deficiency is linked to cellular immune-senescence, lifespan regulation and the aging process. However, the mechanism of how TPPII participates in these processes is less clear. In this study, we established a chemical probe-based assay and found that although the mRNA and protein levels of TPPII were not altered during senescence, its enzymatic activity was reduced in senescent human fibroblasts. We also showed that elevation of the levels of the serine protease inhibitor serpinB2 reduced TPPII activity in senescent cells. Moreover, suppression of TPPII led to elevation in the amount of lysosomal contents as in well as TPPI (TPP1) and ß-galactosidase activities, suggesting that lysosome biogenesis is induced to compensate for the reduction of TPPII activity in senescent cells. Together, this study discloses a critical role of the serpinB2-TPPII signaling pathway in proteostasis during senescence. Since serpinB2 levels can be increased by a variety of cellular stresses, reduction of TPPII activity through activation of serpinB2 might represent a common pathway for cells to respond to different stress conditions. This article has an associated First Person interview with the first author of the paper.

Upland forest retreat lags behind sea-level rise in the mid-Atlantic coast.

Ghost forests consisting of dead trees adjacent to marshes are striking indicators of climate change, and marsh migration into retreating coastal forests is a primary mechanism for marsh survival in the face of global sea-level rise. Models of coastal transgression typically assume inundation of a static topography and instantaneous conversion of forest to marsh with rising seas. In contrast, here we use four decades of satellite observations to show that many low-elevation forests along the US mid-Atlantic coast have survived despite undergoing relative sea-level rise rates (RSLRR) that are among the fastest on Earth. Lateral forest retreat rates were strongly mediated by topography and seawater salinity, but not directly explained by spatial variability in RSLRR, climate, or disturbance. The elevation of coastal tree lines shifted upslope at rates correlated with, but far less than, contemporary RSLRR. Together, these findings suggest a multi-decadal lag between RSLRR and land conversion that implies coastal ecosystem resistance. Predictions based on instantaneous conversion of uplands to wetlands may therefore overestimate future land conversion in ways that challenge the timing of greenhouse gas fluxes and marsh creation, but also imply that the full effects of historical sea-level rise have yet to be realized.

RNA-Seq Reveals That Multiple Pathways Are Involved in Tuber Expansion in Tiger Nuts (Cyperus esculentus L.).

The tiger nut (Cyperus esculentus L.) is a usable tuber and edible oil plant. The size of the tubers is a key trait that determines the yield and the mechanical harvesting of tiger nut tubers. However, little is known about the anatomical and molecular mechanisms of tuber expansion in tiger nut plants. This study conducted anatomical and comprehensive transcriptomics analyses of tiger nut tubers at the following days after sowing: 40 d (S1); 50 d (S2); 60 d (S3); 70 d (S4); 90 d (S5); and 110 d (S6). The results showed that, at the initiation stage of a tiger nut tuber (S1), the primary thickening meristem (PTM) surrounded the periphery of the stele and was initially responsible for the proliferation of parenchyma cells of the cortex (before S1) and then the stele (S2-S3). The increase in cell size of the parenchyma cells occurred mainly from S1 to S3 in the cortex and from S3 to S4 in the stele. A total of 12,472 differentially expressed genes (DEGs) were expressed to a greater extent in the S1-S3 phase than in S4-S6 phase. DEGs related to tuber expansion were involved in cell wall modification, vesicle transport, cell membrane components, cell division, the regulation of plant hormone levels, signal transduction, and metabolism. DEGs involved in the biosynthesis and the signaling of indole-3-acetic acid (IAA) and jasmonic acid (JA) were expressed highly in S1-S3. The endogenous changes in IAA and JAs during tuber development showed that the highest concentrations were found at S1 and S1-S3, respectively. In addition, several DEGs were related to brassinosteroid (BR) signaling and the G-protein, MAPK, and ubiquitin-proteasome pathways, suggesting that these signaling pathways have roles in the tuber expansion of tiger nut. Finally, we come to the conclusion that the cortex development preceding stele development in tiger nut tubers. The auxin signaling pathway promotes the division of cortical cells, while the jasmonic acid pathway, brassinosteroid signaling, G-protein pathway, MAPK pathway, and ubiquitin protein pathway regulate cell division and the expansion of the tuber cortex and stele. This finding will facilitate searches for genes that influence tuber expansion and the regulatory networks in developing tubers.

