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1.
Nat Immunol ; 21(3): 287-297, 2020 03.
Article in English | MEDLINE | ID: mdl-31932812

ABSTRACT

Cancer cells subvert immune surveillance through inhibition of T cell effector function. Elucidation of the mechanism of T cell dysfunction is therefore central to cancer immunotherapy. Here, we report that dual specificity phosphatase 2 (DUSP2; also known as phosphatase of activated cells 1, PAC1) acts as an immune checkpoint in T cell antitumor immunity. PAC1 is selectively upregulated in exhausted tumor-infiltrating lymphocytes and is associated with poor prognosis of patients with cancer. PAC1hi effector T cells lose their proliferative and effector capacities and convert into exhausted T cells. Deletion of PAC1 enhances immune responses and reduces cancer susceptibility in mice. Through activation of EGR1, excessive reactive oxygen species in the tumor microenvironment induce expression of PAC1, which recruits the Mi-2ß nucleosome-remodeling and histone-deacetylase complex, eventually leading to chromatin remodeling of effector T cells. Our study demonstrates that PAC1 is an epigenetic immune regulator and highlights the importance of targeting PAC1 in cancer immunotherapy.


Subject(s)
Dual Specificity Phosphatase 2/immunology , Neoplasms/immunology , T-Lymphocytes/immunology , Animals , Chromatin/genetics , Chromatin/metabolism , Dual Specificity Phosphatase 2/deficiency , Dual Specificity Phosphatase 2/genetics , Early Growth Response Protein 1/metabolism , Female , Humans , Lymphocyte Activation , Lymphocytes, Tumor-Infiltrating/immunology , Male , Mi-2 Nucleosome Remodeling and Deacetylase Complex/metabolism , Mice , Mice, Inbred C57BL , Mice, Inbred NOD , Mice, Knockout , Mice, SCID , Neoplasms/genetics , Neoplasms/metabolism , Reactive Oxygen Species/metabolism , Tumor Microenvironment/genetics , Tumor Microenvironment/immunology , Up-Regulation
2.
Plant Cell ; 36(6): 2117-2139, 2024 May 29.
Article in English | MEDLINE | ID: mdl-38345423

ABSTRACT

Plants have evolved complex mechanisms to adapt to harsh environmental conditions. Rice (Oryza sativa) is a staple food crop that is sensitive to low temperatures. However, its cold stress responses remain poorly understood, thus limiting possibilities for crop engineering to achieve greater cold tolerance. In this study, we constructed a rice pan-transcriptome and characterized its transcriptional regulatory landscape in response to cold stress. We performed Iso-Seq and RNA-Seq of 11 rice cultivars subjected to a time-course cold treatment. Our analyses revealed that alternative splicing-regulated gene expression plays a significant role in the cold stress response. Moreover, we identified CATALASE C (OsCATC) and Os03g0701200 as candidate genes for engineering enhanced cold tolerance. Importantly, we uncovered central roles for the 2 serine-arginine-rich proteins OsRS33 and OsRS2Z38 in cold tolerance. Our analysis of cold tolerance and resequencing data from a diverse collection of 165 rice cultivars suggested that OsRS2Z38 may be a key selection gene in japonica domestication for cold adaptation, associated with the adaptive evolution of rice. This study systematically investigated the distribution, dynamic changes, and regulatory mechanisms of alternative splicing in rice under cold stress. Overall, our work generates a rich resource with broad implications for understanding the genetic basis of cold response mechanisms in plants.


Subject(s)
Alternative Splicing , Gene Expression Profiling , Gene Expression Regulation, Plant , Oryza , Plant Proteins , Oryza/genetics , Oryza/physiology , Alternative Splicing/genetics , Plant Proteins/genetics , Plant Proteins/metabolism , Cold Temperature , Cold-Shock Response/genetics , Transcriptome/genetics
3.
Nature ; 592(7856): 763-767, 2021 04.
Article in English | MEDLINE | ID: mdl-33762728

