Antibody Lineages with Vaccine-Induced Antigen-Binding Hotspots Develop Broad HIV Neutralization.

The vaccine-mediated elicitation of antibodies (Abs) capable of neutralizing diverse HIV-1 strains has been a long-standing goal. To understand how broadly neutralizing antibodies (bNAbs) can be elicited, we identified, characterized, and tracked five neutralizing Ab lineages targeting the HIV-1-fusion peptide (FP) in vaccinated macaques over time. Genetic and structural analyses revealed two of these lineages to belong to a reproducible class capable of neutralizing up to 59% of 208 diverse viral strains. B cell analysis indicated each of the five lineages to have been initiated and expanded by FP-carrier priming, with envelope (Env)-trimer boosts inducing cross-reactive neutralization. These Abs had binding-energy hotspots focused on FP, whereas several FP-directed Abs induced by immunization with Env trimer-only were less FP-focused and less broadly neutralizing. Priming with a conserved subregion, such as FP, can thus induce Abs with binding-energy hotspots coincident with the target subregion and capable of broad neutralization.

Cryo-EM Structures and Regulation of Arabinofuranosyltransferase AftD from Mycobacteria.

Mycobacterium tuberculosis causes tuberculosis, a disease that kills over 1 million people each year. Its cell envelope is a common antibiotic target and has a unique structure due, in part, to two lipidated polysaccharides-arabinogalactan and lipoarabinomannan. Arabinofuranosyltransferase D (AftD) is an essential enzyme involved in assembling these glycolipids. We present the 2.9-Å resolution structure of M. abscessus AftD, determined by single-particle cryo-electron microscopy. AftD has a conserved GT-C glycosyltransferase fold and three carbohydrate-binding modules. Glycan array analysis shows that AftD binds complex arabinose glycans. Additionally, AftD is non-covalently complexed with an acyl carrier protein (ACP). 3.4- and 3.5-Å structures of a mutant with impaired ACP binding reveal a conformational change, suggesting that ACP may regulate AftD function. Mutagenesis experiments using a conditional knockout constructed in M. smegmatis confirm the essentiality of the putative active site and the ACP binding for AftD function.

B56δ long-disordered arms form a dynamic PP2A regulation interface coupled with global allostery and Jordan's syndrome mutations.

Intrinsically disordered regions (IDR) and short linear motifs (SLiMs) play pivotal roles in the intricate signaling networks governed by phosphatases and kinases. B56δ (encoded by PPP2R5D) is a regulatory subunit of protein phosphatase 2A (PP2A) with long IDRs that harbor a substrate-mimicking SLiM and multiple phosphorylation sites. De novo missense mutations in PPP2R5D cause intellectual disabilities (ID), macrocephaly, Parkinsonism, and a broad range of neurological symptoms. Our single-particle cryo-EM structures of the PP2A-B56δ holoenzyme reveal that the long, disordered arms at the B56δ termini fold against each other and the holoenzyme core. This architecture suppresses both the phosphatase active site and the substrate-binding protein groove, thereby stabilizing the enzyme in a closed latent form with dual autoinhibition. The resulting interface spans over 190 Šand harbors unfavorable contacts, activation phosphorylation sites, and nearly all residues with ID-associated mutations. Our studies suggest that this dynamic interface is coupled to an allosteric network responsive to phosphorylation and altered globally by mutations. Furthermore, we found that ID mutations increase the holoenzyme activity and perturb the phosphorylation rates, and the severe variants significantly increase the mitotic duration and error rates compared to the normal variant.

FACT caught in the act of manipulating the nucleosome.

The organization of genomic DNA into nucleosomes profoundly affects all DNA-related processes in eukaryotes. The histone chaperone known as 'facilitates chromatin transcription' (FACT1) (consisting of subunits SPT16 and SSRP1) promotes both disassembly and reassembly of nucleosomes during gene transcription, DNA replication and DNA repair2. However, the mechanism by which FACT causes these opposing outcomes is unknown. Here we report two cryo-electron-microscopic structures of human FACT in complex with partially assembled subnucleosomes, with supporting biochemical and hydrogen-deuterium exchange data. We find that FACT is engaged in extensive interactions with nucleosomal DNA and all histone variants. The large DNA-binding surface on FACT appears to be protected by the carboxy-terminal domains of both of its subunits, and this inhibition is released by interaction with H2A-H2B, allowing FACT-H2A-H2B to dock onto a complex containing DNA and histones H3 and H4 (ref. 3). SPT16 binds nucleosomal DNA and tethers H2A-H2B through its carboxy-terminal domain by acting as a placeholder for DNA. SSRP1 also contributes to DNA binding, and can assume two conformations, depending on whether a second H2A-H2B dimer is present. Our data suggest a compelling mechanism for how FACT maintains chromatin integrity during polymerase passage, by facilitating removal of the H2A-H2B dimer, stabilizing intermediate subnucleosomal states and promoting nucleosome reassembly. Our findings reconcile discrepancies regarding the many roles of FACT and underscore the dynamic interactions between histone chaperones and nucleosomes.

