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1.
Biomimetics (Basel) ; 9(4)2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38667238

RESUMO

The osteoblastic differentiation of bone marrow stromal cells (bMSCs), critical to the osseointegration of titanium implants, is enhanced on titanium surfaces with biomimetic topography, and this is further enhanced when the surfaces are hydrophilic. This is a result of changing the surface free energy to change protein adsorption, improving cell attachment and differentiation, and improving bone-to-implant contact in patients. In this study, we examined different methods of plasma treatment, a well-accepted method of increasing hydrophilicity, and evaluated changes in surface properties as well as the response of bMSCs in vitro. Commercially pure Ti and titanium-aluminum-vanadium (Ti6Al4V) disks were sand-blasted and acid-etched to impart microscale and nanoscale roughness, followed by treatment with various post-processing surface modification methods, including ultraviolet light (UV), dielectric barrier discharge (DBD)-generated plasma, and plasma treatment under an argon or oxygen atmosphere. Surface wettability was based on a sessile water drop measurement of contact angle; the elemental composition was analyzed using XPS, and changes in topography were characterized using scanning electron microscopy (SEM) and confocal imaging. The cell response was evaluated using bMSCs; outcome measures included the production of osteogenic markers, paracrine signaling factors, and immunomodulatory cytokines. All plasma treatments were effective in inducing superhydrophilic surfaces. Small but significant increases in surface roughness were observed following UV, DBD and argon plasma treatment. No other modifications to surface topography were noted. However, the relative composition of Ti, O, and C varied with the treatment method. The cell response to these hydrophilic surfaces depended on the plasma treatment method used. DBD plasma treatment significantly enhanced the osteogenic response of the bMSCs. In contrast, the bMSC response to argon plasma-treated surfaces was varied, with an increase in OPG production but a decrease in OCN production. These results indicate that post-packaging methods that increased hydrophilicity as measured by contact angle did not change the surface free energy in the same way, and accordingly, cells responded differently. Wettability and surface chemistry alone are not enough to declare whether an implant has an improved osteogenic effect and do not fully explain how surface free energy affects cell response.

2.
Science ; 384(6691): eabo7027, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38574142

RESUMO

Macrophages are functionally heterogeneous cells essential for apoptotic cell clearance. Apoptotic cells are defined by homogeneous characteristics, ignoring their original cell lineage identity. We found that in an interleukin-4 (IL-4)-enriched environment, the sensing of apoptotic neutrophils by macrophages triggered their tissue remodeling signature. Engulfment of apoptotic hepatocytes promoted a tolerogenic phenotype, whereas phagocytosis of T cells had little effect on IL-4-induced gene expression. In a mouse model of parasite-induced pathology, the transfer of macrophages conditioned with IL-4 and apoptotic neutrophils promoted parasitic egg clearance. Knockout of phagocytic receptors required for the uptake of apoptotic neutrophils and partially T cells, but not hepatocytes, exacerbated helminth infection. These findings suggest that the identity of apoptotic cells may contribute to the development of distinct IL-4-driven immune programs in macrophages.


Assuntos
Apoptose , Interleucina-4 , Macrófagos , Fagocitose , Esquistossomose mansoni , Animais , Camundongos , Apoptose/imunologia , Interleucina-4/genética , Interleucina-4/metabolismo , Macrófagos/imunologia , Camundongos Knockout , Neutrófilos/imunologia , Fagocitose/imunologia , Hepatócitos/imunologia , Esquistossomose mansoni/genética , Esquistossomose mansoni/imunologia
3.
Ann Biomed Eng ; 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38517621

RESUMO

Osseointegration is a complex biological cascade that regulates bone regeneration after implant placement. Implants possessing complex multiscale surface topographies augment this regenerative process through the regulation of bone marrow stromal cells (MSCs) that are in contact with the implant surface. One pathway regulating osteoblastic differentiation is Wnt signaling, and upregulation of non-canonical Wnts increases differentiation of MSCs on these titanium substrates. Wnt16 is a non-canonical Wnt shown to regulate bone morphology in mouse models. This study evaluated the role of Wnt16 during surface-mediated osteoblastic differentiation of MSCs in vitro and osseointegration in vivo. MSCs were cultured on Ti substrates with different surface properties and non-canonical Wnt expression was determined. Subsequently, MSCs were cultured on Ti substrates +/-Wnt16 (100 ng/mL) and anti-Wnt16 antibodies (2 µg/mL). Wnt16 expression was increased in cells grown on microrough surfaces that were processed to be hydrophilic and have nanoscale roughness. However, treatment MSCs on these surfaces with exogenous rhWnt16b increased total DNA content and osteoprotegerin production, but reduced osteoblastic differentiation and production of local factors necessary for osteogenesis. Addition of anti-Wnt16 antibodies blocked the inhibitor effects of Wnt16. The response to Wnt16 was likely independent of other osteogenic pathways like Wnt11-Wnt5a signaling and semaphorin 3a signaling. We used an established rat model of cortical and trabecular femoral bone impairment following botox injections (2 injections of 8 units/leg each, starting and maintenance doses) to assess Wnt16 effects on whole bone morphology and implant osseointegration. Wnt16 injections did not alter whole bone morphology significantly (BV/TV, cortical thickness, restoration of trabecular bone) but were effective at increasing cortical bone-to-implant contact during impaired osseointegration in the botox model. The mechanical quality of the increased bone was not sufficient to rescue the deleterious effects of botox. Clinically, these results are important to understand the interaction of cortical and trabecular bone during implant integration. They suggest a role for Wnt16 in modulating bone remodeling by reducing osteoclastic activity. Targeted strategies to temporally regulate Wnt16 after implant placement could be used to improve osseointegration by increasing the net pool of osteoprogenitor cells.