ABSTRACT

Systemic insulin sensitivity shows a diurnal rhythm with a peak upon waking1,2. The molecular mechanism that underlies this temporal pattern is unclear. Here we show that the nuclear receptors REV-ERB-α and REV-ERB-ß (referred to here as 'REV-ERB') in the GABAergic (γ-aminobutyric acid-producing) neurons in the suprachiasmatic nucleus (SCN) (SCNGABA neurons) control the diurnal rhythm of insulin-mediated suppression of hepatic glucose production in mice, without affecting diurnal eating or locomotor behaviours during regular light-dark cycles. REV-ERB regulates the rhythmic expression of genes that are involved in neurotransmission in the SCN, and modulates the oscillatory firing activity of SCNGABA neurons. Chemogenetic stimulation of SCNGABA neurons at waking leads to glucose intolerance, whereas restoration of the temporal pattern of either SCNGABA neuron firing or REV-ERB expression rescues the time-dependent glucose metabolic phenotype caused by REV-ERB depletion. In individuals with diabetes, an increased level of blood glucose after waking is a defining feature of the 'extended dawn phenomenon'3,4. Patients with type 2 diabetes with the extended dawn phenomenon exhibit a differential temporal pattern of expression of REV-ERB genes compared to patients with type 2 diabetes who do not have the extended dawn phenomenon. These findings provide mechanistic insights into how the central circadian clock regulates the diurnal rhythm of hepatic insulin sensitivity, with implications for our understanding of the extended dawn phenomenon in type 2 diabetes.


Subject(s)
Circadian Rhythm , GABAergic Neurons/physiology , Insulin Resistance , Liver/physiology , Nuclear Receptor Subfamily 1, Group D, Member 1/physiology , Animals , Blood Glucose , Circadian Clocks , Diabetes Mellitus, Type 2 , Female , Glucose/metabolism , Humans , Male , Mice , Mice, Inbred C57BL , Mice, Knockout , Middle Aged , Photoperiod , Suprachiasmatic Nucleus/cytology , Synaptic Transmission
4.
Plant Cell ; 35(6): 2062-2078, 2023 05 29.
Article in English | MEDLINE | ID: mdl-36881857

ABSTRACT

Inflorescence branch number is a yield-related trait controlled by cell fate determination in meristems. Two MADS-box transcription factors (TFs)-SISTER OF TM3 (STM3) and JOINTLESS 2 (J2)-have opposing regulatory roles in inflorescence branching. However, the mechanisms underlying their regulatory functions in inflorescence determinacy remain unclear. Here, we characterized the functions of these TFs in tomato (Solanum lycopersicum) floral meristem and inflorescence meristem (IM) through chromatin immunoprecipitation and sequencing analysis of their genome-wide occupancy. STM3 and J2 activate or repress the transcription of a set of common putative target genes, respectively, through recognition and binding to CArG box motifs. FRUITFULL1 (FUL1) is a shared putative target of STM3 and J2 and these TFs antagonistically regulate FUL1 in inflorescence branching. Moreover, STM3 physically interacts with J2 to mediate its cytosolic redistribution and restricts J2 repressor activity by reducing its binding to target genes. Conversely, J2 limits STM3 regulation of target genes by transcriptional repression of the STM3 promoter and reducing STM3-binding activity. Our study thus reveals an antagonistic regulatory relationship in which STM3 and J2 control tomato IM determinacy and branch number.


Subject(s)
Solanum lycopersicum , Solanum lycopersicum/genetics , Inflorescence/genetics , Cell Differentiation , Chromatin Immunoprecipitation , Cytosol , Meristem/genetics , Gene Expression Regulation, Plant/genetics
5.
Proc Natl Acad Sci U S A ; 120(39): e2307722120, 2023 09 26.
Article in English | MEDLINE | ID: mdl-37725654

ABSTRACT

Single-cell RNA-seq (scRNA-seq) analysis of multiple samples separately can be costly and lead to batch effects. Exogenous barcodes or genome-wide RNA mutations can be used to demultiplex pooled scRNA-seq data, but they are experimentally or computationally challenging and limited in scope. Mitochondrial genomes are small but diverse, providing concise genotype information. We developed "mitoSplitter," an algorithm that demultiplexes samples using mitochondrial RNA (mtRNA) variants, and demonstrated that mtRNA variants can be used to demultiplex large-scale scRNA-seq data. Using affordable computational resources, mitoSplitter can accurately analyze 10 samples and 60,000 cells in 6 h. To avoid the batch effects from separated experiments, we applied mitoSplitter to analyze the responses of five non-small cell lung cancer cell lines to BET (Bromodomain and extraterminal) chemical degradation in a multiplexed fashion. We found the synthetic lethality of TOP2A inhibition and BET chemical degradation in BET inhibitor-resistant cells. The result indicates that mitoSplitter can accelerate the application of scRNA-seq assays in biomedical research.


