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Guo, Z.

Publications and source records attributed to Guo, Z..

At least 73 records · Page 4Linked to original sources

DynPerturb:Dynamic Perturbation Modeling for Spatiotemporal Single-Cell Systems

Perturbation responses in multicellular systems are inherently spatiotemporal, governed by temporal dynamics, perturbation intensity, and tissue context. However, existing approaches rarely capture explicit spatiotemporal perturbation dynamics, limiting the ability to reconstruct how perturbations propagate over time, spread across space, and induce feedback at multiple biological scales. Here we introduce DynPerturb, a dynamic inference framework for single-cell and spatial transcriptomics that systematically models the "when-how strong-where" dimensions of perturbations. DynPerturb incorporates temporal encoding, spatial adjacency, and memory modules to capture nonlinear signal propagation and cross-regional feedback with mechanistic interpretability. Across temporal benchmarking datasets, DynPerturb consistently outperformed existing methods in regulatory link prediction, demonstrated zero-shot generalization to unseen nodes, and preserved accuracy under varying sparsity conditions and temporal resolutions. Applied to representative biological systems, DynPerturb uncovers dynamic regulatory rewiring in kidney disease, highlighting a mid-age sensitivity window and potential reversibility with early intervention; delineated a temporal fate-switching boundary between megakaryocyte-erythroid progenitors (MEPs) and granulocyte-monocyte progenitors (GMPs) during hematopoiesis; and revealed spatiotemporal interchamber signaling in murine heart development, where Igf2 perturbations induced spatial feedback shaping chamber proportioning. Collectively, these results establish DynPerturb as a unified and versatile system for dissecting dynamic perturbation effects and guiding precision intervention strategies in multicellular systems.

bioinformatics↗

Integrative Multi-omics Deciphers the Assembly Rules of the Human Skin Microbiome and Highlights Lipid-Mediated Niche Partitioning

Understanding the ecological assembly mechanisms of microbial communities is critical for deciphering host-microbiota interactions, however, such processes remain poorly characterized in cutaneous ecosystems. By profiling a non-industrialized rural cohort, this study deciphers the assembly rules governing the human skin microbiome and reveals an evolutionarily conserved core microbiota structured by niche selection. Microbial -diversity peaks when C. acnes and M. osloensis reach equilibrium, supporting the Intermediate Disturbance Hypothesis. Host lipids, rather than aqueous compounds, emerged as the primary drivers of microbial niche partitioning. We further demonstrate that C. acnes and Malassezia restricta function as core metabolic engineers, expressing diverse lipases that hydrolyze triglycerides (TGs) into free fatty acids (FFAs), thereby maintaining skin surface lipid homeostasis ([~]85% TG + FFA). Notably, virtually all skin surface FFAs are microbially derived and function as "public goods", enabling cross-feeding that supports auxotrophic members and fosters mutualistic interactions. Importantly, in vitro coculture experiments confirm that C. acnes establish a survival niche for M. restricta. Our findings support a paradigm shift from a taxonomic to a functional understanding of the skin ecosystem, underscoring microbial lipid metabolism as a central orchestrator of ecological stability and a promising target for therapeutic intervention. O_FIG O_LINKSMALLFIG WIDTH=182 HEIGHT=200 SRC="FIGDIR/small/674196v1_ufig1.gif" ALT="Figure 1"> View larger version (62K): org.highwire.dtl.DTLVardef@1274fa5org.highwire.dtl.DTLVardef@1ddfa07org.highwire.dtl.DTLVardef@49f917org.highwire.dtl.DTLVardef@807a14_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOGRAPHIC ABSTRACTC_FLOATNO C_FIG

microbiology↗

Pan-genome Analysis Reveals Hidden Diversity and Selection Signatures of Auxin Response Factors (ARFs) Associated with Breeding in Barley

