Pyran- and furanocoumarins are key representatives of tetrahydropyrans and tetrahydrofurans, respectively, exhibiting diverse physiological and medical bioactivities. However, the biosynthetic mechanisms for their core structures remain poorly understood. Here we combined multiomics analyses of biosynthetic enzymes in Peucedanum praeruptorum and in vitro functional verification and identified two types of key enzymes critical for pyran and furan ring biosynthesis in plants. These included three distinct P. praeruptorum prenyltransferases (PpPT1-3) responsible for the prenylation of the simple coumarin skeleton 7 into linear or angular precursors, and two novel CYP450 cyclases (PpDC and PpOC) crucial for the cyclization of the linear/angular precursors into either tetrahydropyran or tetrahydrofuran scaffolds. Biochemical analyses of cyclases indicated that acid/base-assisted epoxide ring opening contributed to the enzyme-catalyzed tetrahydropyran and tetrahydrofuran ring refactoring. The possible acid/base-assisted catalytic mechanisms of the identified cyclases were theoretically investigated and assessed using site-specific mutagenesis. We identified two possible acidic amino acids Glu303 in PpDC and Asp301 in PpOC as vital in the catalytic process. This study provides new enzymatic tools in the epoxide formation/epoxide-opening mediated cascade reaction and exemplifies how plants become chemically diverse in terms of enzyme function and catalytic process.

Objective:To investigate the clinical and genetic features of a child with Dyschromatosis symmetrica hereditaria (DSH) and variant of the ADAR1 gene. Methods:A child who was admitted to the Department of Dermatology of the First Affiliated Hospital of Zhengzhou University in June 2020 due to irregular pigmented maculopapular rash on the dorsum of hands was selected as the study subject. Whole exome sequencing (WES) was carried out for the child and his similarly affected father, and Sanger sequencing was used to verify the candidate variant. SWISS-MODEL was used to predict the secondary and tertiary structures of the wild-type and mutant ADAR1 proteins.Results:The child, a 13-year-old boy, had symmetrical hyperpigmented and depigmented spots on the back of his hands and was clinically diagnosed with DSH. WES and Sanger sequencing results showed that he and his father had both harbored a heterozygous c. 2858dup (p.T954Dfs*20) truncating variant in exon 10 of the ADAR1 gene. Based on the guidelines from the American College of Medical Genetics and Genomics, the variant was predicted as pathogenic (PVS1+ PM2_Supporting+ PM1+ PP3). Conclusion:The c. 2858dup (p.T954Dfs*20) variant of the ADAR1 gene probably underlay the DSH in this pedigree.

OBJECTIVE: To analysis variants of COL4A5 gene in two Chinese pedigrees affected with Alport syndrome (AS) and provide prenatal diagnosis for them. METHODS: Two unrelated ethnic Han Chinese pedigrees who had visited the First Affiliated Hospital of Zhengzhou University respectively in September 2018 and January 2020 were selected as the study subjects. Clinical data were collected, and genomic DNA was extracted from peripheral venous blood and amniotic fluid samples for genetic testing. Following next generation sequencing, candidate variants of the COL4A5 gene were verified by Sanger sequencing and bioinformatic analysis. The gender of the fetuses was determined by the presence of sex-determining region on Y (SRY). RESULTS: Genetic testing revealed that the proband and a fetus from pedigree 1 had both harbored a c.2723G>A (p.Gly908Glu) variant in exon 32 of the COL4A5 gene, whilst the proband and a fetus from pedigree 2 had both harbored a c.3817G>A (p.Gly1273Asp) variant in exon 44 of the COL4A5 gene. Based on the guidelines from the American College of Medical Genetics and Genomics (ACMG), both variants were classified as likely pathogenic (PP2+PM2_Supporting). Following exclusion of maternal contamination, PCR amplification of the SRY region indicated that both fetuses were males. CONCLUSION The c.2723G>A (p.Gly908Glu) and c.3817G>A (p.Gly1273Asp) variants of the COL4A5 gene probably underlay the AS in the two pedigrees. Detection of the SRY region can reliably identify the fetal sex, which is conducive to the prenatal diagnosis. Above results have also enriched the mutational spectrum of the COL4A5 gene and provided a reference for correlating the genotype and phenotype of the AS.
Female ; Humans ; Male ; Pregnancy ; Collagen Type IV/genetics* ; East Asian People ; Genetic Testing ; Nephritis, Hereditary/genetics* ; Pedigree ; Prenatal Diagnosis

In order to study the involatile chemical components in Moutai-flavored distiller’s grains, the Moutai-flavored distiller’s grains were extracted with 75% ethanol, followed by extraction with petroleum ether, ethyl acetate, and n-butanol. Silica gel, ODS, sephadex LH-20, and preparative HPLC were used to separate and identify the petroleum ether and ethyl acetate layers.ESI-MS and NMR were used to identify the compounds, which were respectively identified as pentadecanoic acid (1), palmitic acid (2), trans-2-decenoic acid (3), n-nonyl octadecanoate (4), ethyl octadecanoate (5), ethyl linoleate (6), luric acid (7), 1, 3-dicaprylyl-2-linoleylglycerin (8), cyclic (phenylalanine-proline) (9), cyclo-(proline-leucine) (10), 3, 6-bis-(2-methylpropyl)-2,5-dione piperazine (11), 4-hydroxyphenethyl alcohol (12), 2,4-dihydroxybenzoic acid (13), stigmasterol (14), 2-furancarboxylic acid (15), valine (16), L-alanine acyl-L-proline (17), dihydroquercetin (18), 5, 7, 3'', 4''-tetrahydroxyflavonoids (19), quercetin (20), and naringenin (21). Compounds 1-21 were isolated from distiller’s grains for the first time.