Subject(s)
Carcinoma, Non-Small-Cell Lung , Lung Neoplasms , Humans , RNA, Mitochondrial , Single-Cell Gene Expression Analysis , Mitochondria/genetics
6.
Dev Biol ; 508: 123-137, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38290645

ABSTRACT

microRNAs are evolutionarily conserved non-coding RNAs that direct post-transcriptional regulation of target transcripts. In vertebrates, microRNA-1 (miR-1) is expressed in muscle and has been found to play critical regulatory roles in vertebrate angiogenesis, a process that has been proposed to be analogous to sea urchin skeletogenesis. Results indicate that both miR-1 inhibitor and miR-1 mimic-injected larvae have significantly less F-actin enriched circumpharyngeal muscle fibers and fewer gut contractions. In addition, miR-1 regulates the positioning of skeletogenic primary mesenchyme cells (PMCs) and skeletogenesis of the sea urchin embryo. Interestingly, the gain-of-function of miR-1 leads to more severe PMC patterning and skeletal branching defects than its loss-of-function. The results suggest that miR-1 directly suppresses Ets1/2, Tbr, and VegfR7 of the skeletogenic gene regulatory network, and Nodal, and Wnt1 signaling components. This study identifies potential targets of miR-1 that impacts skeletogenesis and muscle formation and contributes to a deeper understanding of miR-1's function during development.


Subject(s)
MicroRNAs , Animals , MicroRNAs/genetics , MicroRNAs/metabolism , Embryo, Nonmammalian/metabolism , Sea Urchins/genetics , Sea Urchins/metabolism , Signal Transduction/genetics , Gene Regulatory Networks , Gene Expression Regulation, Developmental/genetics , Mesoderm/metabolism
7.
J Cell Sci ; 136(5)2023 03 01.
Article in English | MEDLINE | ID: mdl-36751992

ABSTRACT

Mitosis is a fundamental and highly regulated process that acts to faithfully segregate chromosomes into two identical daughter cells. Localization of gene transcripts involved in mitosis to the mitotic spindle might be an evolutionarily conserved mechanism to ensure that mitosis occurs in a timely manner. We identified many RNA transcripts that encode proteins involved in mitosis localized at the mitotic spindles in dividing sea urchin embryos and mammalian cells. Disruption of microtubule polymerization, kinesin-1 or dynein results in lack of spindle localization of these transcripts in the sea urchin embryo. Furthermore, results indicate that the cytoplasmic polyadenylation element (CPE) within the 3'UTR of the Aurora B transcript, a recognition sequence for CPEB, is essential for RNA localization to the mitotic spindle in the sea urchin embryo. Blocking this sequence results in arrested development during early cleavage stages, suggesting that RNA localization to the mitotic spindle might be a regulatory mechanism of cell division that is important for early development.


Subject(s)
Dyneins , Kinesins , Animals , Kinesins/metabolism , Dyneins/metabolism , Spindle Apparatus/metabolism , Mitosis , RNA/metabolism , Microtubules/metabolism , Mammals/metabolism
8.
Plant Physiol ; 2024 Jun 26.
Article in English | MEDLINE | ID: mdl-38918826

ABSTRACT

Waterlogging is a serious abiotic stress that drastically decreases crop productivity by damaging the root system. Jasmonic acid (JA) inhibits waterlogging-induced adventitious root (AR) formation in cucumber (Cucumis sativus L.). However, we still lack a profound mechanistic understanding of how JA governs AR formation under waterlogging stress. JAZ (JASMONATE ZIM-DOMAIN) proteins are responsible for repressing JA signaling in a transcriptional manner. In this study, we showed that overexpressing CsJAZ8 inhibited the formation of ARs triggered by waterlogging. Molecular analyses revealed that CsJAZ8 inhibited the activation of the R2R3-MYB transcription factor CsMYB6 via direct interaction. Additionally, silencing of CsMYB6 negatively impacted AR formation under waterlogging stress, as CsMYB6 could directly bind to the promoters of 1-aminocyclopropane-1-carboxylate oxidase2 gene CsACO2 and gibberellin 20-oxidases gene CsGA20ox2, facilitating the transcription of these genes. The overexpression of CsACO2 and CsGA20ox2 led to increased levels of ethylene and gibberellin, which facilitated AR formation under waterlogging conditions. On the contrary, silencing these genes resulted in contrasting phenotypes of AR formation. These results highlight that the transcriptional cascade of CsJAZ8 and CsMYB6 plays a critical role in regulating hormonal-mediated cucumber waterlogging-triggered AR formation by inhibiting ethylene and gibberellin accumulation. We anticipate that our findings will provide insights into the molecular mechanisms that drive the emergence of AR in cucumber plants under waterlogging stress.

