Journal of Genetics and Genomics最新文献

Andrographis paniculata is a distinctive medicinal plant that produces andrographolide-related metabolites, a class of diterpenoid compounds with potent anti-inflammatory activities. To elucidate the genetic mechanisms underlying the biosynthesis of these compounds, we perform comprehensive metabolic profiling and whole-genome resequencing on a natural population of A. paniculata. Population structure analysis reveals four distinct subgroups characterized by low intra-group genetic diversity but significant inter-group differentiation. Through metabolome-based genome-wide association study, we identify a significant locus associated with 14-deoxyandrographolide content. This locus harbors the candidate gene ApNB-ARC25 (CXN00004106), which encodes an NB-ARC domain-containing resistance protein. Functional characterization using virus-induced gene silencing shows that silencing of ApNB-ARC25 significantly reduces andrographolide accumulation and downregulates expressions of key genes in the andrographolide biosynthetic pathway. Heterologous overexpression of ApNB-ARC25 in rice not only improves resistance to blast disease but also enhances diterpenoid phytoalexin production. Our findings reveal that ApNB-ARC25 promotes diterpenoid accumulation and andrographolide biosynthesis by upregulating key genes involved in terpenoid backbone formation and diterpenoid synthesis. This work not only expands the functional understanding of the ApNB-ARC gene family but also provides a genetic resource for enhancing valuable compound accumulation in medicinal plants, offering important insights into the molecular regulation of medicinal metabolite biosynthesis.

Leaf adaxial-abaxial polarity is fundamental for plant morphogenesis and environmental adaptation through asymmetric cell differentiation. Emerging evidence reveals dorsoventral metabolic gradients act downstream of transcriptional networks to fine-tune cellular specialization. While conserved transcription factors (e.g., HD-ZIP III, KANADI) establish initial polarity, the molecular networks driving position-specific cellular differentiation and their integration with metabolic adaptation remain unclear. Leveraging single-nucleus and spatial transcriptomics, we resolve major cell classes (mesophyll, epidermal, and vascular-associated) and their adaxial-abaxial subtypes, revealing dorsoventral polarity in transcriptional profiles and metabolic pathways. Adaxial cells are enriched in phenylpropanoid/flavonoid biosynthesis, while abaxial cells show preferential activation of stress and hormone signaling. Notably, we identify MYC2 as a key regulator of adaxial cuticle biosynthesis, binding to promoters of lipid biosynthetic and transport genes (e.g., CER10, LTPG1) and promoting cuticle thickening. Our study uncovers how positional identity shapes transcriptional and metabolic polarity in leaves, with MYC2 emerging as a central regulator coordinating organ-specific adaptations. These findings provide insights into the spatial regulation of plant development and stress resilience, offering potential strategies for engineering stress-tolerant woody crops.

Transcriptional regulation is a highly dynamic process in which nascent RNAs provide the most immediate readout of transcriptional activity. Precise mapping of transcription start sites (TSSs) is therefore critical for understanding promoter architecture and gene regulation, yet remains technically challenging. Here, we introduce Nascent Strand-Specific RNA sequencing (NSS-seq), a robust and streamlined method for genome-wide profiling of the capped 5' ends of nascent RNAs. By directly capturing transcription initiation events, NSS-seq overcomes the temporal delay inherent to conventional RNA-seq and enables time-resolved interrogation of transcriptional dynamics. Applied to interferon-gamma (IFN-γ)-stimulation, NSS-seq uncovered previously unrecognized IFN-γ-responsive genes and transient transcription factor activation patterns underlying interferon-mediated tumor-suppressive functions. Together, NSS-seq provides a cost-effective and technically accessible platform for dissecting promoter-level regulatory dynamics during cellular responses.

Through natural and artificial selection, goats develop distinct hair phenotypes driven by genomic variations, such as structural variations (SVs). The fatty acid desaturase (FADS) family plays an important role in hair follicle (HF) growth, yet its molecular mechanisms remain unclear. In this study, we construct a goat graph-based pangenome containing 99,792 non-redundant presence-absence variations (PAVs) from 16 goat breeds. Using this pangenome, we identify 15,866 allelic variants of PAVs with distinct dominant frequencies (dPAVs) from the resequencing data of 300 goats. Among them, 1290 dPAVs regulate the expression of 772 corresponding genes in cashmere goats (CGs) with different hair types over 12 months. We identify an expanded FADS2P1 gene family with two intact copies and one truncated copy within segmental duplications. An intron deletion in the truncated FADS2P1 copy shows population-specific distribution patterns among goats with cashmere traits. All FADS2P1 copies are significantly upregulated in short-hair CGs, and their expression levels are negatively correlated with oleic acid (OA) levels. Functional validation in FADS2P1 knock-in mice indicates a slower hair growth rate and reduced HF numbers. These findings demonstrate that SV-driven FADS2P1 expression regulates HF development and growth through OA metabolism, providing insights into how PAVs influence complex phenotypes.