Chemosensory protein regulates the behavioural response of Frankliniella intonsa and Frankliniella occidentalis to tomato zonate spot virus-Infected pepper (Capsicum annuum).

Many herbivorous insects rely on plant volatiles to locate their host plants. Vector-borne viral infections induce changes in plant volatiles, which render infected plants more attractive to insect vectors. However, the detailed mechanisms underlying the olfactory responses of insect vectors induced by the volatiles produced by virus-infected plants are poorly understood. Here, we show that volatiles emitted by pepper (Capsicum annuum) plants infected with tomato zonate spot virus (TZSV), particularly the volatile cis-3-hexenal, which is recognized by chemosensory protein 1 of the thrips Frankliniella intonsa (FintCSP1), are more attractive to F. intonsa than the volatiles emitted by non-infected pepper plants. FintCSP1 is highly abundant in the antenna of F. intonsa. Silencing of FintCSP1 significantly decreased electroantennogram responses of F. intonsa antennae to cis-3-hexenal and impaired thrips' responses to TZSV-infected pepper plants and cis-3-hexenal, as assessed using a Y-tube olfactometer. Three-dimensional model predictions indicated that FintCSP1 consists of seven α-helixes and two disulfide bridges. Molecular docking analysis suggested that cis-3-hexenal is positioned deep inside the binding pocket of FintCSP1 and binds to residues of the protein. We combined site-directed mutagenesis and fluorescence binding assays and identified three hydrophilic residues, Lys26, Thr28, and Glu67, of FintCSP1 as being critical for cis-3-hexenal binding. Furthermore, CSP of F. occidentalis (FoccCSP) is also a key olfactory protein involved in modulating the behaviour of F. occidentalis to TZSV-infected pepper. This study revealed the specific binding characteristics of CSPs to cis-3-hexenal and confirmed the general hypothesis that virus infections induce changes in host volatiles, which can be recognized by the olfactory proteins of the insect vector to enhance vector attraction and this may facilitate viral spread and transmission.

Induced Aggregation, Solvent Regulation, and Supracluster Assembly of Aluminum Oxo Clusters.

ConspectusRecent years have witnessed the development of cluster materials as they are atomically precise molecules with uniform size and solution-processability, which are unattainable with traditional nanoparticles or framework materials. The motivation for studying Al(III) chemistry is not only to understand the aggregation process of aluminum in the environment but also to develop novel low-cost materials given its natural abundance. However, the Al-related clusters are underdeveloped compared to the coinage metals, lanthanides, and transition metals. The challenge in isolating crystalline compounds is the lack of an effective method to realize the controllable hydrolysis of Al(III) ions. Compared with the traditional hydrolysis of inorganic Al(III) salts in highly alkaline solutions and hydrolysis of aluminum trialkyl compounds conducted carefully in an inert operating environment, we herein developed an effective way to control the hydrolysis of aluminum isopropanol through an alcoxalation reaction. By solvothermal/low melting point solid melting synthesis and using "ligand aggregation, solvent regulation, and supracluster assembly" strategies, our laboratory has established an organic-inorganic hybrid system of aluminum oxo clusters (AlOCs). The employment of organic ligands promotes the aggregation and slows the hydrolysis of Al(III) ions, which in turn improves the crystallization process. The regulation of the structure types can be achieved through the selection of ligands and the supporting solvents. Compared with the traditional condensed polyoxoaluminates, we successfully isolated a broad range of porous AlOCs, including aluminum molecular rings and Archimedes aluminum oxo cages. By studying ring expansion, structural transformation, and intermolecular supramolecular assembly, we demonstrate unique and unprecedented structural controllability and assembly behavior in cluster science. The advancement of this universal synthetic method is to realize materials customization through modularly oriented supracluster assembly. In this Account, we will provide a clear-cut definition and terminology of "ligand aggregation, solvent regulation, and supracluster assembly". Then we will discuss the discovery in this area by using a strategy, such as aluminum molecular ring, ring size expansion, ring supracluster assembly, etc. Furthermore, given the internal and external pore structures, as well as the solubility and modifiability of the AlOCs, we will demonstrate their potential applications in both the solid and liquid phases, such as iodine capture, the optical limiting responses, and dopant in polymer dielectrics. The strategy herein can be applied to extensive cluster science and promote the research of main group element chemistry. The new synthetic method, fascinating clusters, and unprecedented assembly behaviors we have discovered will advance Al(III) chemistry and will also lay the foundation for functional applications.