Auxin Response Factors (ARFs) play a pivotal role in regulating plant growth and development, yet their evolutionary dynamics and functional divergence remain poorly understood in barley (Hordeum vulgare L.) In this study, we conducted a comprehensive genome-wide analysis of the ARF gene family across a 76-accession barley pan-genome. By integrating gene presence/absence variation (PAV) and copy number variation (CNV), phylogeny, expression profiling, transposable element (TE)-mediated regulation, and selection signatures, we characterized 1,911 ARF-coding genes and their structural, transcriptional, and functional variation at the population level. Phylogenetic analysis revealed lineage-specific expansion and dynamic duplications, particularly within the HvARF13 clade. Co-expression networks and tissue-resolved transcriptomes showed that many HvARFs are preferentially expressed in inflorescence and meristematic tissues. Selective sweep and haplotype analyses identified HvARF3 as a candidate gene under selection during European barley breeding. A favorable haplotype of HvARF3, enriched in European cultivars, was significantly associated with increased grain size and weight, demonstrating the utility of pan-genome-enabled frameworks for accelerating gene-trait association and candidate gene discovery. This study highlights the power of multi-omics integration in decoding gene family complexity and provides valuable insights for functional genomics and trait improvement in cereal crops.

plant biology↗

Physiological Reconstitution of Microtubule Doublets

The formation of microtubule doublets (MTDs) is a foundational step in cilia biogenesis, yet how B-tubule nucleation is initiated at the molecular level remains elusive. Here, we identify FAP53 as a crucial factor that promotes B-tubule assembly. Molecular dynamics simulations revealed that FAP53 alleviates steric hindrance from the -tubulin C-terminal tail and stabilizes B-tubule docking at the A-tubule surface. In vitro reconstitution demonstrated that recombinant FAP53 is sufficient to drive MTD formation under physiological tubulin conditions. In cultured HeLa cells, co-expression of CFAP53 and CFAP20--an inner junction protein--induced ectopic MTD-like structures in the cytoplasm. Furthermore, a structurally homologous protein in C. elegans, WFAP-53, localized to sensory cilia; however, when overexpressed, it triggered ectopic MTD formation in neuronal dendrites and concomitantly led to sensory cilia disassembly. These findings uncover a conserved mechanism of B-tubule initiation and underscore the necessity for spatially restricted expression of MTD assembly factors during ciliogenesis.

cell biology↗

O-SNAP: A comprehensive pipeline for spatial profiling of chromatin architecture

We present O-SNAP (Objective Single-Molecule Nuclear Architecture Profiler), a comprehensive pipeline for the automated extraction, comparison, and classification of nuclear features from single-molecule localization microscopy (SMLM) data. O-SNAP quantifies 144 interpretable, biologically grounded spatial features describing chromatin organization or histone mark distributions at nanoscale resolution. The pipeline includes modules for pairwise comparison of features using volcano plots, feature set enrichment analysis, robust feature selection and classification of cell states, and pseudotime trajectory inference. We validate O-SNAP across diverse biological contexts, including fibroblast-to-stem cell reprogramming, tendon disease, histone variant sensitivity to oxidative stress, and chondrocyte de-differentiation, demonstrating its ability to detect subtle changes in nanoscale chromatin organization across diverse biological transitions.

biophysics↗

Establishment and comparison of three kinds of chronic bacterial cystitis models in mice

Cystitis is a common urinary system disease in women. However, there are currently no effective treatment options except antibiotics. Therefore, establishing an effective and stable animal model is helpful for further study of cystitis. In this study, we established three chronic cystitis models from C57BL/6 female mice inoculated with urinary tract pathogenic Escherichia UTI89 through urethral perfusion: CPP co-infection group, seven days interval repeated infection group, and two consecutive days repeated infection group. The three models were successfully constructed, and the survival rates of the three models were 66%, 75%, 100%, respectively. The bladder infection rates of the surviving mice were 100%, 100%, 50%, respectively. H&E staining showed that the inflammation and damage were the most severe in seven days interval repeated infection group. Sirius red staining showed that the degree of fibrosis was the highest in CPP co-infection group. Immunofluorescence staining of bladder inflammatory cells showed that inflammatory cells and macrophages in the CPP co-infection group and the seven days interval repeated infection group expressed more. Basal layer epithelial cell staining showed that the epithelial cells of the three infection models had different degrees of proliferation. The three strategies can all prepare mouse chronic cystitis models with their own characteristics, and these models can be used for experimental studies related to different levels of bladder infection and fibrosis, laying a foundation for further research on the mechanism of chronic cystitis.

