Characterization of Firmiana danxiaensis plastomes and comparative analysis of Firmiana: insight into its phylogeny and evolution.

BACKGROUND: Firmiana danxiaensis is a critically endangered and ecologically important tree currently only found in four locations in Danxia or Karst habitats in northern Guangdong Province, China. The specialized habitat preference makes it an ideal model species for study of adaptive evolution. Meanwhile, the phylogenetic relationships of F. danxiaensis in four locations under two landforms are unclear. Therefore, we sequenced its complete chloroplast (cp.) genomes and conducted comprehensive interspecific and intrageneric plastome studies. RESULTS: The F. danxiaensis plastomes in four locations showed a typical quadripartite and circular structure that ranged from 160,832 to 161,206 bp in size, with 112 unique genes encoded. Comparative genomics showed that the plastomes of F. danxiaensis were relatively conserved with high similarity of genome organization, gene number, GC content and SSRs. While the genomes revealed higher biased codon preferences in Karst habitat than those in Danxia habitats. Eighteen and 11 divergent hotpots were identified at interspecific and intrageneric levels for species identification and further phylogenetic studies. Seven genes (clpP, accD, ccsA, ndhH, rpl20, rpoC2, and rps4) were under positive selection and may be related to adaptation. Phylogenetic analysis revealed that F. danxiaensis is sister to F. major and F. simplex. However, the interspecific relationships are not consistent with the habitat types. CONCLUSIONS: The characteristics and interspecific relationship of F. danxiaensis plastomes provide new insights into further integration of geographical factors, environmental factors, and genetic variations on the genomic study of F. danxiaensis. Together, our study will contribute to the study of species identification, population genetics, and conservation biology of F. danxiaensis.

Giving birth after fertility-sparing treatment for primary leiomyosarcoma of the fallopian tube.

Primary leiomyosarcoma of the fallopian tube (PLFT) is an extremely rare gynecological malignancy that has only been described in case reports. Fertility-sparing treatment for PLFT has not been reported previously. A 24-year-old nulligravida woman was diagnosed with stage IC1 PLFT in the right fallopian tube after experiencing right lower quadrant pain for 2 weeks. She underwent laparoscopic right salpingectomy to preserve fertility followed by adjuvant chemotherapy with gemcitabine/docetaxel. She subsequently became pregnant spontaneously, delivering a term baby 27 months after treatment. This appears to be the only report of the use of fertility-preserving treatment for PLFT. The success of the treatment provides valuable information on the preservation of fertility in young women with PLFT.

Radiological assessment of immunotherapy effects and immune checkpoint-related pneumonitis for lung cancer.

Immune checkpoint inhibitors (ICIs) therapy have revolutionized advanced lung cancer care. Interestingly, the host responses for patients received ICIs therapy are distinguishing from those with cytotoxic drugs, showing potential initial transient worsening of disease burden, pseudoprogression and delayed time to treatment response. Thus, a new imaging criterion to evaluate the response for immunotherapy should be developed. ICIs treatment is associated with unique adverse events, including potential life-threatening immune checkpoint inhibitor-related pneumonitis (ICI-pneumonitis) if treated patients are not managed promptly. Currently, the diagnosis and clinical management of ICI-pneumonitis remain challenging. As the clinical manifestation is often nonspecific, computed tomography (CT) scan and X-ray films play important roles in diagnosis and triage. This article reviews the complications of immunotherapy in lung cancer and illustrates various radiologic patterns of ICI-pneumonitis. Additionally, it is tried to differentiate ICI-pneumonitis from other pulmonary pathologies common to lung cancer such as radiation pneumonitis, bacterial pneumonia and coronavirus disease of 2019 (COVID-19) infection in recent months. Maybe it is challenging to distinguish radiologically but clinical presentation may help.

M6A2Target: a comprehensive database for targets of m6A writers, erasers and readers.