Speech intelligibility changes the temporal evolution of neural speech tracking.

Listening to speech with poor signal quality is challenging. Neural speech tracking of degraded speech has been used to advance the understanding of how brain processes and speech intelligibility are interrelated. However, the temporal dynamics of neural speech tracking and their relation to speech intelligibility are not clear. In the present MEG study, we exploited temporal response functions (TRFs), which has been used to describe the time course of speech tracking on a gradient from intelligible to unintelligible degraded speech. In addition, we used inter-related facets of neural speech tracking (e.g., speech envelope reconstruction, speech-brain coherence, and components of broadband coherence spectra) to endorse our findings in TRFs. Our TRF analysis yielded marked temporally differential effects of vocoding: ∼50-110 ms (M50TRF), ∼175-230 ms (M200TRF), and ∼315-380 ms (M350TRF). Reduction of intelligibility went along with large increases of early peak responses M50TRF, but strongly reduced responses in M200TRF. In the late responses M350TRF, the maximum response occurred for degraded speech that was still comprehensible then declined with reduced intelligibility. Furthermore, we related the TRF components to our other neural "tracking" measures and found that M50TRF and M200TRF play a differential role in the shifting center frequency of the broadband coherence spectra. Overall, our study highlights the importance of time-resolved computation of neural speech tracking and decomposition of coherence spectra and provides a better understanding of degraded speech processing.

Low-dose IL-2 therapy invigorates CD8+ T cells for viral control in systemic lupus erythematosus.

Autoimmune diseases are often treated by glucocorticoids and immunosuppressive drugs that could increase the risk for infection, which in turn deteriorate disease and cause mortality. Low-dose IL-2 (Ld-IL2) therapy emerges as a new treatment for a wide range of autoimmune diseases. To examine its influence on infection, we retrospectively studied 665 patients with systemic lupus erythematosus (SLE) including about one third receiving Ld-IL2 therapy, where Ld-IL2 therapy was found beneficial in reducing the incidence of infections. In line with this clinical observation, IL-2 treatment accelerated viral clearance in mice infected with influenza A virus or lymphocytic choriomeningitis virus (LCMV). Noticeably, despite enhancing anti-viral immunity in LCMV infection, IL-2 treatment exacerbated CD8+ T cell-mediated immunopathology. In summary, Ld-IL2 therapy reduced the risk of infections in SLE patients and enhanced the control of viral infection, but caution should be taken to avoid potential CD8+ T cell-mediated immunopathology.

ARIH1 inhibits influenza A virus replication and facilitates RIG-I dependent immune signaling by interacting with SQSTM1/p62.

BACKGROUND: Multiple host factors are involved in modulating type I interferon expression induced by viruses; however, the mechanism is not fully elucidated. Influenza A virus infection causes severe respiratory symptoms and triggers a series of signaling cascades and host innate immune responses, including interferon production. The co-IP/MS technology was used to screen several antiviral factors in the early stage. Among these factors, ariadne-1 homolog (ARIH1) caught our attention. METHODS: Western blot assay was performed to detect the level of proteins and software ImageJ was used to analyze the band intensities. Polymerase activity assay was conducted to evaluate the polymerase activity of influenza A virus. Tissue culture infective dose (TCID50) assay was performed to measure influenza A virus titers, and quantitative RT-PCR assay was applied to test the mRNA level of IFN-ß, ISG56, and CXCL10. Luciferase reporter assay was used to confirm the target of ARIH1 in RIG-I signaling. Immunoprecipitation assay was performed to detect the interaction and the ubiquitination of the proteins. All data were analyzed by biostatistical methods and presented as means ± standard deviation from three independent experiments. Statistical significance was determined using two-tailed student's t test. A P value of less than 0.05 was considered statistically significant, and a P value of less than 0.01 was considered highly significant (ns, P ≥ 0.05; *, P < 0.05; and **, P < 0.01). RESULTS: We found that ARIH1, a member of E3 ubiquitin ligases, enhanced cellular antiviral responses. Subsequent study showed that ARIH1 was up-regulated during influenza A virus infection. Further analysis showed that ARIH1 enhanced IFN-ß and downstream gene expression by affecting the degradation of RIG-I through the SQSTM1/p62 signaling pathway. CONCLUSION: This newly revealed mechanism shows that cellular response increases of ARIH1 and promotes IFN-ß expression to boost host survival during viral infection.