9.
Plant Physiol ; 194(4): 2491-2510, 2024 Mar 29.
Article in English | MEDLINE | ID: mdl-38039148

ABSTRACT

Passion fruit (Passiflora edulis) possesses a complex aroma and is widely grown in tropical and subtropical areas. Here, we conducted the de novo assembly, annotation, and comparison of PPF (P. edulis Sims) and YPF (P. edulis f. flavicarpa) reference genomes using PacBio, Illumina, and Hi-C technologies. Notably, we discovered evidence of recent whole-genome duplication events in P. edulis genomes. Comparative analysis revealed 7.6∼8.1 million single nucleotide polymorphisms, 1 million insertions/deletions, and over 142 Mb presence/absence variations among different P. edulis genomes. During the ripening of yellow passion fruit, metabolites related to flavor, aroma, and color were substantially accumulated or changed. Through joint analysis of genomic variations, differentially expressed genes, and accumulated metabolites, we explored candidate genes associated with flavor, aroma, and color distinctions. Flavonoid biosynthesis pathways, anthocyanin biosynthesis pathways, and related metabolites are pivotal factors affecting the coloration of passion fruit, and terpenoid metabolites accumulated more in PPF. Finally, by heterologous expression in yeast (Saccharomyces cerevisiae), we functionally characterized 12 terpene synthases. Our findings revealed that certain TPS homologs in both YPF and PPF varieties produce identical terpene products, while others yield distinct compounds or even lose their functionality. These discoveries revealed the genetic and metabolic basis of unique characteristics in aroma and flavor between the 2 passion fruit varieties. This study provides resources for better understanding the genome architecture and accelerating genetic improvement of passion fruits.


Subject(s)
Fruit , Passiflora , Fruit/genetics , Odorants , Passiflora/genetics , Passiflora/metabolism , Multiomics , Terpenes/metabolism
10.
Circ Res ; 133(1): e1-e16, 2023 06 23.
Article in English | MEDLINE | ID: mdl-37154033

ABSTRACT

BACKGROUND: Atrial fibrillation (AF), the most common arrhythmia, is associated with the downregulation of FKBP5 (encoding FKBP5 [FK506 binding protein 5]). However, the function of FKBP5 in the heart remains unknown. Here, we elucidate the consequences of cardiomyocyte-restricted loss of FKBP5 on cardiac function and AF development and study the underlying mechanisms. METHODS: Right atrial samples from patients with AF were used to assess the protein levels of FKBP5. A cardiomyocyte-specific FKBP5 knockdown mouse model was established by crossbreeding Fkbp5flox/flox mice with Myh6MerCreMer/+ mice. Cardiac function and AF inducibility were assessed by echocardiography and programmed intracardiac stimulation. Histology, optical mapping, cellular electrophysiology, and biochemistry were employed to elucidate the proarrhythmic mechanisms due to loss of cardiomyocyte FKBP5. RESULTS: FKBP5 protein levels were lower in the atrial lysates of patients with paroxysmal AF or long-lasting persistent (chronic) AF. Cardiomyocyte-specific knockdown mice exhibited increased AF inducibility and duration compared with control mice. Enhanced AF susceptibility in cardiomyocyte-specific knockdown mice was associated with the development of action potential alternans and spontaneous Ca2+ waves, and increased protein levels and activity of the NCX1 (Na+/Ca2+-exchanger 1), mimicking the cellular phenotype of chronic AF patients. FKBP5-deficiency enhanced transcription of Slc8a1 (encoding NCX1) via transcription factor hypoxia-inducible factor 1α. In vitro studies revealed that FKBP5 negatively modulated the protein levels of hypoxia-inducible factor 1α by competitively interacting with heat-shock protein 90. Injections of the heat-shock protein 90 inhibitor 17-AAG normalized protein levels of hypoxia-inducible factor 1α and NCX1 and reduced AF susceptibility in cardiomyocyte-specific knockdown mice. Furthermore, the atrial cardiomyocyte-selective knockdown of FKBP5 was sufficient to enhance AF arrhythmogenesis. CONCLUSIONS: This is the first study to demonstrate a role for the FKBP5-deficiency in atrial arrhythmogenesis and to establish FKBP5 as a negative regulator of hypoxia-inducible factor 1α in cardiomyocytes. Our results identify a potential molecular mechanism for the proarrhythmic NCX1 upregulation in chronic AF patients.