N6-methyladenosine (m6A) is the most abundant posttranscriptional modification in mammalian mRNA molecules and has a crucial function in the regulation of many fundamental biological processes. The m6A modification is a dynamic and reversible process regulated by a series of writers, erasers and readers (WERs). Different WERs might have different functions, and even the same WER might function differently in different conditions, which are mostly due to different downstream genes being targeted by the WERs. Therefore, identification of the targets of WERs is particularly important for elucidating this dynamic modification. However, there is still no public repository to host the known targets of WERs. Therefore, we developed the m6A WER target gene database (m6A2Target) to provide a comprehensive resource of the targets of m6A WERs. M6A2Target provides a user-friendly interface to present WER targets in two different modules: 'Validated Targets', referred to as WER targets identified from low-throughput studies, and 'Potential Targets', including WER targets analyzed from high-throughput studies. Compared to other existing m6A-associated databases, m6A2Target is the first specific resource for m6A WER target genes. M6A2Target is freely accessible at http://m6a2target.canceromics.org.

Engineering Rhodosporidium toruloides for production of 3-hydroxypropionic acid from lignocellulosic hydrolysate.

Microbial production of valuable bioproducts is a promising route towards green and sustainable manufacturing. The oleaginous yeast, Rhodosporidium toruloides, has emerged as an attractive host for the production of biofuels and bioproducts from lignocellulosic hydrolysates. 3-hydroxypropionic acid (3HP) is an attractive platform molecule that can be used to produce a wide range of commodity chemicals. This study focuses on establishing and optimizing the production of 3HP in R. toruloides. As R. toruloides naturally has a high metabolic flux towards malonyl-CoA, we exploited this pathway to produce 3HP. Upon finding the yeast capable of catabolizing 3HP, we then implemented functional genomics and metabolomic analysis to identify the catabolic pathways. Deletion of a putative malonate semialdehyde dehydrogenase gene encoding an oxidative 3HP pathway was found to significantly reduce 3HP degradation. We further explored monocarboxylate transporters to promote 3HP transport and identified a novel 3HP transporter in Aspergillus pseudoterreus by RNA-seq and proteomics. Combining these engineering efforts with media optimization in a fed-batch fermentation resulted in 45.4 g/L 3HP production. This represents one of the highest 3HP titers reported in yeast from lignocellulosic feedstocks. This work establishes R. toruloides as a host for 3HP production from lignocellulosic hydrolysate at high titers, and paves the way for further strain and process optimization towards enabling industrial production of 3HP in the future.

Identification of a specific exporter that enables high production of aconitic acid in Aspergillus pseudoterreus.

Aconitic acid is an unsaturated tricarboxylic acid that is attractive for its potential use in manufacturing biodegradable and biocompatible polymers, plasticizers, and surfactants. Previously Aspergillus pseudoterreus was engineered as a platform to produce aconitic acid by deleting the cadA (cis-aconitic acid decarboxylase) gene in the itaconic acid biosynthetic pathway. In this study, the aconitic acid transporter gene (aexA) was identified using comparative global discovery proteomics analysis between the wild-type and cadA deletion strains. The protein AexA belongs to the Major Facilitator Superfamily (MFS). Deletion of aexA almost abolished aconitic acid secretion, while its overexpression led to a significant increase in aconitic acid production. Transportation of aconitic acid across the plasma membrane is a key limiting step in its production. In vitro, proteoliposome transport assay further validated AexA's function and substrate specificity. This research provides new approaches to efficiently pinpoint and characterize exporters of fungal organic acids and accelerate metabolic engineering to improve secretion capability and lower the cost of bioproduction.

Highly expressed RPLP2 inhibits ferroptosis to promote hepatocellular carcinoma progression and predicts poor prognosis.

