Biology subjects

Tu, Q.

Publications and source records attributed to Tu, Q..

8 recordsLinked to original sources

bioRxiv2026

Artificial Recombination of Nonribosomal Peptide Synthetases Rapidly Evolves Natural Products

Efficient engineering of nonribosomal peptide synthetases (NRPSs) is a key strategy for expanding valuable peptide natural products. Current bioinformatics-guided approaches are often constrained by a set of predefined fusion sites, remaining experimentally challenging in most NRPS systems. Here we present the Recombineering Accelerated Evolution (RACE), which harnesses Red/ET recombineering mediated partially matched homologous recombination to recapitulate recombination-driven NRPS evolution on a highly accelerated timescale. Application of RACE to six known NRPS gene clusters generated 830 recombinants and yielded over 600 novel peptides including novel bis-lipopeptides. These recombinants reveal 112 previously unrecognized recombination fusion sites, providing an extensive landscape for NRPS evolution and more useful resources for guiding NRPS engineering. The RACE establishes a new paradigm for programmable NRPS evolution and enables rapid discovery of bioactive peptides.

synthetic biology↗

bioRxiv2026

CCycDB: an integrative knowledgebase to fingerprint microbially mediated carbon cycling processes

Microorganisms play essential roles in mediating biogeochemical cycling of carbon across Earths ecosystems. Understanding the processes and underlying mechanisms for microbially mediated carbon cycling is therefore critical for advancing global ecology and climate change research. To comprehensively depict these complex biogeochemical processes, we developed CCycDB, a knowledge-based functional gene database, to accurately fingerprint microbially-mediated carbon cycling pathways and gene families, particularly from shotgun metagenomes. The CCycDB database comprises 4,676 gene families classified into six major functional categories, further structured into 45 level-1 and 188 level-2 sub-categories, encompassing a total of 10,991,724 high-quality reference sequences. Validation using both synthetic and real-world datasets demonstrated that CCycDB outperforms existing orthology databases in terms of accuracy, coverage and specificity. By directly targeting carbon-cycling functional gene families, CCycDB provided promising routines to reconstruct both functional gene and taxonomic profiles associated with microbially mediated carbon cycling. Application of CCycDB to shotgun metagenomes from diverse and complex ecosystems revealed pronounced habitat-specific differences in carbon cycling processes and their associated microbial taxa. Collectively, CCycDB provides a powerful and reliable tool for profiling carbon cycling processes from both functional and taxonomic perspectives in complex ecosystems. CCycDB is accessible at https://ccycdb.github.io/. Impact StatementThe microbially mediated carbon cycling processes are the most complex biogeochemical processes in the Earths biosphere, playing profound regulatory roles on global climate changes. A key bottleneck in linking microbial communities to global change is the lack of integrated tools for comprehensive carbon cycle profiling. Here, we present CCycDB, a tool that serves a dual purpose--first being a reference database that obtains functional gene and taxonomic profiles and functioning as a customized routine for efficiently aligning sequences and querying associated functional information. CCycDB enables researchers to accurately link microbial community dynamics to carbon cycling and transforming pathways, thereby advancing integrated global change studies with microbes and ecological research via complex metagenomic datasets.

microbiology↗

bioRxiv2024

Host-derived Lactobacillus plantarum alleviates hyperuricemia by improving gut microbial community and hydrolase-mediated degradation of purine nucleosides

AbstractGut microbiota has been considered to be associated with the development of hyperuricemia (HUA) and gout. Some prebiotics from different sources had the potential alleviation function in HUA. However, whether host-derived potential probiotics, like Lactobacillus, from the gut of HUA animals could prevent the development of HUA is still uncertain. In this study, we established a HUA geese model and isolated a Lactobacillus plantarum strain, SQ001, from the cecum of HUA geese. Nucleoside co-culture and metabolomics analyses revealed that L. plantarum SQ001 is involved in the absorption and hydrolysis of nucleosides. Whole genome analysis showed there are four genes related with nucleosides hydrolysis in L. plantarum SQ001. The function of iunH, a nucleoside hydrolase gene, was further confirmed by heterologous expression and knockout assays. Oral administration of L. plantarum SQ001 in HUA geese models upregulated the Lactobacillus abundance and reduced serum uric acid (UA) levels. Likewise, in mouse models, L. plantarum SQ001 increased the L. plantarum abundance and lowered serum UA levels by reducing hepatic UA synthesis protein XO and renal UA reabsorption protein GLUT9 expression, while increasing renal UA excretion protein ABCG2 expression. Our findings demonstrated that host-derived probiotics from geese could alleviate gut microbe dysbiosis and HUA in its host and mouse model. This study provides insights into the potential probiotic role of Lactobacillus plantarum in HUA or gout therapy. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=83 SRC="FIGDIR/small/606206v1_ufig1.gif" ALT="Figure 1"> View larger version (36K): org.highwire.dtl.DTLVardef@698e7eorg.highwire.dtl.DTLVardef@a2091org.highwire.dtl.DTLVardef@e0348aorg.highwire.dtl.DTLVardef@19958ad_HPS_FORMAT_FIGEXP M_FIG C_FIG

microbiology↗

bioRxiv2024

From Understudied to Understood: Multi-Omics Analysis with MiniENCODE Exemplified by Zebrafish