microbiology↗

An efficient beet severe curly top virus-based VIGS vector in Beta vulgaris

Sugar beet (Beta vulgaris L.) is one of the most important sugar crops worldwide. However, studies on sugar beet gene functions are still lagging compared to other crops due to the lack of an effective genetic manipulation. In this study, we generated an infectious clone of beet sever curly top virus (BSCTV) and engineered it into a VIGS vector. BSCTV-BvPDS can induce strong and persistent bleached PDS-silencing phenotype in 8 tested sugar beet varieties. We further efficiently silenced B. vulgaris MYB1 gene that regulating the betalain pathway in sugar beet by BSCTV-based VIGS system. Finally, we used this system to silence the effector CbNip1 of Cercospora beticola through cross-kingdom RNAi, resulting in reduced disease symptoms in sugar beet plants. Therefore, the BSCTV VIGS system can be used to study sugar beet-pathogen interactions. In summary, we have established an easy and efficiency BSCTV-based VIGS vector in sugar beet. This system will be an attractive tool for functional genomic studies for sugar beet.

plant biology↗

HER2; p53 Co-mutated Cancers Show Increased Histone Acetylation and are Sensitive to Neratinib plus Trastuzumab Deruxtecan.

In metastatic breast cancer, HER2-activating mutations often co-occur with TP53 mutations, a combination linked to poor response to neratinib and worse prognosis. To model this clinical challenge, we bred HER2 V777L transgenic mice with two TP53 mutant alleles: TP53 R172H (the murine homolog of human TP53 R175H) and TP53fl/fl, which mimics p53 truncations common in human tumors. TP53 mutations accelerated tumor development and reduced survival in HER2-mutant mice. These co-mutant tumors were resistant to neratinib but remained sensitive to exatecan, the topoisomerase I (TOP1) inhibitor payload in trastuzumab deruxtecan (T-DXd). Mechanistically, TP53 mutant tumors exhibited upregulation of histone acetylation, hypertranscription of DNA repair factors, increased chromatin accessibility, and rendered cells more susceptible to TOP1 inhibitors via G2/M arrest and apoptosis. This vulnerability is dependent on transcriptional activity of TP53 mutations, highlighting a novel strategy to treat HER2;TP53 co-mutant breast cancers using TOP1-targeted therapies. Statement of SignificanceTP53 mutations sensitize HER2-mutant cancers to TOP1 inhibitors via chromatin accessibility and hyper-transcription, supporting combination therapy with neratinib and T-DXd in TP53/HER2 co-mutant breast cancers.

cancer biology↗

Application of machine learning in the discovery of antimicrobial peptides: Exploring their potential for ulcerative colitis therapy

Ulcerative colitis (UC) is a chronic inflammatory bowel disease with rising global prevalence, yet existing treatments are not universally effective. Antimicrobial peptides (AMPs), produced by the immune system, have diverse antimicrobial and immune-regulatory functions, making them promising candidates for UC therapy. Using machine learning, we developed a machine learning-based prediction model to identify novel AMPs. The predicted peptides demonstrated significant biological activity in vitro and in vivo. In a dextran sulfate sodium-induced UC mouse model, engineered AMPs notably improved UC-related parameters, such as body weight, disease activity index (DAI), and colon length. These effects were likely mediated by modulation of Akkermansia muciniphila. This study highlights the potential of machine learning-identified AMPs as future therapeutic candidates for UC. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=154 SRC="FIGDIR/small/660148v1_ufig1.gif" ALT="Figure 1"> View larger version (50K): org.highwire.dtl.DTLVardef@187dc6borg.highwire.dtl.DTLVardef@9800deorg.highwire.dtl.DTLVardef@1611c42org.highwire.dtl.DTLVardef@866406_HPS_FORMAT_FIGEXP M_FIG C_FIG

physiology↗

Cytoprotective roles of "E3 ubiquitin ligases-NF-κB-autophagy" axis in Pacific oysters Crassostrea gigas exposed to phenanthrene