BACKGROUND: RPLP2, an integral part of ribosomal stalk, plays an important role in the tumorigenesis of various cancers. However, its specific effect on HCC remains elusive. METHODS: TCGA, GTEx, HCCDB, HPA, UALCAN, MethSurv, TISIDB, K-M plotter, FerrDb, RNAactDrug, STRING, Cytoscape and R studio were conducted for bioinformatics analysis. RPLP2 expression level in HCC was verified by IHC and western blot. IHC was used to demonstrate the immune cell infiltration. Functional experiments including CCK8, transwell and colony formation assays, and nude mice xenograft model were performed for in vitro and in vivo validation. Western blot, IHC, CCK8 assay and detection of GSH and lipid ROS were adopted to determine the effect of RPLP2 on the ferroptosis of HCC cells. RESULTS: Here, we demonstrate that elevated level of RPLP2 is strongly associated with advanced clinicopathologic features, and predicts poor prognosis of HCC patients. Additionally, DNA methylation level of RPLP2 decreases in HCC, and significantly correlates with patients outcome. Moreover, high RPLP2 expression level is linked closely to the unfavorable immune infiltration. Most importantly, RPLP2 positively associates with ferroptosis suppressor GPX4, and inhibition of RPLP2 could lead to the acceleration of ferroptosis to suppress tumor progression of HCC. Last, drug sensitivity analysis predicts many drugs that potentially target RPLP2. CONCLUSION: Together, our study reveals previous unrecognized role of RPLP2 in HCC, and provides new regulatory mechanism of ferroptosis, indicating RPLP2 may be a novel therapeutic target for HCC.

ATXN2-mediated translation of TNFR1 promotes esophageal squamous cell carcinoma via m6A-dependent manner.

N6-methyladenosine (m6A) is the most prevalent RNA modification, and the effect of its dysregulation on esophageal squamous cell carcinoma (ESCC) development remains unclear. Here, by performing transcriptome-wide m6A sequencing in 16 ESCC tissue samples, we identified the key roles of m6A in TNFRSF1A (also known as TNFR1)-mediated MAPK and NF-κB activation in ESCC. Mechanistically, a functional protein involved in m6A methylation, ATXN2, is identified that augments the translation of TNFRSF1A by binding to m6A-modified TNFRSF1A mRNA. Upregulation of the TNFRSF1A protein level, a vital upstream switch for TNFRSF1A-mediated signaling events, activates the NF-κB and MAPK pathways and thus promotes ESCC development. Furthermore, TNFRSF1A m6A modifications and protein levels are upregulated in ESCC, and high levels of TNFRSF1A m6A and protein are correlated with poor ESCC patient survival. These results collectively indicate that the m6A-TNFRSF1A axis is critical for ESCC development and thus may serve as a potential druggable target.

18F-FDG PET/CT image of pericardial inflammatory myofibroblastic tumor.

Pericardial inflammatory myofibroblastic tumor (IMT) is very rare. Herein, we report fluorine-18-fluorodeoxyglucose (18F-FDG) positron emission tomography/computed tomography (PET/CT) findings of pericardial IMT in a 57-year-old woman. On conventional image, it presented as a pericardial mass with heterogeneous delay enhancement. On 18F-FDG PET/CT image, this lesion had mild 18F-FDG uptake with a maximum standardized uptake value (SUVmax) of 1.84. The postoperative pathology supported a diagnosis of IMT. Our case hints us that IMT should be regarded as a differential diagnosis when we meet a solitary pericardial mass with 18F-FDG uptake.

Iridium-Catalyzed Intramolecular ß-C-H Alkenylation of Ketones with Alkynes via a Hydride-Transfer Approach.

Direct functionalization of carbonyl ß C-H bonds without using directing groups has not been a trivial task, and it is even more challenging to realize the corresponding atom-economical transformations with common alkenes or alkynes as the coupling partner. Here, we describe the development of an iridium-catalyzed intramolecular direct ß-alkenylation of ketones with regular alkynes. The reaction is redox neutral, avoids strong acids or bases, and tolerates various functional groups. The combined experimental and computational mechanistic studies reveal a hydride-transfer pathway, involving ketone α,ß-desaturation, iridium-hydride-mediated alkyne insertion, conjugate addition, and α-protonation.