Subject(s)
Atrial Fibrillation , Mice , Animals , Atrial Fibrillation/metabolism , Down-Regulation , Myocytes, Cardiac/metabolism , Hypoxia/metabolism , Heat-Shock Proteins/metabolism
11.
Proc Natl Acad Sci U S A ; 119(41): e2211538119, 2022 10 11.
Article in English | MEDLINE | ID: mdl-36191233

ABSTRACT

Efficient molecular selection is a prerequisite for generating molecular tools used in diagnosis, pathology, vaccinology, and therapeutics. Selection efficiency is thermodynamically highly dependent on the dissociation equilibrium that can be reached in a single round. Extreme shifting of equilibrium towards dissociation favors the retention of high-affinity ligands over those with lower affinity, thus improving the selection efficiency. We propose to synergize dual effects by deterministic lateral-displacement microfluidics, including the collision-based force effect and the two-dimensional (2D) separation-based concentration effect, to greatly shift the equilibrium. Compared with previous approaches, this system can remove more low- or moderate-affinity ligands and maintain most high-affinity ligands, thereby improving affinity discrimination in selection. This strategy is demonstrated on phage display in both experiment and simulation, and two peptides against tumor markers ephrin type-A receptor 2 (EphA2) and CD71 were obtained with high affinity and specificity within a single round of selection, which offers a promising direction for discovery of robust binding ligands for a wide range of biomedical applications.


Subject(s)
Microfluidics , Peptides , Biomarkers, Tumor , Ephrins , Ligands , Peptides/chemistry
12.
Proc Natl Acad Sci U S A ; 119(5)2022 02 01.
Article in English | MEDLINE | ID: mdl-35086932

ABSTRACT

Single-cell RNA-sequencing (scRNA-seq) has become a powerful tool for biomedical research by providing a variety of valuable information with the advancement of computational tools. Lineage analysis based on scRNA-seq provides key insights into the fate of individual cells in various systems. However, such analysis is limited by several technical challenges. On top of the considerable computational expertise and resources, these analyses also require specific types of matching data such as exogenous barcode information or bulk assay for transposase-accessible chromatin with high throughput sequencing (ATAC-seq) data. To overcome these technical challenges, we developed a user-friendly computational algorithm called "LINEAGE" (label-free identification of endogenous informative single-cell mitochondrial RNA mutation for lineage analysis). Aiming to screen out endogenous markers of lineage located on mitochondrial reads from label-free scRNA-seq data to conduct lineage inference, LINEAGE integrates a marker selection strategy by feature subspace separation and de novo "low cross-entropy subspaces" identification. In this process, the mutation type and subspace-subspace "cross-entropy" of features were both taken into consideration. LINEAGE outperformed three other methods, which were designed for similar tasks as testified with two standard datasets in terms of biological accuracy and computational efficiency. Applied on a label-free scRNA-seq dataset of BRAF-mutated cancer cells, LINEAGE also revealed genes that contribute to BRAF inhibitor resistance. LINEAGE removes most of the technical hurdles of lineage analysis, which will remarkably accelerate the discovery of the important genes or cell-lineage clusters from scRNA-seq data.


Subject(s)
Cell Lineage/genetics , RNA, Mitochondrial/genetics , Sequence Analysis, RNA/methods , Algorithms , Animals , Cluster Analysis , Gene Expression Profiling/methods , High-Throughput Nucleotide Sequencing/methods , Humans , Mutation/genetics , RNA/analysis , Single-Cell Analysis/methods , Exome Sequencing/methods
13.
J Allergy Clin Immunol ; 153(4): 1025-1039, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38072196