4.
Nat Commun ; 15(1): 1113, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38326330

RESUMO

Site-specific recombinases such as the Cre-LoxP system are routinely used for genome engineering in both prokaryotes and eukaryotes. Importantly, recombinases complement the CRISPR-Cas toolbox and provide the additional benefit of high-efficiency DNA editing without generating toxic DNA double-strand breaks, allowing multiple recombination events at the same time. However, only a handful of independent, orthogonal recombination systems are available, limiting their use in more complex applications that require multiple specific recombination events, such as metabolic engineering and genetic circuits. To address this shortcoming, we develop 63 symmetrical LoxP variants and test 1192 pairwise combinations to determine their cross-reactivity and specificity upon Cre activation. Ultimately, we establish a set of 16 orthogonal LoxPsym variants and demonstrate their use for multiplexed genome engineering in both prokaryotes (E. coli) and eukaryotes (S. cerevisiae and Z. mays). Together, this work yields a significant expansion of the Cre-LoxP toolbox for genome editing, metabolic engineering and other controlled recombination events, and provides insights into the Cre-LoxP recombination process.


Assuntos
Integrases , Recombinação Genética , Integrases/genética , Integrases/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Recombinases/metabolismo , DNA/metabolismo
5.
Eur J Immunol ; 54(2): e2350434, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37971166

RESUMO

The initiation of tissue remodeling following damage is a critical step in preventing the development of immune-mediated diseases. Several factors contribute to mucosal healing, leading to innovative therapeutic approaches for managing intestinal disorders. However, uncovering alternative targets and gaining mechanistic insights are imperative to enhance therapy efficacy and broaden its applicability across different intestinal diseases. Here we demonstrate that Nmes1, encoding for Normal Mucosa of Esophagus-Specific gene 1, also known as Aa467197, is a novel regulator of mucosal healing. Nmes1 influences the macrophage response to the tissue remodeling cytokine IL-4 in vitro. In addition, using two murine models of intestinal damage, each characterized by a type 2-dominated environment with contrasting functions, the ablation of Nmes1 results in decreased intestinal regeneration during the recovery phase of colitis, while enhancing parasitic egg clearance and reducing fibrosis during the advanced stages of Schistosoma mansoni infection. These outcomes are associated with alterations in CX3CR1+ macrophages, cells known for their wound-healing potential in the inflamed colon, hence promising candidates for cell therapies. All in all, our data indicate Nmes1 as a novel contributor to mucosal healing, setting the basis for further investigation into its potential as a new target for the treatment of colon-associated inflammation.


Assuntos
Colite , Mucosa Intestinal , Animais , Camundongos , Colite/tratamento farmacológico , Citocinas , Intestinos , Cicatrização
6.
J Physiol ; 602(1): 153-181, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37987552

RESUMO

The whisker system is widely used as a model system for understanding sensorimotor integration. Purkinje cells in the crus regions of the cerebellum have been reported to linearly encode whisker midpoint, but it is unknown whether the paramedian and simplex lobules as well as their target neurons in the cerebellar nuclei also encode whisker kinematics and if so which ones. Elucidating how these kinematics are represented throughout the cerebellar hemisphere is essential for understanding how the cerebellum coordinates multiple sensorimotor modalities. Exploring the cerebellar hemisphere of mice using optogenetic stimulation, we found that whisker movements can be elicited by stimulation of Purkinje cells in not only crus1 and crus2, but also in the paramedian lobule and lobule simplex; activation of cells in the medial paramedian lobule had on average the shortest latency, whereas that of cells in lobule simplex elicited similar kinematics as those in crus1 and crus2. During spontaneous whisking behaviour, simple spike activity correlated in general better with velocity than position of the whiskers, but it varied between protraction and retraction as well as per lobule. The cerebellar nuclei neurons targeted by the Purkinje cells showed similar activity patterns characterized by a wide variety of kinematic signals, yet with a dominance for velocity. Taken together, our data indicate that whisker movements are much more prominently and diversely represented in the cerebellar cortex and nuclei than assumed, highlighting the rich repertoire of cerebellar control in the kinematics of movements that can be engaged during coordination. KEY POINTS: Excitation of Purkinje cells throughout the cerebellar hemispheres induces whisker movement, with the shortest latency and longest duration within the paramedian lobe. Purkinje cells have differential encoding for the fast and slow components of whisking. Purkinje cells encode not only the position but also the velocity of whiskers. Purkinje cells with high sensitivity for whisker velocity are preferentially located in the medial part of lobule simplex, crus1 and lateral paramedian. In the downstream cerebellar nuclei, neurons with high sensitivity for whisker velocity are located at the intersection between the medial and interposed nucleus.