Remote Enantioselective [4 + 1] Annulation with Copper-Vinylvinylidene Intermediates.

The first copper-catalyzed enantioselective [4 + 1] annulation of yne-allylic esters with 1,3-dicarbonyl compounds was realized through an elegant remote stereocontrol strategy. The very remote ε regioselective nucleophilic substitution was developed by employing a novel chiral copper-vinylvinylidene species from the new C4 synthon yne-allylic esters. Thus, greatly diverse spirocycles were obtained with ample scope and excellent levels of chemo-, regio-, and enantioselectivities. Moreover, detailed mechanistic studies suggest an yne-allylic substitution and Conia-ene cascade pathway on the remote stereochemical induction progress.

Catalytic Asymmetric Vinylogous and Bisvinylogous Propargylic Substitution.

Distinct regio- and enantioselectivity control in copper-catalyzed vinylogous and bisvinylogous propargylic substitution has been accomplished by using a novel chiral N,N,P ligand. The developed method provides an efficient and selective approach to an array of highly enantioenriched alkynyl unsaturated carbonyl compounds. Salient features include excellent functional group tolerance and broad substrate scope. The synthetic utility of the developed method is further demonstrated by a gram-scale synthesis and by application to a range of transformations including enantioselective synthesis of unique challenging compounds.

Circular RNA circANKRD36 regulates Casz1 by targeting miR-599 to prevent osteoarthritis chondrocyte apoptosis and inflammation.

Osteoarthritis (OA) is an ageing-related disease characterized by articular cartilage degradation and joint inflammation. circRNA has been known to involve in the regulation of multiple inflammatory diseases including OA. However, the mechanism underlying how circRNA regulates OA remains to be elucidated. Here, we report circANKRD36 prevents OA chondrocyte apoptosis and inflammation by targeting miR-599, which specifically degrades Casz1. We performed circRNA sequencing in normal and OA tissues and found the expression of circANKRD36 is decreased in OA tissues. circANKRD36 is also reduced in IL-1ß-treated human chondrocytes. FACS analysis and Western blot showed that the knockdown of circANKRD36 promotes the apoptosis and inflammation of chondrocytes in IL-1ß stress. We then found miR-599 to be the target of circANKRD36 and correlate well with circANKRD36 both in vitro and in vivo. By database analysis and luciferase assay, Casz1 was found to be the direct target of miR-599. Casz1 helps to prevent apoptosis and inflammation of chondrocytes in response to IL-1ß. In conclusion, our results proved circANKRD36 sponge miR-599 to up-regulate the expression of Casz1 and thus prevent apoptosis and inflammation in OA.

Catalytic Synthesis of Atropisomeric o-Terphenyls with 1,2-Diaxes via Axial-to-Axial Diastereoinduction.

Herein, we report a modular and convergent strategy for the assembly of atropisomeric o-terphenyls with 1,2-diaxes via palladium/chiral norbornene cooperative catalysis and axial-to-axial diastereoinduction. Readily available aryl iodides, 2,6-substituted aryl bromides, and potassium aryl trifluoroborates are used as the building blocks, laying the foundation for diversity-oriented synthesis of these scaffolds (46 examples). Other features include the unique axial-to-axial diastereoinduction mode, construction of two axes in a single operation, and step economy. DFT calculations are performed to rationalize the axial-to-axial diastereoinduction process. Synthetic utilities of this method in preparation of atropisomeric oligophenyls, chiral catalysts, and ligands are demonstrated.

Clinical and genomic characterization of neutral tumor evolution in Head and Neck Squamous Cell Carcinoma.