ABSTRACT

BACKGROUND: Ectopic lymphoid tissues (eLTs) and associated follicular helper T (TFH) cells contribute to local immunoglobulin hyperproduction in nasal polyps (NPs). Follicular regulatory T (TFR) cells in secondary lymphoid organs counteract TFH cells and suppress immunoglobulin production; however, the presence and function of TFR cells in eLTs in peripheral diseased tissues remain poorly understood. OBJECTIVE: We sought to investigate the presence, phenotype, and function of TFR cells in NPs. METHODS: The presence, abundance, and phenotype of TFR cells in NPs were examined using single-cell RNA sequencing, immunofluorescence staining, and flow cytometry. Sorted polyp and circulating T-cell subsets were cocultured with autologous circulating naïve B cells, and cytokine and immunoglobulin production were measured by ELISA. RESULTS: TFR cells were primarily localized within eLTs in NPs. TFR cell frequency and TFR cell/TFH cell ratio were decreased in NPs with eLTs compared with NPs without eLTs and control inferior turbinate tissues. TFR cells displayed an overlapping phenotype with TFH cells and FOXP3+ regulatory T cells in NPs. Polyp TFR cells had reduced CTLA-4 expression and decreased capacity to inhibit TFH cell-induced immunoglobulin production compared with their counterpart in blood and tonsils. Blocking CTLA-4 abolished the suppressive effect of TFR cells. Lower vitamin D receptor expression was observed on polyp TFR cells compared with TFR cells in blood and tonsils. Vitamin D treatment upregulated CTLA-4 expression on polyp TFR cells and restored their suppressive function in vitro. CONCLUSIONS: Polyp TFR cells in eLTs have decreased CLTA-4 and vitamin D receptor expression and impaired capacity to suppress TFH cell-induced immunoglobulin production, which can be reversed by vitamin D treatment in vitro.


Subject(s)
Nasal Polyps , Tertiary Lymphoid Structures , Humans , T-Lymphocytes, Regulatory/pathology , T-Lymphocytes, Helper-Inducer/pathology , CTLA-4 Antigen/metabolism , Receptors, Calcitriol/metabolism , Nasal Polyps/pathology , Tertiary Lymphoid Structures/pathology , Immunoglobulins/metabolism , Vitamin D/metabolism
14.
Nano Lett ; 24(13): 4012-4019, 2024 Apr 03.
Article in English | MEDLINE | ID: mdl-38527220

ABSTRACT

The measurement of in-plane mechanical properties, such as Young's modulus and strength, of thin and stretchable materials has long been a challenge. Existing measurements, including wrinkle instability and nano indentation, are either indirect or destructive, and are inapplicable to meshes or porous materials, while the conventional tension test fails to measure the mechanical properties of nanoscale films. Here, we report a technique to test thin and stretchable films by loading a thin film afloat via differential surface tension and recording its deformation. We have demonstrated the method by measuring the Young's moduli of homogeneous films of soft materials including polydimethylsiloxane and Ecoflex and verified the results with known values. We further measured the strain distributions of meshes, both isotropic and anisotropic, which were otherwise nearly impossible to measure. The method proposed herein is expected to be generally applicable to many material systems that are thin, stretchable, and water-insoluble.

15.
Dev Biol ; 502: 50-62, 2023 10.
Article in English | MEDLINE | ID: mdl-37419400

ABSTRACT

MicroRNAs regulate gene expression post-transcriptionally by destabilizing and/or inhibiting translation of target mRNAs in animal cells. MicroRNA-124 (miR-124) has been examined mostly in the context of neurogenesis. This study discovers a novel role of miR-124 in regulating mesodermal cell differentiation in the sea urchin embryo. The expression of miR-124 is first detectable at 12hours post fertilization at the early blastula stage, during endomesodermal specification. Mesodermally-derived immune cells come from the same progenitor cells that give rise to blastocoelar cells (BCs) and pigment cells (PCs) that must make a binary fate decision. We determined that miR-124 directly represses Nodal and Notch to regulate BC and PC differentiation. miR-124 inhibition does not impact the dorsal-ventral axis formation, but result in a significant increase in number of cells expressing BC-specific transcription factors (TFs) and a concurrent reduction of differentiated PCs. In general, removing miR-124's suppression of Nodal phenocopies miR124 inhibition. Interestingly, removing miR-124's suppression of Notch leads to an increased number of both BCs and PCs, with a subset of hybrid cells that express both BC- and PC-specific TFs in the larvae. Removal of miR-124's suppression of Notch not only affects differentiation of both BCs and PCs, but also induces cell proliferation of these cells during the first wave of Notch signaling. This study demonstrates that post-transcriptional regulation by miR-124 impacts differentiation of BCs and PCs by regulating the Nodal and Notch signaling pathways.