Assuntos
Cerebelo , Vibrissas , Camundongos , Animais , Vibrissas/fisiologia , Fenômenos Biomecânicos , Cerebelo/fisiologia , Células de Purkinje/fisiologia , Córtex Cerebelar
7.
New Phytol ; 241(2): 687-702, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37950543

RESUMO

Hypocotyl elongation is controlled by several signals and is a major characteristic of plants growing in darkness or under warm temperature. While already several molecular mechanisms associated with this process are known, protein degradation and associated E3 ligases have hardly been studied in the context of warm temperature. In a time-course phosphoproteome analysis on Arabidopsis seedlings exposed to control or warm ambient temperature, we observed reduced levels of diverse proteins over time, which could be due to transcription, translation, and/or degradation. In addition, we observed differential phosphorylation of the LRR F-box protein SLOMO MOTION (SLOMO) at two serine residues. We demonstrate that SLOMO is a negative regulator of hypocotyl growth, also under warm temperature conditions, and protein-protein interaction studies revealed possible interactors of SLOMO, such as MKK5, DWF1, and NCED4. We identified DWF1 as a likely SLOMO substrate and a regulator of warm temperature-mediated hypocotyl growth. We propose that warm temperature-mediated regulation of SLOMO activity controls the abundance of hypocotyl growth regulators, such as DWF1, through ubiquitin-mediated degradation.


Assuntos
Proteínas de Arabidopsis , Arabidopsis , Proteínas F-Box , Arabidopsis/metabolismo , Hipocótilo/metabolismo , Proteínas de Arabidopsis/metabolismo , Temperatura , Proteínas F-Box/metabolismo , Regulação da Expressão Gênica de Plantas
9.
Nat Rev Neurol ; 19(11): 688-709, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37857843

RESUMO

Malaria, the most prevalent mosquito-borne infectious disease worldwide, has accompanied humanity for millennia and remains an important public health issue despite advances in its prevention and treatment. Most infections are asymptomatic, but a small percentage of individuals with a heavy parasite burden develop severe malaria, a group of clinical syndromes attributable to organ dysfunction. Cerebral malaria is an infrequent but life-threatening complication of severe malaria that presents as an acute cerebrovascular encephalopathy characterized by unarousable coma. Despite effective antiparasite drug treatment, 20% of patients with cerebral malaria die from this disease, and many survivors of cerebral malaria have neurocognitive impairment. Thus, an important unmet clinical need is to rapidly identify people with malaria who are at risk of developing cerebral malaria and to develop preventive, adjunctive and neuroprotective treatments for cerebral malaria. This Review describes important advances in the understanding of cerebral malaria over the past two decades and discusses how these mechanistic insights could be translated into new therapies.


Assuntos
Encefalopatias , Malária Cerebral , Animais , Humanos , Malária Cerebral/complicações , Malária Cerebral/tratamento farmacológico , Coma
10.
iScience ; 26(7): 107119, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37534175

RESUMO

Plasmodium falciparum, a human malaria parasite, develops in red blood cells (RBCs), which represent approximately 70% of all human blood cells. Additionally, RBC-derived extracellular vesicles (RBC-EVs) represent 7.3% of the total EV population. The roles of microRNAs (miRNAs) in the consequences of P. falciparum infection are unclear. Here, we analyzed the miRNA profiles of non-infected human RBCs (niRBCs), ring-infected RBCs (riRBCs), and trophozoite-infected RBCs (trRBCs), as well as those of EVs secreted from these cells. Hsa-miR-451a was the most abundant miRNA in all RBC and RBC-EV populations, but its expression level was not affected by P. falciparum infection. Overall, the miRNA profiles of RBCs and their EVs were altered significantly after infection. Most of the differentially expressed miRNAs were shared between RBCs and their EVs. A target prediction analysis of the miRNAs revealed the possible identity of the genes targeted by these miRNAs (CXCL10, OAS1, IL7, and CCL5) involved in immunomodulation.