Recent studies suggest that a significant proportion of cancers undergo neutral tumor evolution. We applied neutral evolution model in HNSCC patients from The Cancer Genome Atlas (TCGA). To ensure the accuracy of classification results, a sample with the purity of tumor <0.7 was excluded. A tumor sample was considered to evolve neutrally if R2 ≥ 0.98. We found that about 16% of HNSCC patients undergo neutral tumor evolution. We showed that neutral evolution HNSCC patients have better prognosis and higher activities of immune response pathways, and the numbers of co-occurring mutation events and significantly positive selection mutations are significantly less than non-neutral evolution HNSCC patients. In conclusion, we described a comprehensive clinical and genomic characteristics of neutral tumor evolution in Head and Neck Squamous Cell Carcinoma (HNSCC), and provided evidence that the evolution history of HNSCC has both clinical and biological implications.

Regio- and Enantioselective (3+3) Cycloaddition of Nitrones with 2-Indolylmethanols Enabled by Cooperative Organocatalysis.

The regio- and enantioselective (3+3) cycloaddition of nitrones with 2-indolylmethanols was accomplished by the cooperative catalysis of hexafluoroisopropanol (HFIP) and chiral phosphoric acid (CPA). Using this approach, a series of indole-fused six-membered heterocycles were synthesized in high yields (up to 98 %), with excellent enantioselectivities (up to 96 % ee) and exclusive regiospecificity. This approach enabled not only the first organocatalytic asymmetric (3+3) cycloaddition of nitrones but also the first C3-nucleophilic asymmetric (3+3) cycloaddition of 2-indolylmethanols. More importantly, theoretical calculations elucidated the role of the cocatalyst HFIP in helping CPA control the reactivity and enantioselectivity of the reaction, demonstrating a new mode of cooperative catalysis.

Atroposelective Access to Oxindole-Based Axially Chiral Styrenes via the Strategy of Catalytic Kinetic Resolution.

Atroposelective synthesis of axially chiral molecules has attracted substantial attention from chemists because of the importance of such molecules. However, catalytic asymmetric synthesis of axially chiral styrenes or vinyl arenes is underdeveloped and challenging due to the low rotational barrier and weak configurational stability of such molecules. Therefore, the development of powerful strategies for the catalytic atroposelective synthesis of axially chiral styrenes or vinyl arenes is of great importance. In this work, we have accomplished the first atroposelective access to oxindole-based axially chiral styrenes by the strategy of catalytic kinetic resolution, and this strategy offered two kinds of oxindole-based axially chiral styrene derivatives in good diastereoselectivities (up to 94:6 dr) and excellent enantioselectivities (up to 98% ee) with high selectivity factors (S up to 106). This strategy not only provides easy access to oxindole-based axially chiral styrenes but also offers a robust method for synthesizing bisamide derivatives bearing both axial and central chirality. More importantly, this strategy has added a new class of members to the atropisomeric family, especially to the family of axially chiral styrenes.

A fossil-calibrated phylogeny reveals the biogeographic history of the Cladrastis clade, an amphi-Pacific early-branching group in papilionoid legumes.

The early-branching Cladrastis clade of papilionoid legumes (Leguminosae, Papilionoideae) has an intriguing amphi-Pacific disjunct distribution in eastern Asia and temperate-tropical Americas. Here we used nuclear and three plastid regions to reconstruct the phylogenetic relationships and divergence times in the Cladrastis clade, as well as the evolution of morphological characters that might have been key in its biogeographic history. The ancestral character state estimation revealed that the most recent common ancestor of the Cladrastis clade was deciduous trees possessing compressed, winged fruits. The Cladrastis clade was inferred to have originated in the mid-latitude thermophilic forests of North America in the early Eocene, followed by the split between ancestors of wing-fruited Platyosprion and the non-wing-fruited group, and later the divergence of Cladrastis s.s. from the non-wing-fruited group in middle Eocene. Platyosprion and Cladrastis s.s. display an "out-of-North-America" biogeographic pattern and might have migrated to Asia via the Bering land bridge (BLB) or the North Atlantic land bridges (NALB) during middle to late Eocene. Our results, coupled with the relatively well documented fossil record for the clade, suggest that Platyosprion experienced an extinction event in North America caused by climatic cooling around the Eocene-Oligocene transition, which drove a major vegetation shift in western North America, in turn serving as a barrier for the vicariance of Pickeringia and Styphnolobium. The evolution of shrubby habit and sclerophyllous leaves in the former might be adaption to the chaparral vegetation in southwestern North America; the latter gained the trait of moniliform, succulent fruit. Styphnolobium further dispersed southward to tropical North America in the Oligocene, and eastward to Asia through BLB during middle Miocene. Subsequent sundering of BLB facilitated the vicariance of St. affine and St. japonicum.