Subject(s)
MicroRNAs , Receptors, Notch , Animals , Receptors, Notch/genetics , Receptors, Notch/metabolism , MicroRNAs/genetics , MicroRNAs/metabolism , Cell Differentiation/genetics , Signal Transduction/genetics , Gene Expression Regulation , Transforming Growth Factor beta/metabolism
16.
Plant J ; 113(6): 1259-1277, 2023 03.
Article in English | MEDLINE | ID: mdl-36648165

ABSTRACT

Auxin is indispensable to the fertilization-induced coordinated development of the embryo, endosperm, and seed coat. However, little attention has been given to the distribution pattern, maintenance mechanism, and function of auxin throughout the process of seed development. In the present study, we found that auxin response signals display a dynamic distribution pattern during Arabidopsis seed development. Shortly after fertilization, strong auxin response signals were observed at the funiculus, chalaza, and micropylar integument where the embryo attaches. Later, additional signals appeared at the middle layer of the inner integument (ii1') above the chalaza and the whole inner layer of the outer integument (oi1). These signals peaked when the seed was mature, then declined upon desiccation and disappeared in the dried seed. Auxin biosynthesis genes, including ASB1, TAA1, YUC1, YUC4, YUC8, and YUC9, contributed to the accumulation of auxin in the funiculus and seed coat. Auxin efflux carrier PIN3 and influx carrier AUX1 also contributed to the polar auxin distribution in the seed coat. PIN3 was expressed in the ii1 (innermost layer of the inner integument) and oi1 layers of the integument and showed polar localization. AUX1 was expressed in both layers of the outer integument and the endosperm and displayed a uniform localization. Further research demonstrated that the accumulation of auxin in the seed coat regulates seed size. Transgenic plants that specifically express the YUC8 gene in the oi2 or ii1 seed coat produced larger seeds. These results provide useful tools for cultivating high-yielding crops.


Subject(s)
Arabidopsis Proteins , Arabidopsis , Arabidopsis/metabolism , Arabidopsis Proteins/genetics , Arabidopsis Proteins/metabolism , Indoleacetic Acids , Seeds/metabolism , Endosperm/genetics , Endosperm/metabolism , Gene Expression Regulation, Plant
17.
BMC Genomics ; 25(1): 712, 2024 Jul 24.
Article in English | MEDLINE | ID: mdl-39044139

ABSTRACT

BACKGROUND: Yaks are a vital livestock in the Qinghai-Tibetan Plateau area for providing food products, maintaining sustainable ecosystems, and promoting cultural heritage. Because of uncontrolled mating, it is impossible to estimate inbreeding level of yak populations using the pedigree-based approaches. With the aims to accurately evaluate inbreeding level of two Chinese yak populations (Maiwa and Jiulong), we obtained genome-wide single nucleotide polymorphisms (SNPs) by DNA sequencing and calculated five SNP-by-SNP estimators ([Formula: see text], [Formula: see text], [Formula: see text], [Formula: see text], and [Formula: see text]), as well as two segment-based estimators of runs of homozygosity (ROH, [Formula: see text]) and homozygous-by-descent (HBD, [Formula: see text]). Functional implications were analyzed for the positional candidate genes located within the related genomic regions. RESULTS: A total of 151,675 and 190,955 high-quality SNPs were obtained from 71 Maiwa and 30 Jiulong yaks, respectively. Jiulong had greater genetic diversity than Maiwa in terms of allele frequency and nucleotide diversity. The two populations could be genetically distinguished by principal component analysis, with the mean differentiation index (Fst) of 0.0054. The greater genomic inbreeding levels of Maiwa yaks were consistently supported by all five SNP-by-SNP estimators. Based on simple proportion of homozygous SNPs ([Formula: see text]), a lower inbreeding level was indicated by three successfully sequenced old leather samples that may represent historical Maiwa yaks about five generations ago. There were 3304 ROH detected among all samples, with mean and median length of 1.97 Mb and 1.0 Mb, respectively. A total of 94 HBD segments were found among all samples, whereas 92 of them belonged to the shortest class with the mean length of 10.9 Kb. Based on the estimates of [Formula: see text] and [Formula: see text], however, there was no difference in inbreeding level between Maiwa and Jiulong yaks. Within the genomic regions with the significant Fst or enriched by ROH, we found several candidate genes and pathways that have been reported to be related to diverse production traits in farm animals. CONCLUSIONS: We successfully evaluated the genomic inbreeding level of two Chinese yak populations. Although different estimators resulted in inconsistent conclusions on their genomic inbreeding levels, our results may be helpful to implement the genetic conservation and utilization programs for the two yak populations.