Neural speech tracking shifts from the syllabic to the modulation rate of speech as intelligibility decreases.

The most prominent acoustic features in speech are intensity modulations, represented by the amplitude envelope of speech. Synchronization of neural activity with these modulations supports speech comprehension. As the acoustic modulation of speech is related to the production of syllables, investigations of neural speech tracking commonly do not distinguish between lower-level acoustic (envelope modulation) and higher-level linguistic (syllable rate) information. Here we manipulated speech intelligibility using noise-vocoded speech and investigated the spectral dynamics of neural speech processing, across two studies at cortical and subcortical levels of the auditory hierarchy, using magnetoencephalography. Overall, cortical regions mostly track the syllable rate, whereas subcortical regions track the acoustic envelope. Furthermore, with less intelligible speech, tracking of the modulation rate becomes more dominant. Our study highlights the importance of distinguishing between envelope modulation and syllable rate and provides novel possibilities to better understand differences between auditory processing and speech/language processing disorders.

Omicron variant of SARS-COV-2 in Shanghai: Clinical features and inactivated vaccine efficacy in 13,120 elderly patients.

Background: Few reports concerning inactivated vaccine efficacy in elderly patients with Omicron infection. We aimed at demonstrating the clinical characteristics of elderly patients with mild disease and assessing the protective effect of the vaccine preliminarily. Methods: 13,120 mild patients who aged beyond 60 years old were included in this study totally, medical records were collected and analyzed. Results: Patients beyond 60 years had more chronic comorbidities, significantly lower ORF1ab and N gene CT values, and longer time of nucleic acid conversion than other age groups. Higher CT value of ORF1ab and N gene were found in older patients who received a booster dose of vaccine than in those who received two doses. The time of nucleic acid conversion was longest in unvaccinated old patients, with a decreasing trend from those who received two doses to those who received a booster doses. We also used random forest and logistic regression to screen for factors strongly associated with nucleic acid conversion and to predict the time of nucleic acid conversion. Conclusion: For mild patients with Omicron infection, patients aged>60 years had mild clinical symptoms, higher viral loads, and longer time of nucleic acid conversion, when compared with younger patients. The inactivated SARS-CoV-2 vaccine provided effective protection among adults with omicron variant infection, and the effectiveness of three doses of the vaccine was greater than that of two doses of the vaccine. Special attention should be given to elderly patients.

Electroactive nanoinjection platform for intracellular delivery and gene silencing.