Elevated BICD2 DNA methylation in blood of major depressive disorder patients and reduction of depressive-like behaviors in hippocampal Bicd2-knockdown mice.

Major depressive disorder (MDD) is a prevalent and devastating mental illness. To date, the diagnosis of MDD is largely dependent on clinical interviews and questionnaires and still lacks a reliable biomarker. DNA methylation has a stable and reversible nature and is likely associated with the course and therapeutic efficacy of complex diseases, which may play an important role in the etiology of a disease. Here, we identified and validated a DNA methylation biomarker for MDD from four independent cohorts of the Chinese Han population. First, we integrated the analysis of the DNA methylation microarray (n = 80) and RNA expression microarray data (n = 40) and identified BICD2 as the top-ranked gene. In the replication phase, we employed the Sequenom MassARRAY method to confirm the DNA hypermethylation change in a large sample size (n = 1,346) and used the methylation-sensitive restriction enzymes and a quantitative PCR approach (MSE-qPCR) and qPCR method to confirm the correlation between DNA hypermethylation and mRNA down-regulation of BICD2 (n = 60). The results were replicated in the peripheral blood of mice with depressive-like behaviors, while in the hippocampus of mice, Bicd2 showed DNA hypomethylation and mRNA/protein up-regulation. Hippocampal Bicd2 knockdown demonstrates antidepressant action in the chronic unpredictable mild stress (CUMS) mouse model of depression, which may be mediated by increased BDNF expression. Our study identified a potential DNA methylation biomarker and investigated its functional implications, which could be exploited to improve the diagnosis and treatment of MDD.

Nanozyme-Enhanced Probiotic Spores Regulate the Intestinal Microenvironment for Targeted Acute Gastroenteritis Therapy.

Antibiotic therapeutics to combat intestinal pathogen infections often exacerbate microbiota dysbiosis and impair mucosal barrier functions. Probiotics are promising strategies, because they inhibit pathogen colonization and improve intestinal microbiota imbalance. Nevertheless, their limited targeting ability and susceptibility to oxidative stress have hindered their therapeutic potential. To tackle these challenges, Ces3 is synthesized by in situ growth of CeO2 nanozymes with positive charges on probiotic spores, facilitating electrostatic interactions with negatively charged pathogens and possessing a high reactive oxygen species (ROS) scavenging activity. Importantly, Ces3 can resist the harsh environment of the gastrointestinal tract. In mice with S. Typhimurium-infected acute gastroenteritis, Ces3 shows potent anti-S. Typhimurium activity, thereby alleviating the dissemination of S. Typhimurium into other organs. Additionally, owing to its O2 deprivation capacity, Ces3 promotes the proliferation of anaerobic probiotics, reshaping a healthy intestinal microbiota. This work demonstrates the promise of combining antibacterial, anti-inflammatory, and O2 content regulation properties for acute gastroenteritis therapy.

Assembly of Homochiral Aluminum Oxo Clusters for Circularly Polarized Luminescence.