Subject(s)
Genomics , Inbreeding , Polymorphism, Single Nucleotide , Animals , Cattle/genetics , Genomics/methods , China , Gene Frequency , Genetics, Population , Homozygote , Genome
18.
Mol Biol Evol ; 40(5)2023 05 02.
Article in English | MEDLINE | ID: mdl-37134013

ABSTRACT

HIV-1 is a highly host-specific retrovirus that infects humans but not most nonhuman primates. Thus, the lack of a suitable primate model that can be directly infected with HIV-1 hinders HIV-1/AIDS research. In the previous study, we have found that the northern pig-tailed macaques (NPMs) are susceptible to HIV-1 infection but show a nonpathogenic state. In this study, to understand this macaque-HIV-1 interaction, we assembled a de novo genome and longitudinal transcriptome for this species during the course of HIV-1 infection. Using comparative genomic analysis, a positively selected gene, Toll-like receptor 8, was identified with a weak ability to induce an inflammatory response in this macaque. In addition, an interferon-stimulated gene, interferon alpha inducible protein 27, was upregulated in acute HIV-1 infection and acquired an enhanced ability to inhibit HIV-1 replication compared with its human ortholog. These findings coincide with the observation of persistently downregulated immune activation and low viral replication and can partially explain the AIDS-free state in this macaque following HIV-1 infection. This study identified a number of unexplored host genes that may hamper HIV-1 replication and pathogenicity in NPMs and provided new insights into the host defense mechanisms in cross-species infection of HIV-1. This work will facilitate the adoption of NPM as a feasible animal model for HIV-1/AIDS research.


Subject(s)
HIV Infections , HIV-1 , Simian Immunodeficiency Virus , Animals , Humans , Macaca nemestrina , HIV-1/genetics , Genomics , Simian Immunodeficiency Virus/genetics
19.
Plant Cell Physiol ; 2024 Jul 10.
Article in English | MEDLINE | ID: mdl-38985662

ABSTRACT

To analyze the gene involved in orchid floral development, a HD-Zip II gene PaHAT14, which specifically and highly expressed in perianth during early flower development was identified from Phalaenopsis. Transgenic Arabidopsis plants expressing 35S::PaHAT14 and 35S::PaHAT14+SRDX (fused with the repressor motif SRDX) exhibited similar altered phenotypes, including small leaves, early flowering, and bending petals with increased cuticle production. This suggests that PaHAT14 acts as a repressor. In contrast, transgenic Arabidopsis plants expressing 35S::PaHAT14+VP16 (fused with the activation domain VP16) exhibited curled leaves, late flowering, and folded petals with decreased cuticle production within hardly opened flowers. Additionally, the expression of the ERF gene DEWAX2, which negatively regulates cuticular wax biosynthesis, was down-regulated in 35S::PaHAT14 and 35S::PaHAT14+SRDX transgenic Arabidopsis, while it was up-regulated in 35S::PaHAT14+VP16 transgenic Arabidopsis. Furthermore, transient overexpression of PaHAT14 in Phalaenopsis petal/sepal increased cuticle deposition due to the down-regulation of PaERF105, a Phalaenopsis DEWAX2 orthologue. On the other hand, transient overexpression of PaERF105 decreased cuticle deposition, whereas cuticle deposition increased and the rate of epidermal water loss was reduced in PaERF105 VIGS Phalaenopsis flowers. Moreover, ectopic expression of PaERF105 not only produced phenotypes similar to those in 35S::PaHAT14+VP16 Arabidopsis but also compensated for the altered phenotypes observed in 35S::PaHAT14 and 35S::PaHAT14+SRDX Arabidopsis. These results suggest that PaHAT14 promotes cuticle deposition by negatively regulating downstream gene PaERF105 in orchid flowers.

20.
Br J Haematol ; 204(3): 1082-1085, 2024 Mar.
Article in English | MEDLINE | ID: mdl-37932927

ABSTRACT

Currently, there is no effective treatment for refractory/relapsed (R/R) autoimmune haemolytic anaemia (AIHA), associated with poor quality of life. Bruton tyrosine kinase inhibitors have begun to be used in some autoimmune diseases. We initiated the clinical trial of orelabrutinib treatment on R/R AIHA/Evans Syndrome, which is in progress. The preliminary results showed that nine of the 12 enrolled patients responded to orelabrutinib treatment. Here, we reported three cases who have completed the treatment and were followed up for 6 months, achieving complete or partial remission. Orelabrutinib is expected to become a new second-line treatment for R/R AIHA/Evans syndrome.


Subject(s)
Anemia, Hemolytic, Autoimmune , Piperidines , Pyridines , Thrombocytopenia , Humans , Anemia, Hemolytic, Autoimmune/therapy , Pilot Projects , Quality of Life
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