Phenanthrene (PHE), as one of the most frequently found polycyclic aromatic hydrocarbons can induce immunotoxicity, oxidative stress, and endocrine disruption in marine organisms. However, whether autophagy can be induced by PHE and the regulatory mechanism and cytoprotective roles of autophagy under PHE stress condition have not been unveiled. Our data first unveil a "E3 ubiquitin ligases-NF-{kappa}B-autophagy" axis, which play cytoprotective roles in Pacific oysters Crassostrea gigas exposed to PHE. The results of confocal laser scanning microscope, flow cytometry and transmission electron microscope confirmed that PHE could induce autophagy in the haemocytes of Pacific oysters, and the presence of autophagosomes was also confirmed. The proteomics results showed that the expression of the E3 ubiquitin ligase HUWE1, TRIM36, and autophagy-related protein 7 (ATG7) were significantly upregulated. The expression of genes of the "axis" were significantly upregulated, and the expression of genes of autophagy was downregulated after the inhibition of the NF-{kappa}B, indicating that the expression of the "axis"-related genes can be stimulated by PHE, and thus autophagy is activated. The upregulation of the expression of "axis"-related genes in mouse macrophages, further demonstrating the existence of the "axis" proposed by this study and the "axis" can be activated by PHE. Incorporating with changes of cell number, apoptosis rate, phagocytic capacity, and ROS levels of lymphocytes, we demonstrated that autophagy plays a cytoprotective role in cellular defence against PHE. This study proposed a novel pathway and supplied a comprehensive understanding of the protective role of autophagy in Pacific oysters to cope with pollutants.

cell biology↗

Pathogenicity and transmissibility of Monkeypox virus in dormice

The global spread of the monkeypox virus (MPXV) poses a significant challenge to public health, yet reliable and consistent animal models for evaluating MPXV remain limited, which to some extent restricts the advancement of treatment strategies and transmission-blocking technologies. As natural hosts, African dormice (Graphiurus spp.) represent promising candidates. However, the biological characteristics of MPXV in dormice remain largely unexplored. This study systematically evaluated the pathogenicity and transmissibility of MPXV in dormice. Experimental results demonstrated that dormice are highly susceptible to MPXV infection. Following intranasal inoculation, MPXV induced significant weight loss, lethal infections, and multi-organ pathological damage, with robust viral replication in respiratory and liver tissues. Notably, MPXV can efficiently transmit among dormice through direct contact, with one-third of the contact-exposed dormice shedding infectious viruses and two-thirds exhibiting seropositivity. In addition, one-third of the airborne exposure dormice show seropositivity, yet no infectious viruses were detected in their respiratory tissues, indicating that the airborne transmissibility of MPXV among dormice is relatively restricted. Furthermore, it was observed that infected dormice continuously released large quantities of virus-laden aerosols, with emissions peaking on 12 dpi (3.78{+/-}1.01x106 copies/dormouse/hour of respiration). Particle size analysis revealed that the viral copies in [≥]7 m coarse particles accounted for >90.9% of exhaled viral aerosols during peak shedding (8-14 dpi). These findings demonstrate that the African dormice serve as an effective animal model for assessing MPXV infection, pathogenicity, and transmission dynamics. Simultaneously, enhanced monitoring of wild dormouse populations is critical due to their potential role in MPXV transmission chains.

microbiology↗

Metagenomic Analysis Reveals Northwest Pacific Ocean as a Reservoir and Evolutionary Hub of Antibiotic Resistance Genes