BACKGROUND: Nanoinjection-the process of intracellular delivery using vertically configured nanostructures-is a physical route that efficiently negotiates the plasma membrane, with minimal perturbation and toxicity to the cells. Nanoinjection, as a physical membrane-disruption-mediated approach, overcomes challenges associated with conventional carrier-mediated approaches such as safety issues (with viral carriers), genotoxicity, limited packaging capacity, low levels of endosomal escape, and poor versatility for cell and cargo types. Yet, despite the implementation of nanoinjection tools and their assisted analogues in diverse cellular manipulations, there are still substantial challenges in harnessing these platforms to gain access into cell interiors with much greater precision without damaging the cell's intricate structure. Here, we propose a non-viral, low-voltage, and reusable electroactive nanoinjection (ENI) platform based on vertically configured conductive nanotubes (NTs) that allows for rapid influx of targeted biomolecular cargos into the intracellular environment, and for successful gene silencing. The localization of electric fields at the tight interface between conductive NTs and the cell membrane drastically lowers the voltage required for cargo delivery into the cells, from kilovolts (for bulk electroporation) to only ≤ 10 V; this enhances the fine control over membrane disruption and mitigates the problem of high cell mortality experienced by conventional electroporation. RESULTS: Through both theoretical simulations and experiments, we demonstrate the capability of the ENI platform to locally perforate GPE-86 mouse fibroblast cells and efficiently inject a diverse range of membrane-impermeable biomolecules with efficacy of 62.5% (antibody), 55.5% (mRNA), and 51.8% (plasmid DNA), with minimal impact on cells' viability post nanoscale-EP (> 90%). We also show gene silencing through the delivery of siRNA that targets TRIOBP, yielding gene knockdown efficiency of 41.3%. CONCLUSIONS: We anticipate that our non-viral and low-voltage ENI platform is set to offer a new safe path to intracellular delivery with broader selection of cargo and cell types, and will open opportunities for advanced ex vivo cell engineering and gene silencing.

Effects of dual-task training on chronic ankle instability: a systematic review and meta-analysis.

BACKGROUND: Dual-task training has been a popular intervention for individuals with balance impairments. However, the effects of dual-task training on chronic ankle instability (CAI) have not been comprehensively analyzed and reliable clinical evidence is scarce. The purpose of this systematic review and meta-analysis is to evaluate the effectiveness of dual-task training on postural stability and functional ability in individuals with CAI. METHODS: PubMed, Web of Science, EBSCO, Cochrane Library, Physiotherapy Evidence Database (PEDro), and China National Knowledge Infrastructure (CNKI) were researched from inception to November 2022. This study was conducted by the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Two reviewers assessed the studies for inclusion and extracted data. The Cochrane Risk of Bias list was used to assess the risk of bias in included studies. Mean differences (MD) with a 95% confidence interval (CI) were calculated with the RevMan 5.3 software. RESULTS: A total of 7 randomized controlled trials with 192 CAI met the inclusion criteria. The meta-analysis results showed that compared with the control group, dual-task training significantly improved the Y-balance test (MD = 1.60, 95% CI: -0.00 to 3.21, P = 0.050) and reduced COP-area (MD = - 0.94, 95% CI: -1.62 to - 0.26, P = 0.007) in individuals with CAI. However, there is no significant difference between dual-task training and the control group on COP-velocity (MD = - 0.26, 95% CI: -0.70 to 0.17, P = 0.240), hop test (MD = - 0.20, 95% CI: -0.66 to 0.26, P = 0.386) and BESS (MD = - 1.24, 95% CI: -2.95 to 0.48, P = 0.157) in individuals with CAI. CONCLUSION: This meta-analysis showed that dual-task training may be effective in improving static and dynamic postural stability. However, more high-quality randomized controlled trials are needed to verify the short and long-term effectiveness of dual-task training on CAI.

Positive effects of neuromuscular exercises on pain and active range of motion in idiopathic frozen shoulder: a randomized controlled trial.