Chiral aluminum oxo clusters (cAlOCs) are distinguished from other classes of materials on account of their abundance in the earth's crust and their potential for sustainable development. However, the practical synthesis of cAlOCs is rarely known. Herein, we adopt a synergistic coordination strategy by using chiral amino acid ligands as bridges and auxiliary pyridine-2,6-dicarboxylic acid as chelating ligands and successfully isolate an extensive family of cAlOCs. They integrate molecular chirality, absolute helicity, and intrinsic hydrogen-bonded chiral topology. Moreover, they have the structural characteristics of one-dimensional channels and replaceable counteranions, which make them well combined with fluorescent dyes for circularly polarized luminescence (CPL). The absolute luminescence dissymmetry factor (glum) of up to the 10-3 order is comparable to several noble metals, revealing the enormous potential of cAlOCs in low-cost chiral materials. We hope this work will inspire new discoveries in the field of chirality and provide new opportunities for constructing low-cost chiral materials.

Homocysteine-potentiated Kelch-like ECH-associated protein 1 promotes senescence of neuroblastoma 2a cells via inhibiting ubiquitination of ß-catenin.

Elevated serum homocysteine (Hcy) level is a risk factor for Alzheimer's disease (AD) and accelerates cell aging. However, the mechanism by which Hcy induces neuronal senescence remains largely unknown. In this study, we observed that Hcy significantly promoted senescence in neuroblastoma 2a (N2a) cells with elevated ß-catenin and Kelch-like ECH-associated protein 1 (KEAP1) levels. Intriguingly, Hcy promoted the interaction between KEAP1 and the Wilms tumor gene on the X chromosome (WTX) while hampering the ß-catenin-WTX interaction. Mechanistically, Hcy attenuated the methylation level of the KEAP1 promoter CpG island and activated KEAP1 transcription. However, a slow degradation rate rather than transcriptional activation contributed to the high level of ß-catenin. Hcy-upregulated KEAP1 competed with ß-catenin to bind to WTX. Knockdown of both ß-catenin and KEAP1 attenuated Hcy-induced senescence in N2a cells. Our data highlight a crucial role of the KEAP1-ß-catenin pathway in Hcy-induced neuronal-like senescence and uncover a promising target for AD treatment.

Comprehensive analysis of annexin gene family and its expression in response to branching architecture and salt stress in crape myrtle.

BACKGROUND: Annexin (ANN) is calcium (Ca2+)-dependent and phospholipid binding protein family, which is involved in plant growth and development and response to various stresses. However, little known about ANN genes were identified from crape myrtle, an ornamental horticultural plant widely cultivated in the world. RESULTS: Here, 9 LiANN genes were identified from Lagerstroemia indica, and their characterizations and functions were investigated in L. indica for the first time. The LiANN genes were divided into 2 subfamilies. The gene structure, chromosomal location, and collinearity relationship were also explored. In addition, the GO annotation analysis of these LiANNs indicated that they are enriched in molecular functions, cellular components, and biological processes. Moreover, transcription factors (TFs) prediction analysis revealed that bHLH, MYB, NAC, and other TFs can interact with the LiANN promoters. Interestingly, the LiANN2/4/6-9 were demonstrated to play critical roles in the branching architecture of crape myrtle. Furthermore, the LiANN2/6/8/9 were differentially expressed under salt treatment, and a series of TFs regulating LiANN2/6/8/9 expression were predicted to play essential roles in salt resistance. CONCLUSIONS: These results shed light on profile and function of the LiANN gene family, and lay a foundation for further studies of the LiANN genes.

Genomic and transcriptomic studies on flavonoid biosynthesis in Lagerstroemia indica.

BACKGROUND: Lagerstroemia indica is a widely cultivated ornamental woody shrub/tree of the family Lythraceae that is used as a traditional medicinal plant in East Asia and Egypt. However, unlike other ornamental woody plants, its genome is not well-investigated, which hindered the discovery of the key genes that regulate important traits and the synthesis of bioactive compounds. RESULTS: In this study, the genomic sequences of L. indica were determined using several next-generation sequencing technologies. Altogether, 324.01 Mb sequences were assembled and 98.21% (318.21 Mb) of them were placed in 24 pseudo-chromosomes. The heterozygosity, repeated sequences, and GC residues occupied 1.65%, 29.17%, and 38.64% of the genome, respectively. In addition, 28,811 protein-coding gene models, 327 miRNAs, 552 tRNAs, 214 rRNAs, and 607 snRNAs were identified. The intra- and interspecies synteny and Ks analysis revealed that L. indica exhibits a hexaploidy. The co-expression profiles of the genes involved in the phenylpropanoid (PA) and flavonoid/anthocyanin (ABGs) pathways with the R2R3 MYB genes (137 members) showed that ten R2R3 MYB genes positively regulate flavonoid/anthocyanin biosynthesis. The colors of flowers with white, purple (PB), and deep purplish pink (DPB) petals were found to be determined by the levels of delphinidin-based (Dp) derivatives. However, the substrate specificities of LiDFR and LiOMT probably resulted in the different compositions of flavonoid/anthocyanin. In L. indica, two LiTTG1s (LiTTG1-1 and LiTTG1-2) were found to be the homologs of AtTTG1 (WD40). LiTTG1-1 was found to repress anthocyanin biosynthesis using the tobacco transient transfection assay. CONCLUSIONS: This study showed that the ancestor L. indica experienced genome triplication approximately 38.5 million years ago and that LiTTG1-1 represses anthocyanin biosynthesis. Furthermore, several genes such as LiDFR, LiOMTs, and R2R3 LiMYBs are related to anthocyanin biosynthesis. Further studies are required to clarify the mechanisms and alleles responsible for flower color development.