O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=200 SRC="FIGDIR/small/659680v1_ufig1.gif" ALT="Figure 1"> View larger version (81K): org.highwire.dtl.DTLVardef@139e191org.highwire.dtl.DTLVardef@10834c4org.highwire.dtl.DTLVardef@1c0544aorg.highwire.dtl.DTLVardef@1ddfd8a_HPS_FORMAT_FIGEXP M_FIG O_FLOATNOGraphical abstractC_FLOATNO C_FIG Antibiotic resistance genes (ARGs) were identified as a novel type of environmental contaminants. Ocean is thought to be one of the ultimate environments where ARGs gathered. Marine ecosystems represent vast reservoirs of ARGs, yet their dynamics in open-ocean environments remain poorly characterized. Through large-scale metagenomic profiling of the Kuroshio Extension, a hydrographically dynamic region in the Northwest Pacific, we identified a striking enrichment of ARGs (1.81 x 10-3 ppm) at a frontal zone site (S30). The ARG abundance at this site exceeded coastal levels by 90-fold. Notably, multidrug resistance genes dominated this hotspot, with efflux pumps contributing 62% of the resistance mechanisms, a pattern distinct from the target-alteration strategies prevalent in other regions. The site exhibited unique microbial consortia, including pathogenic Acinetobacter (30.2% abundance) carrying clinically critical determinants (blaOXA-23, adeJ). Co-occurrence networks revealed horizontal transfer risks, linking pelagic Sphingobium to terrestrial-derived {beta}-lactamase variants. Crucially, we discovered three novel plasmid-borne resistance genes circulating in >15% of microbial populations, demonstrating open-ocean ARG diversification independent of direct anthropogenic inputs. These findings redefine oceanic frontiers as crucibles of resistance evolution, demanding urgent integration into global antimicrobial stewardship strategies.

microbiology↗

SMART: An Integrated Platform Revolutionizing Cryo-Electron Microscopy Workflow from Data Acquisition to Atomic Modeling

Recent advancements in cryo-electron microscopy (cryo-EM) have revolutionized structural biology, yet persistent workflow fragmentation between data acquisition, reconstruction, and modeling limits its full potential. This paper presents SMART, the first fully integrated cryo-EM platform unifying three critical AI-driven modules: DataSmart (automated data collection), CryoSmart (3D reconstruction), and ModelSmart (end-to-end atomic modeling). The platform embeds more than 10 distinct AI algorithms across its workflow, achieving unprecedented automation levels. These advancements not only lower the expertise barrier for cryo-EM adoption but also establish a new paradigm for AI-empowered structural biology, with broad implications for high-throughput drug discovery. This protocol provides a comprehensive delineation of the operational procedures for the SMART platform. As an example, this protocol enabled the determination of the 2.1 [A] resolution structure of TRPML1, a Ca2+-permeable, nonselective, six-transmembrane tetrameric cation channel found in late endosomes and lysosomes (LELs) of mammalian cells. This integrated workflow enables users, including those with minimal cryo-EM experience, to efficiently complete the entire pipeline from data collection to atomic model building.

bioinformatics↗

Phylogenomics of Aristolochia subg. Siphisia (Aristolochiaceae) reveals widespread incomplete lineage sorting and supports a novel pollinator-filtering hypothesis

Aristolochia subgenus Siphisia constitutes a monophyletic lineage of predominantly lianescent species, with occasional shrubs or herbs, and is characterized by remarkable diversity in perianth morphology. Members of Siphisia serve as larval hosts for endangered Lepidoptera and are widely used in traditional medicine. Despite its ecological and ethnobotanical significance, Siphisia systematics remains unresolved due to limited genomic resources and insufficient phylogenetic signal across previously sampled loci. Here, we present a phylogenomically informed framework for Siphisia, integrating 46 newly collected accessions and seven public datasets across 44 taxa. Using genome skimming ([~]30x coverage) and HybPiper, we recovered Angiosperms353 nuclear loci, including supercontigs, for phylogenetic reconstruction via concatenation and coalescent approaches. The resulting species trees resolve seven strongly supported monophyletic clades, each defined by distinct biogeographic patterns and morphological synapomorphies. Comparative plastome analyses from de novo assemblies explored quadripartite structure, plastid phylogeny, GC content, and gene synteny. Cytonuclear discordance was concentrated in species-rich Asian clades, while hybridization signals were rare and limited to deep backbone nodes in North American lineages. These results indicate that incomplete lineage sorting, rather than introgression, accounts for most gene-species tree conflicts and likely reflects strong reproductive isolation following speciation. We also revise a previously taxonomically ambiguous complex--the now well-supported A. versicolor species group--based on integrated phylogenomic and morphological evidence. Within this group, we describe five previously unrecognized cryptic species and identify a novel pollination syndrome involving floral adaptations for pollinator filtering. This syndrome may contribute to prezygotic isolation and recent diversification, and it challenges the prevailing assumption that Aristolochia pollination is universally governed by a trapping-release mechanism--suggesting this model may not apply to subg. Siphisia.