BACKGROUND AND OBJECTIVES: Frozen shoulder (FS) is characterized by pain and significant loss of active and passive shoulder motion. Strengthening exercises are among the standard exercises used for FS. Neuromuscular exercise (NME) effectively improved pain and the range of motion in shoulder. However, no prior research has looked into the effects of NME compared to strengthening exercises in FS rehabilitation. The aim of the present study was to evaluate the effects of NME compared to strengthening exercises on pain and active range of motion (AROM) in individuals with idiopathic frozen shoulder. METHODS: Forty individuals with idiopathic frozen shoulder were randomly assigned to either the experimental group (NME with regular physical therapy, n = 20) or the control group (strengthening exercises with regular physical therapy, n = 20). In both groups, the interventions were performed once a day, 5 days a week for 8 weeks. Pain scores on the visual analogue scale (VAS) and AROM of the shoulder were assessed at baseline and after the 8-week treatment. The primary analysis was the group × time interaction. RESULTS: Two-by-two mixed analysis of variance (ANOVA) revealed a significant group × time interaction for VAS (F = 29.67; p < 0.01); AROM in flexion (F = 12.05; p < 0.01), internal rotation (F = 6.62; p < 0.05) and external rotation (F = 16.93; p < 0.01) in favor of the experimental group. The two-by-two mixed ANOVA revealed a significant main effect of time for VAS (F = 1648.47; p < 0.01); AROM in flexion (F = 591.70; p < 0.01), extension (F = 114.57; p < 0.01), abduction (F = 1602.04; p < 0.01), internal rotation (F = 664.14; p < 0.01) and external rotation (F = 1096.92; p < 0.01). No other significant differences were found. CONCLUSIONS: NME is superior to strengthening exercises in terms of pain and AROM of shoulder flexion, internal rotation and external rotation in individuals with idiopathic FS. NME could be used to treat individuals with FS. TRIAL REGISTRATION: Trial registration number: ChiCTR2100054453. Registration date: 17/12/2021.

Relationship between ankle pain, range of motion, strength and balance in individuals with functional ankle instability: a cross-sectional study.

BACKGROUND: About 15-60% of individuals with ankle sprains may develop functional ankle instability (FAI), which is characterised by ankle pain, decreased muscle strength, limited range of motion, and impaired balance, causing a decline in social activity and quality of life. However, the relationship between those characters is still unclear. This study aimed to investigate whether a relationship existed between ankle pain, active range of motion (AROM), strength and balance and if ankle pain, AROM and strength can predict balance in individuals with FAI. METHODS: Seventy-seven subjects (46 males; 31 females) with unilateral FAI participated in this study. Ankle pain was measured by the visual analogue scale (VAS), ankle AROM was measured using a universal goniometer, ankle strength was measured using a handheld dynamometer, the static balance was measured by the Time in Balance Test (TBT) and the dynamic balance was measured by the modified Star Excursion Balance Test (mSEBT). Pearson product-moment correlations were used to determine the correlations between ankle pain, AROM, strength and balance. Multiple linear regressions were used to investigate if ankle pain, AROM and strength can predict balance in individuals with FAI. RESULTS: VAS and AROM-plantarflexion predicted 25.6% of the TBT (f2 = 0.344, P < 0.001). AROM-dorsiflexion predicted 24.6% of the mSEBT-anterior reach (f2 = 0.326, P < 0.001). VAS, AROM-plantarflexion and strength-plantarflexion predicted 33.5% of the mSEBT-posteromedial reach (f2 = 0.504, P < 0.001). AROM-plantarflexion and strength-plantarflexion predicted 28.2% of the mSEBT-posterolateral reach (f2 = 0.393, P < 0.001). CONCLUSION: This study shows that ankle plantarflexion strength, AROM of dorsiflexion and plantarflexion and pain are predictors of balance in individuals with FAI. These factors could be considered in the rehabilitation of FAI. TRIAL REGISTRATION: Trial registration number: ChiCTR2200063532.

A Rare Case of Abnormal Hemoglobin Variant Hb Mizuho: [HBB: c.206T > C ß 68(E12) Leu-Pro]: A First Report in the Chinese Population.

A 6-month-old female infant presented with unexplained hemolytic anemia, showing no abnormalities by capillary electrophoresis and genetic testing for α- and ß-thalassemia mutations that are commonly seen in the Chinese population. A rare Hb Mizuho: [HBB: c.206T > C ß 68(E12) Leu- Pro] variant was identified by next-generation sequencing (NGS) and verified by Sanger sequencing. Hb Mizuho: [HBB: c.206T > C ß 68(E12) Leu- Pro] is not easily detectable because it is extremely unstable, and the correct diagnosis is usually made via DNA sequencing. This is the first report of this variant in the Chinese population.