The first rate-limiting enzyme of the serine synthesis pathway (SSP), phosphoglycerate dehydrogenase (PHGDH), is hyperactive in multiple tumors, which leads to the activation of SSP and promotes tumorigenesis. However, only a few inhibitors of PHGDH have been discovered to date, especially the covalent inhibitors of PHGDH. Here, we identified withangulatin A (WA), a natural small molecule, as a novel covalent inhibitor of PHGDH. Affinity-based protein profiling identified that WA could directly bind to PHGDH and inactivate the enzyme activity of PHGDH. Biolayer interferometry and LC-MS/MS analysis further demonstrated the selective covalent binding of WA to the cysteine 295 residue (Cys295) of PHGDH. With the covalent modification of Cys295, WA blocked the substrate-binding domain (SBD) of PHGDH and exerted an allosteric effect to induce PHGDH inactivation. Further studies revealed that with the inhibition of PHGDH mediated by WA, the glutathione synthesis was decreased and intracellular levels of reactive oxygen species (ROS) were elevated, leading to the inhibition of tumor proliferation. This study indicates WA as a novel PHGDH covalent inhibitor, which identifies Cys295 as a novel allosteric regulatory site of PHGDH and holds great potential in developing anti-tumor agents for targeting PHGDH.

Although multifarious tumor-targeting modifications of nanoparticulate systems have been attempted in joint efforts by our predecessors, it remains challenging for nanomedicine to traverse physiological barriers involving blood vessels, tissues, and cell barriers to thereafter demonstrate excellent antitumor effects. To further overcome these inherent obstacles, we designed and prepared mycoplasma membrane (MM)-fused liposomes (LPs) with the goal of employing circulating neutrophils with the advantage of inflammatory cytokine-guided autonomous tumor localization to transport nanoparticles. We also utilized in vivo neutrophil activation induced by the liposomal form of the immune activator resiquimod (LPs-R848). Fused LPs preparations retained mycoplasma pathogen characteristics and achieved rapid recognition and endocytosis by activated neutrophils stimulated by LPs-R848. The enhanced neutrophil infiltration in homing of the inflammatory tumor microenvironment allowed more nanoparticles to be delivered into solid tumors. Facilitated by the formation of neutrophil extracellular traps (NETs), podophyllotoxin (POD)-loaded MM-fused LPs (MM-LPs-POD) were concomitantly released from neutrophils and subsequently engulfed by tumor cells during inflammation. MM-LPs-POD displayed superior suppression efficacy of tumor growth and lung metastasis in a 4T1 breast tumor model. Overall, such a strategy of pathogen-mimicking nanoparticles hijacking neutrophils in situ combined with enhanced neutrophil infiltration indeed elevates the potential of chemotherapeutics for tumor targeting therapy.

Three-dimensional bioprinting technology has shown excellent application prospect in recent years in the field of tissue engineering and regenerative medicine due to its ability to fabricate tissue-engineered grafts with delicate structures through programmed control. Here we briefly describe the basic steps of bioprinting, discuss the recent applications of bioprinting in tissue engineering and analyze the general strategies for bioprinting functional tissue constructs. We review three types of bioprinting approaches (sacrificial bioprinting, hydrogel-embedded bioprinting, gradient bioprinting) with a focus on nozzle-based techniques and respective advantages of extrusion bioprinters, and finally summarize the limitations of current technologies and provide an outlook on their future development.

Three-dimensional bioprinting technology has shown excellent application prospect in recent years in the field of tissue engineering and regenerative medicine due to its ability to fabricate tissue-engineered grafts with delicate structures through programmed control. Here we briefly describe the basic steps of bioprinting, discuss the recent applications of bioprinting in tissue engineering and analyze the general strategies for bioprinting functional tissue constructs. We review three types of bioprinting approaches (sacrificial bioprinting, hydrogel-embedded bioprinting, gradient bioprinting) with a focus on nozzle-based techniques and respective advantages of extrusion bioprinters, and finally summarize the limitations of current technologies and provide an outlook on their future development.

OBJECTIVE: To explore the genetic basis for a Chinese pedigree affected with X-linked hereditary Alport syndrome. METHODS: Next generation sequencing was carried out for the pedigree. Candidate variant was validated by Sanger sequencing. Pathological changes of renal basement membrane and expression of COL4A5 protein were analyzed by renal biopsy and immunofluorescence assay, respectively. RESULTS: All patients from the pedigree manifested progressive renal damage, gross hematuria, proteinuria and nephrotic syndrome. Renal biopsy of the proband revealed thickening of the basement membrane. No expression of the COL4A5 gene was detected by immunofluorescence. High-throughput sequencing and Sanger sequencing indicated that the proband has carried a c.3706delC (p.1236Pfs*69) variant in exon 41 of the COL4A5 gene. The same variant was also found in his mother and two brothers whom were similarly affected. CONCLUSION The novel c.3706delC (p.1236Pfs*69) variant of the COL4A5 gene probably underlay the pathogenesis of X-linked hereditary Alport syndrome in this pedigree. Above findings have enriched the spectrum of COL4A5 gene variants and provided a basis for the diagnosis and genetic counseling for the pedigree.
Collagen Type IV/genetics* ; Hematuria ; High-Throughput Nucleotide Sequencing ; Humans ; Male ; Mutation ; Nephritis, Hereditary/genetics* ; Pedigree

Limb and CNS expressed 1 like (LIX1L) is over-expressed in several types of tumors. However, the function of LIX1L in glucose metabolism and hepatocellular carcinoma (HCC) progression remains elusive. Here we report that LIX1L is over-expressed in human HCC tissues, which predicts unfavorable prognosis. LIX1L deficiency