evolutionary biology↗

Synaptic proteins that aggregate and degrade slower with aging accumulate in microglia

Neurodegenerative diseases affect 1 in 12 people globally and remain incurable. Central to their pathogenesis is a loss of neuronal protein maintenance and the accumulation of protein aggregates with aging1,2. We engineered bioorthogonal tools3 which allowed us to tag the nascent neuronal proteome and study its turnover with aging, its propensity to aggregate, and its interaction with microglia. We discovered neuronal proteins degraded on average twice as slowly between 4- and 24-month-old mice with individual protein stability differing between brain regions. Further, we describe the aged neuronal aggregome encompassing 574 proteins, nearly 30% of which showed reduced degradation. The aggregome includes well-known proteins linked to disease as well as a trove of proteins previously not associated with neurodegeneration. Unexpectedly, we found 274 neuronal proteins accumulated in microglia with 65% also displaying reduced degradation and/or aggregation with age. Among these proteins, synaptic proteins were highly enriched, suggesting a cascade of events emanating from impaired synaptic protein turnover and aggregation to the disposal of these proteins, possibly by the engulfment of synapses by microglia. These findings reveal the dramatic loss of neuronal proteome maintenance with aging which could be causal for age-related synapse loss and cognitive decline.

neuroscience↗

Quantitative RNA pseudouridine landscape reveals dynamic modification patterns and evolutionary conservation across bacterial species

Pseudouridine ({Psi}) modifications are the most abundant RNA modifications; however, their distribution and functional significance in bacteria remain largely unexplored compared to eukaryotic systems. In this study, we present the first transcriptome-wide and quantitative mapping of {Psi} modifications across five diverse bacterial species (Bacillus cereus, Escherichia coli, Klebsiella pneumoniae, Pseudomonas aeruginosa, and Pseudomonas syringae) at single-base resolution, utilizing the optimized BID-seq method for bacterial RNA. Our analysis revealed growth phase-dependent dynamics of pseudouridylation in bacterial tRNA and mRNA, particularly in genes enriched in core metabolic pathways. Comparative analysis demonstrated evolutionarily conserved features of {Psi} modifications, such as dominant motif contexts, {Psi} clustering within operons, etc. Functional analysis indicated {Psi} modifications influence bacterial mRNA stability, translation, and interactions with specific RNA-binding proteins (RBPs) in response to changing cellular demands during growth phase transitions. The integrated computational analysis on local RNA architecture was conducted to elucidate the structure-dependent {Psi} modifications in bacterial RNA. Furthermore, we developed an integrated deep learning framework, combining Transformer-GNN-based neural networks (pseU_NN) to capture both RNA sequence and structural features for effective prediction of {Psi}-modified sites. Overall, our study provides valuable insights into the landscapes of bacterial RNA {Psi} modifications and establishes a foundation for future mechanistic investigations into the functions of {Psi} in bacterial RNA regulation.

microbiology↗

Ciliated cells promote high infectious potential of influenza A virus through the efficient intracellular activation of hemagglutinin