A Self-Cascade Oxygen-Generating Nanomedicine for Multimodal Tumor Therapy.

Natural and artificial enzyme oxygen-generating systems for photodynamic therapy (PDT) are developed for tumor treatment, yet they have fallen short of the desired efficacy. Moreover, both the enzymes and photosensitizers usually need carriers for efficient delivery to tumor sites. Here, a self-cascade-enhanced multimodal tumor therapy is developed by ingeniously integrating self-cascade-enhanced PDT with Zn2+-overloading therapy. Manganese-porphyrin (TCPP-Mn) is chosen both as the photosensitizer and catalase (CAT) mimic, which can be encapsulated within glucose oxidase (GOx). Acid-responsive zeolitic imidazolate framework-8 (ZIF-8) is applied as the carrier for TCPP-Mn@GOx (T@G), attaining TCPP-Mn@GOx@ZIF-8 (T@G@Z). T@G@Z demonstrates robust anti-tumor ability as follows: upon the structural degradation of ZIF-8, GOx can mediate the oxidation of glucose and generate hydrogen peroxide (H2O2); TCPP-Mn can catalyze H2O2 into O2 for self-cascade-enhanced PDT; meanwhile, the released Zn2+ can enhance oxidative stress and induce mitochondrial dysfunction by destroying mitochondrial membrane potential; furthermore, immunotherapy can be activated to resist primary tumor and tumor metastasis. The self-cascade-enhanced T@G@Z exhibited its potential application for further tumor management.

Designing External Pores of Aluminum Oxo Polyhedrons for Efficient Iodine Capture.

Although metal-organic polyhedra (MOPs) expansion has been studied to date, it is still a rare occurrence for their porous intermolecular assembly for iodine capture. The major limitation is the lack of programmable and controllable methods for effectively constructing and utilizing the exterior cavities. Herein, the goal of programmable porous intermolecular assembly is realized in the first family of aluminum oxo polyhedrons (AlOPs) using ligands with directional H-bonding donor/acceptor pairs and auxiliary alcohols as structural regulation sites. The approach has the advantage of avoiding the use of expensive edge-directed ditopic and face-directed tritopic ligands in the general synthesis strategy of MOPs. Combining theoretical calculations and experiments, the intrinsic relationship is revealed between alcohol ligands and the growth mechanism of AlOPs. The maximum I2 uptake based on the mass gain during sorption corresponds to 2.35 g g-1, representing the highest reported I2 sorption by an MOP. In addition, it can be easily regenerated and maintained the iodine sorption capacity, revealing its further potential application. This method of constructing stable and programmable porous materials will provide a new way to solve problems such as radionuclide capture.

Carbon footprint of synthetic nitrogen under staple crops: A first cradle-to-grave analysis.