Tracking Adaptive Pathways of Invasive Insects: Novel Insight from Genomics.

Despite the huge human and economic costs of invasive insects, which are the main group of invasive species, their environmental impacts through various mechanisms remain inadequately explained in databases and much of the invasion biology literature. High-throughput sequencing technology, especially whole-genome sequencing, has been used as a powerful method to study the mechanisms through which insects achieve invasion. In this study, we reviewed whole-genome sequencing-based advances in revealing several important invasion mechanisms of invasive insects, including (1) the rapid genetic variation and evolution of invasive populations, (2) invasion history and dispersal paths, (3) rapid adaptation to different host plant ranges, (4) strong environmental adaptation, (5) the development of insecticide resistance, and (6) the synergistic damage caused by invasive insects and endosymbiotic bacteria. We also discussed prevention and control technologies based on whole-genome sequencing and their prospects.

Overexpression of LjPLT3 Enhances Salt Tolerance in Lotus japonicus.

Intracellular polyols are used as osmoprotectants by many plants under environmental stress. However, few studies have shown the role of polyol transporters in the tolerance of plants to abiotic stresses. Here, we describe the expression characteristics and potential functions of Lotus japonicus polyol transporter LjPLT3 under salt stress. Using LjPLT3 promoter-reporter gene plants showed that LjPLT3 was expressed in the vascular tissue of L. japonicus leaf, stem, root, and nodule. The expression was also induced by NaCl treatment. Overexpression of LjPLT3 in L. japonicus modified the growth rate and saline tolerance of the transgenic plants. The OELjPLT3 seedlings displayed reduced plant height under both nitrogen-sufficient and symbiotic nitrogen fixation conditions when 4 weeks old. The nodule number of OELjPLT3 plants was reduced by 6.7-27.4% when 4 weeks old. After exposure to a NaCl treatment in Petri dishes for 10 days, OELjPLT3 seedlings had a higher chlorophyll concentration, fresh weight, and survival rate than those in the wild type. For symbiotic nitrogen fixation conditions, the decrease in nitrogenase activity of OELjPLT3 plants was slower than that of the wild type after salt treatment. Compared to the wild type, both the accumulation of small organic molecules and the activity of antioxidant enzymes were higher under salt stress. Considering the concentration of lower reactive oxygen species (ROS) in transgenic lines, we speculate that overexpression of LjPLT3 in L. japonicus might improve the ROS scavenging system to alleviate the oxidative damage caused by salt stress, thereby increasing plant salinity tolerance. Our results will direct the breeding of forage legumes in saline land and also provide an opportunity for the improvement of poor and saline soils.

Young Leaf White Stripe encodes a P-type PPR protein required for chloroplast development.

Pentatricopeptide repeat (PPR) proteins function in post-transcriptional regulation of organellar gene expression. Although several PPR proteins are known to function in chloroplast development in rice (Oryza sativa), the detailed molecular functions of many PPR proteins remain unclear. Here, we characterized a rice young leaf white stripe (ylws) mutant, which has defective chloroplast development during early seedling growth. Map-based cloning revealed that YLWS encodes a novel P-type chloroplast-targeted PPR protein with 11 PPR motifs. Further expression analyses showed that many nuclear- and plastid-encoded genes in the ylws mutant were significantly changed at the RNA and protein levels. The ylws mutant was impaired in chloroplast ribosome biogenesis and chloroplast development under low-temperature conditions. The ylws mutation causes defects in the splicing of atpF, ndhA, rpl2, and rps12, and editing of ndhA, ndhB, and rps14 transcripts. YLWS directly binds to specific sites in the atpF, ndhA, and rpl2 pre-mRNAs. Our results suggest that YLWS participates in chloroplast RNA group II intron splicing and plays an important role in chloroplast development during early leaf development.