Insights into 2-Indolylmethanol-Involved Cycloadditions: Origins of Regioselectivity and Enantioselectivity.

To gain insights into 2-indolylmethanol-involved reactions and to understand the origins of regioselectivity and enantioselectivity, theoretical investigations on the reaction mechanisms of three representative cycloadditions of 2-indolylmethanols have been carried out. In Ir-catalyzed regioselective (3 + 3) cycloaddition, it was found that the great difference between the energy barriers of the first initiating steps of the two pathways played a key role in determining the observed high regioselectivity and the C3-nucleophilicity of 2-indolylmethanol in this reaction. In chiral phosphoric acid (CPA)-catalyzed regioselective and enantioselective (3 + 3) and (3 + 4) cycloadditions, it was discovered that the great difference between the energy barriers of the transition states corresponding to the (R)- and (S)-configurations led to the observed high enantioselectivity of the products. In the presence of CPA, the C3-nucleophilicity of 2-indolylmethanol increased, resulting in exclusive regioselectivity. It was discovered that the electronic nature is not a decisive factor for the observed C3-regioselectivity in the delocalized cation of 2-indolylmethanol, and the steric factor should play a crucial role in the observed C3-regioselectivity. This study offers insights into the mechanisms of 2-indolylmethanol-involved reactions, which will give an in-depth understanding of the chemistry of 2-indolylmethanols and advance the development of this research field.

NEAT1/miR-193a-3p/SOX5 axis regulates cartilage matrix degradation in human osteoarthritis.

Long non-coding RNAs (lncRNAs) were reported to be involved in the progression of osteoarthritis (OA). The aim of this work was to explore the functional role of lncRNA nuclear-enriched abundant transcript 1 (NEAT1) in OA. Reverse-transcription quantitative polymerase chain reaction (RT-qPCR) was employed to analyze the expression of microRNA (miR-193a)-3p, NEAT1, and sex-determining region Y-box protein 5 (SOX5), as well as the levels of pro-inflammatory cytokines interleukin-6 (IL-6), IL-1ß, tumor necrosis factor-α (TNF-α), and IL-8 in OA cartilage tissue and chondrocytes. In addition, flow cytometry was used to measure the apoptosis of chondrocytes. The protein levels of extracellular matrix ACAN, collagen type II α1 chain (Col2a1), matrix metalloproteinase-3 (MMP-3), MMP-13, a disintegrin, and metalloproteinase with thrombospondin motifs (ADAMTS)-5 and SOX5 were determined using western blot analysis. Dual-luciferase reporter assay was performed to determine the target relationship among NEAT1, miR-193a-3p, and SOX5. We found that miR-193a-3p expression was downregulated, while NEAT1 and SOX5 were upregulated in OA cartilage tissue and chondrocytes. Both upregulation of miR-193a-3p and knockdown of NEAT1 suppressed inflammation, apoptosis, and reduced the protein levels of MMP-3, MMP-13, and ADAMTS-5, while elevating ACAN and Col2a1 expression in chondrocytes. NEAT1 targeted miR-193a-3p, and SOX5 was targeted by miR-193a-3p. Silencing of miR-193a-3p reversed the NEAT1 knockdown-mediated effect on the inflammation, apoptosis, and production of the extracellular matrix. The introduction of SOX5 abolished the impact of the upregulation of miR-193a-3p on inflammation, apoptosis, and production of extracellular matrix in chondrocytes. In conclusion, NEAT1/miR-193a-3p/SOX5 axis regulates cartilage matrix degradation in human OA.