More than half of the world's population is nourished by crops fertilized with synthetic nitrogen (N) fertilizers. However, N fertilization is a major source of anthropogenic emissions, augmenting the carbon footprint (CF). To date, no global quantification of the CF induced by N fertilization of the main grain crops has been performed, and quantifications at the national scale have neglected the CO2 assimilated by plants. A first cradle-to-grave life cycle assessment was performed to quantify the CF of the N fertilizers' production, transportation, and application to the field and the uses of the produced biomass in livestock feed and human food, as well as biofuel production. We quantified the direct and indirect inventories emitted or sequestered by N fertilization of main grain crops: wheat, maize, and rice. Grain food produced with N fertilization had a net CF of 7.4 Gt CO2eq. in 2019 after excluding the assimilated C in plant biomass, which accounted for a quarter of the total CF. The cradle (fertilizer production and transportation), gate (fertilizer application, and soil and plant systems), and grave (feed, food, biofuel, and losses) stages contributed to the CF by 2%, 11%, and 87%, respectively. Although Asia was the top grain producer, North America contributed 38% of the CF due to the greatest CF of the grave stage (2.5 Gt CO2eq.). The CF of grain crops will increase to 21.2 Gt CO2eq. in 2100, driven by the rise in N fertilization to meet the growing food demand without actions to stop the decline in N use efficiency. To meet the targets of climate change, we introduced an ambitious mitigation strategy, including the improvement of N agronomic efficiency (6% average target for the three crops) and manufacturing technology, reducing food losses, and global conversion to healthy diets, whereby the CF can be reduced to 5.6 Gt CO2eq. in 2100.

Methionine redox regulation of actin-interacting proteins primarily governs antioxidative signaling and response to the salvianolic acid B treatment in EA.hy926 cells.

Actin-interacting proteins are important molecules for filament assembly and cytoskeletal signaling within vascular endothelium. Disruption in their interactions causes endothelial pathogenesis through redox imbalance. Actin filament redox regulation remains largely unexplored, in the context of pharmacological treatment. This work focused on the peptidyl methionine (M) redox regulation of actin-interacting proteins, aiming at elucidating its role on governing antioxidative signaling and response. Endothelial EA.hy926 cells were subjected to treatment with salvianolic acid B (Sal B) and tert-butyl-hydroperoxide (tBHP) stimulation. Mass spectrometry was employed to characterize redox status of proteins, including actin, myosin-9, kelch-like erythroid-derived cap-n-collar homology-associated protein 1 (Keap1), plastin-3, prelamin-A/C and vimentin. The protein redox landscape revealed distinct stoichiometric ratios or reaction site transitions mediated by M sulfoxide reductase and reactive oxygen species. In comparison with effects of tBHP stimulation, Sal B treatment prevented oxidation at actin M325, myosin-9 M1489/1565, Keap1 M120, plastin-3 M592, prelamin-A/C M187/371/540 and vimentin M344. For Keap1, reaction site was transitioned within its scaffolding region to the actin ring. These protein M oxidation regulations contributed to the Sal B cytoprotective effects on actin filament. Additionally, regarding the Keap1 homo-dimerization region, Sal B preventive roles against M120 oxidation acted as a primary signal driver to activate nuclear factor erythroid 2-related factor 2 (Nrf2). Transcriptional splicing of non-POU domain-containing octamer-binding protein was validated during the Sal B-mediated overexpression of NAD(P)H dehydrogenase [quinone] 1. This molecular redox regulation of actin-interacting proteins provided valuable insights into the phenolic structures of Sal B analogs, showing potential antioxidative effects on vascular endothelium.

Pediatric-inspired regimen for adolescent and adult patients with Philadelphia chromosome-negative acute lymphoblastic leukemia: a prospective study from China.

Several international centers have used and reported pediatric-inspired regimens for adolescent and adult patients with Philadelphia chromosome-negative acute lymphoblastic leukemia (Ph- ALL). However, there is a lack of prospective data on the Chinese population. Herein, we performed a prospective study with a pediatric-inspired regimen (IH-2014 regimen) in treating adolescent and adult Ph- ALL patients in our center. From 2014 to 2021, a total of 415 patients aged between 14 and 65 years (median age, 27) were included in this study. After a median follow-up of 40.8 months, the 5-year overall survival, disease-free survival, and event-free survival rates were 53.8%, 51.1% and 45.0%, respectively. The regimen was generally well tolerated and safe, and the overall chemotherapy-related mortality was 3.6%. Age ≥ 40 years and persistent detectable minimal residual disease (MRD) post-induction were independent prognostic factors. Traditional risk factors for adult patients combined with MRD post-induction exhibit predictive significance for survival and relapse, which is helpful in the selection of subsequent treatment. Patients with high risk factors who can achieve deep MRD response after induction do not derive benefit from allogeneic hematopoietic stem cell transplantation.

Comparative genomic analysis reveals expansion of the DnaJ gene family in Lagerstroemia indica and its members response to salt stress.