Building multi-omics resources for understudied organisms requires assay selection, public-data curation, gene identifier handling, portal deployment, and visualization, yet these tasks are rarely packaged into a reusable framework. To fill this gap, we developed the mini Omics Data Portal (miniODP), which combines species pages, gene-centric modules, genome browsing, and sequence search with configuration files, species onboarding workflows, and demonstration data for self-deployment. Alongside the software, we propose miniENCODE core assays: a reduced RNA-seq, ATAC-seq, and H3K27ac profiling set for regulatory analysis. Current miniODP includes seven species, covering 3,568 bulk runs, 3.61 million cells, and 1,865 genome-browser tracks. Matched core-assay datasets support regulatory outputs. As a zebrafish benchmark, using datasets from three core assays and 17 samples, we identified 52,350 enhancer-like signatures (ELSs) and constructed ELS-to-gene linkages and gene regulatory networks (GRNs). Genes near H3K27ac-supported ELSs were expressed at higher levels than those near ATAC-only distal peaks. Literature curation of top TFs from zebrafish and cattle GRNs found 19 direct, 15 indirect, and six unsupported cases among 40 candidates. Datasets lacking matched core assays still provide browsing, visualization, and search functions. miniODP serves as a reusable framework for constructing and extending multi-omics resources for understudied organisms. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=76 SRC="FIGDIR/small/573815v3_ufig1.gif" ALT="Figure 1"> View larger version (32K): org.highwire.dtl.DTLVardef@1542265org.highwire.dtl.DTLVardef@9e5424org.highwire.dtl.DTLVardef@a630d5org.highwire.dtl.DTLVardef@d0163c_HPS_FORMAT_FIGEXP M_FIG C_FIG

genomics↗

bioRxiv2023

Dendritic cell-derived lncRNA in patients with acute coronary syndrome

BackgroundLong non-coding RNA (lncRNA) and dendritic cells (DC) play an important role in the occurrence and development of acute coronary syndrome (ACS). However, the role and mechanism of DC-derived lncRNA in patients with ACS still remains understudied. ObjectiveTo investigate the expression difference and role of lncRNA in monocyte-derived DC(moDC) in patients with acute coronary syndrome(ACS). Methods and ResultsThe subjects were divided into 4 groups: (1) healthy control group (CON), (2) unstable angina group (UA), (3) non-ST elevation myocardial infarction group (NSEMI or NST) and (4) ST elevation myocardial infarction group (STEMI or ST). Peripheral blood was extracted and isolated to obtain mononuclear cells (PBMC). After induction into moDC, morphology was observed by electron microscope and identified by flow cytometry (FCM) (CD80, CD86, CD11c, CD14, HLA-DR), and morphological and functional differences were compared. The differentially expressed lncRNA were screened by gene sequencing, and the biological functions of which were predicted by GO and KEGG and the correlation between candidate lncRNA and target genes was analyzed. The expression levels of markers, signaling pathways, inflammatory factors and target gene were performed by FCM, RT-PCR, WB and ELISA after the candidate lncRNA were over-expressed or silenced. Electron microscope showed that the cells were suspended cells of dendritic pseudopodia. FCM showed that the expression levels of DC markers CD11c (99.02{+/-}0.12%) and HLA-DR (99.32{+/-}0.08%) were high, while the expression levels of CD80 (24.27{+/-}0.99%) and CD86 (32.38{+/-}0.59%) were low. The number of differentially expressed lncRNA screened by gene sequencing was as follows: CON vs UA, 3; CON vs. NST, 49; CON vs ST, 35; UA vs. NST, 115; UA vs ST, 113; ST vs NST, 4. The results of FCM, RT-PCR, WB and ELISA showed that the expression levels of markers (CD80, CD86, HLA-DR), signaling pathways (p-PI3K, p-AKT), inflammatory factors (IL-6 and IL-12p70) and target gene (CCL14) were increased after over-expression of CCL15-CCL14; On the contrary, its expression level was decreased. ConclusionsThere are differences in moDC morphology and function and lncRNA expression in different types of ACS patients, and the differentially expressed lncRNA (CCL15-CCL14) regulates the function of moDC.

immunology↗

bioRxiv2023

The diversity and ecological significance of microbial traits potentially involved in B12 biosynthesis in the global ocean