Protein kinases are pivotal regulators of cellular signaling, and their genetic variations are frequently implicated in diseases. Although numerous kinase mutations have been identified as drivers of altered activity, with a few successfully targeted therapeutically, the functional impact of most variants remains uncharacterized. To bridge this gap, we curate a comprehensive dataset that contains 2553 experimentally validated kinase activity-related key alterations (KAKAs) from the literature. While many mutations outside canonical functional regions are known to affect kinase activity, systematic methods to predict their functional consequences are lacking. Consequently, we develop a computational method to predict potential KAKAs, leveraging transfer learning on the pre-trained protein language model ProtBert. Our model, termed pKAKA, achieves an impressive AUC score of 0.9593 and outperforms the AlphaMissense benchmark in comparative testing. Systematic analysis of kinase missense mutations underscores the critical role of KAKAs in pathogenesis, with highlights including JAK2 V617F in atherosclerotic cardiovascular disease, LRRK2 G2385R in Parkinson's disease, EGFR L858R in lung adenocarcinoma, and EGFR G598V in glioma. Overall, this study significantly advances our understanding of how mutations that influence kinase activity contribute to disease mechanisms.

Hepatocellular carcinoma (HCC) is a leading cause of cancer-related death worldwide, with metastasis being the primary cause of its high mortality. The chromatin-binding protein, high mobility group nucleosome binding domain 1 (HMGN1), has been implicated in tumour progression, but its specific role and mechanism in HCC metastasis remain unclear. This study investigates the function of HMGN1 and its potential as a therapeutic target. Analysis of patient samples confirms an upregulation of HMGN1 in HCC tissues, correlating with advanced disease and poor prognosis. Functional assays demonstrate that HMGN1 promotes HCC metastasis in vitro and in vivo. Mechanistically, integrated RNA sequencing and chromatin immunoprecipitation sequencing analyses reveal that HMGN1 binds to the promoter of RAS-like proto-oncogene B (RALB) gene, recruiting the repressive histone mark H3K9me2 to epigenetically silence its transcription and drive metastasis. Therapeutically, a nanoparticle (NP) delivery system for siRNA against HMGN1 effectively silences its expression and inhibits metastasis in orthotopic liver xenograft tumour models. Our findings establish HMGN1 as a key epigenetic driver of HCC metastasis and highlight siRNA-nanoparticle targeting of HMGN1 as a promising precision therapeutic strategy.

Rice yield is fundamentally governed by source-sink dynamics, in which the efficient translocation of non-structural carbohydrates (NSC) plays a pivotal role. Our previously developed GCGT photorespiratory bypass rice, while possessing high photosynthetic capacity, exhibits disordered sugar metabolism that impedes photoassimilate translocation and leads to a reduced seed-setting rate. To tackle this bottleneck, we construct a transport-facilitating molecular module, RSS, by integrating α-amylase (OsRAmy2A), sucrose phosphate synthase (OsSPS8), and sucrose transporter (OsSUT1) genes. In field trials, RSS rice plants (in both ZH11 and GCGT backgrounds) display significant increases in seed-setting rate, harvest index (HI), and grain yield. Crucially, the RSS module redirects photoassimilate partitioning, reducing NSC accumulation in vegetative tissues while enhancing allocation to panicles. This strategy not only improves yield in wild-type plants but also effectively ameliorates the sugar metabolism defects and photoassimilate stagnation in high-photosynthetic-efficient GCGT rice, substantially restoring the seed-setting rate. Taken together, our results demonstrate that the transport-facilitating molecular module RSS can significantly improve seed-setting rate and yield in rice, offering an effective strategy to unlock yield potential for rice.

Anther development is crucial for plant sexual reproduction. However, a high-resolution, cell-type-specific transcriptomic atlas of this process is lacking for the legume crop soybean (Glycine max). Here, we construct a comprehensive transcriptional atlas of developing soybean anthers using single-nucleus RNA sequencing (snRNA-seq). We identify and characterize nine distinct cell types spanning both somatic and reproductive lineages. Our analysis reveals robust transcriptional continuity across anther developmental stages and dynamic reprogramming during key transitions. Notably, the shift from diploid meiocytes to haploid unicellular microspores is marked by the induction of previously inactive genes, despite an overall reduction in transcript abundance. Subsequently, within bicellular microspores, generative and vegetative cell lineages exhibit sharply divergent transcriptional programs: generative cells specialize in mRNA export and turnover, whereas vegetative cells up-regulate translational machinery. Evolutionary analysis further indicates that generative-cell-specific genes are subject to more relaxed purifying selection compared to those specific to vegetative cells. Functional validation using mutants generated by CRISPR/Cas9-mediated genome editing and EMS mutagenesis reveals the essential roles of OSD1A and PKSA in pollen development and fertility. This high-resolution atlas provides fundamental insights into the transcriptional regulation of soybean anther development and serves as a valuable resource for manipulating male fertility to advance hybrid breeding programs. The data are available to browse at https://databases.genedenovo.com/pollen.