DnaJs/Hsp40s/JPDs are obligate co-chaperones of heat shock proteins (Hsp70), performing crucial biological functions within organisms. A comparative genome analysis of four genomes (Vitis vinifera, Eucalyptus grandis, Lagerstroemia indica, and Punica granatum) revealed that the DnaJ gene family in L. indica has undergone expansion, although not to the extent observed in P. granatum. Inter-genome collinearity analysis of four plants indicates that members belonging to Class A and B are more conserved during evolution. In L. indica, the expanded members primarily belong to Class-C. Tissue expression patterns and the biochemical characterization of LiDnaJs further suggested that DnaJs may be involved in numerous biological processes in L. indica. Transcriptome and qPCR analyses of salt stressed leaves identified at least ten LiDnaJs that responded to salt stress. In summary, we have elucidated the expansion mechanism of the LiDnaJs, which is attributed to a recent whole-genome triplication. This research laid the foundation for functional analysis of LiDnaJs and provides gene resources for breeding salt-tolerant varieties of L. indica.

Streamlining heterologous expression of top carbonic anhydrases in Escherichia coli: bioinformatic and experimental approaches.

BACKGROUND: Carbonic anhydrase (CA) enzymes facilitate the reversible hydration of CO2 to bicarbonate ions and protons. Identifying efficient and robust CAs and expressing them in model host cells, such as Escherichia coli, enables more efficient engineering of these enzymes for industrial CO2 capture. However, expression of CAs in E. coli is challenging due to the possible formation of insoluble protein aggregates, or inclusion bodies. This makes the production of soluble and active CA protein a prerequisite for downstream applications. RESULTS: In this study, we streamlined the process of CA expression by selecting seven top CA candidates and used two bioinformatic tools to predict their solubility for expression in E. coli. The prediction results place these enzymes in two categories: low and high solubility. Our expression of high solubility score CAs (namely CA5-SspCA, CA6-SazCAtrunc, CA7-PabCA and CA8-PhoCA) led to significantly higher protein yields (5 to 75 mg purified protein per liter) in flask cultures, indicating a strong correlation between the solubility prediction score and protein expression yields. Furthermore, phylogenetic tree analysis demonstrated CA class-specific clustering patterns for protein solubility and production yields. Unexpectedly, we also found that the unique N-terminal, 11-amino acid segment found after the signal sequence (not present in its homologs), was essential for CA6-SazCA activity. CONCLUSIONS: Overall, this work demonstrated that protein solubility prediction, phylogenetic tree analysis, and experimental validation are potent tools for identifying top CA candidates and then producing soluble, active forms of these enzymes in E. coli. The comprehensive approaches we report here should be extendable to the expression of other heterogeneous proteins in E. coli.

Examination of the Rate and Extent of Drug Released from Commercial Topical Delivery Systems During Wear: An Example with Lidocaine Topical Systems.

OBJECTIVE: This study aimed to determine the extent and rate of lidocaine released in vivo from two bioequivalent topical delivery systems (TDS) by using complementary assessments: pharmacokinetic analysis in healthy human volunteers, and residual lidocaine in TDS following 12 h of wear. The goal was to explore a potentially more clinically meaningful strength presentation than percent active pharmaceutical ingredient loaded in topical systems. METHODS: A three-arm, open-label, crossover clinical study was conducted in 23 human subjects, with 5% lidocaine topical systems from two manufacturers, and intravenous lidocaine administration. Residual drug and LC-MS/MS analyses were performed on worn TDS and serum samples. The rate and extent of drug released from the TDS during wear were determined through (1) calculations of consumed lidocaine via analysis of residual drug in worn TDS, and (2) a pharmacokinetic approach via derivation of the absolute clearance and serum lidocaine concentration at steady state. RESULTS: Overall the pharmacokinetic approach underestimated the amount transferred to the subject and exhibited greater variability, which may relate to natural inter-subject variability in pharmacokinetic parameters. Further, lidocaine TDS are intended for localized, not systemic, delivery and this may also explain some of the variability seen in the systemic serum concentrations. CONCLUSIONS: The residual drug and pharmacokinetic approaches align well for transdermal formulations, but the differences in administration route (topical versus transdermal) all but eliminates the potential use of the pharmacokinetic approach unless additional compartmental modeling is explored.