Cobalamin (B12), an essential nutrient and growth cofactor for many living organisms on the Earth, can be fully synthesized only by selected prokaryotes in nature. Therefore, microbial communities related with B12 biosynthesis could serve as an example subsystem to disentangle the underlying ecological mechanisms balancing the function and taxonomy of complex functional assemblages. By anchoring microbial traits potentially involved in B12 biosynthesis, we depict the biogeographic patterns of B12 biosynthesis genes and their carrying taxa in the global ocean, in light of the limitation to detect de novo B12 synthesizers via metagenomes alone. Both the taxonomic and functional composition of B12 biosynthesis genes were strongly shaped by depth, differentiating epipelagic from mesopelagic zones. The functional genes were relatively stably distributed across different oceans, but their carrying taxa varied considerably, showing clear functional redundancy of microbial systems. Microbial taxa carrying B12 biosynthesis genes in the surface water were influenced by environmental factors such as temperature, oxygen and nitrate. However, the composition of functional genes was weakly associated with these environmental factors. Null model analyses demonstrated that determinism governed the compositional variation of B12 biosynthesis genes, whereas a higher degree of stochasticity was associated with taxonomic variations. Significant associations were observed between chlorophyll a concentration and B12 biosynthesis traits, indicating their importance in global ocean primary production. Conclusively, this study revealed an essential ecological mechanism governing the assembly of microbes in nature: the environment selects function rather than taxonomy; functional redundancy underlies stochastic community assembly. Impact StatementA central question in ecology is how a galaxy of microbial taxa is assembled and distributed across space and through time, executing essential ecosystem functions. By anchoring microbial functional traits potentially involved in B12 biosynthesis and their carrying microbial taxa in the global ocean, this study addresses essential ecological questions from functional and taxonomic angles. Integrating multiple lines of evidence, we show that the ecosystem selects functional traits rather than taxonomic groups, and functional redundancy underlies stochastic taxonomic community assembly. Also, microbial communities potentially involved in B12 biosynthesis are significantly associated with chlorophyll a concentration, demonstrating their importance in global ocean primary production. This study provides valuable mechanistic insights into the complex microbial community assembly in natural ecosystems.

microbiology↗

bioRxiv2020

Single-cell immune landscape of human recurrent spontaneous abortion

Successful pregnancy in placental mammals substantially depends on the establishment of maternal immune tolerance to the semi-allogenic fetus. Disorders in this process are tightly associated with adverse pregnancy outcomes including recurrent spontaneous abortion (RSA). However, an in-depth understanding of the disorders from the aspect of systematic and decidual immune environment in RSA remains largely lacking. In this study, we utilized single-cell RNA-sequencing to comparably analyze the cellular and molecular signatures of decidual and peripheral leukocytes in normal and RSA pregnancies at the early stage of gestation. Integrative analysis identified 22 distinct cell clusters in total, and a dramatic difference in leukocyte subsets and molecular properties in RSA cases was revealed. Specifically, the cytotoxic properties of CD8T effector, NK, and MAIT cells in peripheral blood indicated apparently enhanced immune inflammatory status, and the subpopulation proportions and ligand-receptor interactions of the decidual leukocyte subsets demonstrated preferential immune activation in RSA patients. The molecular features, spatial distribution and the developmental trajectories of five decidual NK (dNK) subsets were illustrated. The proportion of a dNK subset responsible for fetal protection was reduced, while the ratio of another dNK subset with cytotoxic and immune-active signature was significantly increased. Notably, a unique pro-inflammatory CD56+CD16+ dNK subpopulation was substantially accumulated in RSA decidua. These findings reveal a comprehensive cellular and molecular atlas of decidual and peripheral leukocytes in human early pregnancy, which provides an in-depth insight into the immune pathogenesis for early pregnancy loss.

immunology↗

bioRxiv2020

Loss of hepatic aldolase B activates Akt and promotes hepatocellular carcinogenesis by destabilizing Aldob/Akt/PP2A protein complex

Loss of hepatic fructose-1, 6-bisphosphate aldolase B (Aldob) leads to a paradoxical upregulation of glucose metabolism to favor hepatocellular carcinogenesis but the upstream signaling events remain poorly defined. Akt is highly activated in HCC and targeting Akt is being explored as a potential therapy for HCC. Herein we demonstrate that Aldob suppresses Akt activity through a protein complex containing Aldob, Akt, and protein phosphatase 2A (PP2A), leading to inhibition of cell viability, cell cycle progression, glucose metabolism and tumor growth. Interestingly, Aldob directly interacts with phosphorylated Akt (p-Akt) and promotes the recruitment of PP2A to dephosphorylate p-Akt, and this scaffolding effect of Aldob is independent of its enzymatic activity. Loss of Aldob or disruption of Aldob/Akt interaction in Aldob R304A mutant restores Akt activity and tumor promoting effects. Consistently, Aldob and p-Akt expression are inversely correlated in human HCC tissues, and Aldob downregulation coupled with p-Akt upregulation predicts a poor prognosis for HCC. We have further discovered that a specific small-molecule activator of PP2A (SMAP) efficiently attenuates HCC tumorigenesis in Aldob-deficient cell lines and xenografts. Our work reveals a novel non-glycolytic role of Aldob in negative regulation of Akt activation, suggesting that inhibiting Akt activity and reactivating PP2A may be a potential therapeutic approach for HCC treatment.

cancer biology↗