Influenza viruses utilize host proteases to activate the viral fusion protein, hemagglutinin (HA), into its fusion-competent form. Although proteolytic activation of HA is essential for virus replication, the cell-type dependence of HA activation within the airway epithelium and the subcellular location(s) in which it occurs are not well-established. To address these questions, we investigated the proteolytic activation of HA in differentiated human airway epithelial cells using contemporary and historical H1N1 and H3N2 strains. We find that activation is efficient across viral strains and subtypes but depends on cellular tropism, with ciliated cells activating HA more effectively than non-ciliated cells. Similar to prior observations in immortalized cell lines, we find that HA activation occurs intracellularly, constraining the antiviral activity of host-directed protease inhibitors. These results establish that HA activation within the airway epithelium depends on cellular tropism, and identify important considerations for the development of protease inhibitors as antivirals. ImportanceInfluenza entry requires the proteolytic activation of the viral fusion protein, hemagglutinin (HA). Activation occurs as new viruses are produced by infected cells. Efficient proteolytic activation is critical for viral pathogenesis, and inhibiting the requisite proteases could provide an effective host-directed antiviral strategy. To understand cellular constraints on HA activation and its sensitivity to inhibitors, we use complementary approaches to investigate these processes in differentiated airway epithelial cells. We find that ciliated cells activate HA with higher efficiency than non-ciliated cell types, establishing a new mechanism through which cellular tropism and virus infectious potential are connected. We also establish that HA activation begins in the Golgi, which may contribute to the limited the efficacy of inhibitors we observe despite their high in vitro potency.

microbiology↗

Ancient DNA Reveals Hominoid Evolution: Intermediate DNA Sequences and Advances in Molecular Paleontology

AbstractFossils and ancient crude pottery vessels function as physical "DNA containers," preserving oriDNA (original, in situ DNA) and accumulating eDNA (environmental DNA) over time. Ancient DNA (aDNA) serves as molecular fossils, chronicling evolutionaryhistory. Using "nano-affinitybead technology", we extracted and sequenced DNAfrom Lycoptera fossils in the Jehol region and a "round-bellied jar (Jar)" from the Erlitou period in Guangwu Town, yielding 236,545 primate sequences from the fossils and 86,908 from the pottery. We observed that the AFF value of DNA sequences negatively corre lates with species divergence time1, offering a quantitative measure of DNA preservation and host divergence. Some fragments distinct from modern genomic sequences, termed "intermediate DNAsequences" (IDS), have been identified. Many IDS exhibit an upper age limit, preserving characteristics of the last common ancestor (LCA) of the Hominidae and offering molecular insights into "Darwins puzzle". Among IDS, the SRRA subtype (Sequence Reversal and Rearrangement), identified in mRNA-coding exonic sequences, arises from the incorporation of a complementary antisense strand upstream of the sense strand, either adjacent to it or separated bya sequence interval. This introduces a novel post-transcriptional regulatory mechanism at the mRNA level, driven by SRRA, which presets hairpin structures and Indels in the UTR or CDS of exonic sequences, modulating gene variation. We propose: "SRRAs played a critical trial-and-error role in early Hominidae evolution, facilitating adaptive genomic changes, with some SRRA sequences later excised from exons", positioning SRRAas an evolutionary "genetic switch". Additionally, seven species -specific fragments (SSFs) of non-human primates (NHPs) linked to Asian Homo erectus were identified in the fossils, and pottery DNA reveale d sequences from tropical species (e.g., zebrass, oil palms), providing evidence of climate-driven local extinction and supporting paleo-ecological and paleo-environmental reconstruction. This method of analyzing aDNA from non-skeletal materials opens new avenues in paleontology, archaeology, and geology, guiding the tracing of ancient migration patterns and fossil searches. DNAfragments preserved within "DNA containers " exhibit an "old-few, new-many" turnover pattern, with many aDNA fragments displaying non-deamination. This evidence challenges prevailing perspectives, the authenticity criteria for aDNA, and the capabilities and scope of the traditional research method, necessitating a thorough reevaluation of the relevant knowledge framework. Furthermore, this study opens new opportunities for frontier research.

paleontology↗