11.
Front Plant Sci ; 14: 1200253, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37426959

RESUMO

Industrial chicory (Cichorium intybus var. sativum) and witloof (C. intybus var. foliosum) are crops with an important economic value, mainly cultivated for inulin production and as a leafy vegetable, respectively. Both crops are rich in nutritionally relevant specialized metabolites with beneficial effects for human health. However, their bitter taste, caused by the sesquiterpene lactones (SLs) produced in leaves and taproot, limits wider applications in the food industry. Changing the bitterness would thus create new opportunities with a great economic impact. Known genes encoding enzymes involved in the SL biosynthetic pathway are GERMACRENE A SYNTHASE (GAS), GERMACRENE A OXIDASE (GAO), COSTUNOLIDE SYNTHASE (COS) and KAUNIOLIDE SYNTHASE (KLS). In this study, we integrated genome and transcriptome mining to further unravel SL biosynthesis. We found that C. intybus SL biosynthesis is controlled by the phytohormone methyl jasmonate (MeJA). Gene family annotation and MeJA inducibility enabled the pinpointing of candidate genes related with the SL biosynthetic pathway. We specifically focused on members of subclade CYP71 of the cytochrome P450 family. We verified the biochemical activity of 14 C. intybus CYP71 enzymes transiently produced in Nicotiana benthamiana and identified several functional paralogs for each of the GAO, COS and KLS genes, pointing to redundancy in and robustness of the SL biosynthetic pathway. Gene functionality was further analyzed using CRISPR/Cas9 genome editing in C. intybus. Metabolite profiling of mutant C. intybus lines demonstrated a successful reduction in SL metabolite production. Together, this study increases our insights into the C. intybus SL biosynthetic pathway and paves the way for the engineering of C. intybus bitterness.

12.
New Phytol ; 239(4): 1521-1532, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37306056

RESUMO

A major advantage of using CRISPR/Cas9 for gene editing is multiplexing, that is, the simultaneous targeting of many genes. However, primary transformants typically contain hetero-allelic mutations or are genetic mosaic, while genetically stable lines that are homozygous are desired for functional analysis. Currently, a dedicated and labor-intensive effort is required to obtain such higher-order mutants through several generations of genetic crosses and genotyping. We describe the design and validation of a rapid and efficient strategy to produce lines of genetically identical plants carrying various combinations of homozygous edits, suitable for replicated analysis of phenotypical differences. This approach was achieved by combining highly multiplex gene editing in Zea mays (maize) with in vivo haploid induction and efficient in vitro generation of doubled haploid plants using embryo rescue doubling. By combining three CRISPR/Cas9 constructs that target in total 36 genes potentially involved in leaf growth, we generated an array of homozygous lines with various combinations of edits within three generations. Several genotypes show a reproducible 10% increase in leaf size, including a septuple mutant combination. We anticipate that our strategy will facilitate the study of gene families via multiplex CRISPR mutagenesis and the identification of allele combinations to improve quantitative crop traits.


Assuntos
Edição de Genes , Zea mays , Zea mays/genética , Sistemas CRISPR-Cas/genética , Genoma de Planta , Haploidia , Plantas Geneticamente Modificadas
13.
Front Cell Infect Microbiol ; 13: 1028496, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37256110

RESUMO

American Trypanosomiasis or Chagas disease (ChD), a major problem that is still endemic in large areas of Latin America, is caused by Trypanosoma cruzi. This agent holds a major antigen, cruzipain (Cz). Its C-terminal domain (C-T) is retained in the glycoprotein mature form and bears several post-translational modifications. Glycoproteins containing sulfated N-linked oligosaccharides have been mostly implicated in numerous specific procedures of molecular recognition. The presence of sulfated oligosaccharides was demonstrated in Cz, also in a minor abundant antigen with serine-carboxypeptidase (SCP) activity, as well as in parasite sulfatides. Sulfate-bearing glycoproteins in Trypanosomatids are targets of specific immune responses. T. cruzi chronically infected subjects mount specific humoral immune responses to sulfated Cz. Unexpectedly, in the absence of infection, mice immunized with C-T, but not with sulfate-depleted C-T, showed ultrastructural heart anomalous pathological effects. Moreover, the synthetic anionic sugar conjugate GlcNAc6SO3-BSA showed to mimic the N-glycan-linked sulfated epitope (sulfotope) humoral responses that natural Cz elicits. Furthermore, it has been reported that sulfotopes participate via the binding of sialic acid Ig-like-specific lectins (Siglecs) to sulfosialylated glycoproteins in the immunomodulation by host-parasite interaction as well as in the parasite infection process. Strikingly, recent evidence involved Cz-sulfotope-specific antibodies in the immunopathogenesis and infection processes during the experimental ChD. Remarkably, sera from chronically T. cruzi-infected individuals with mild disease displayed higher levels of IgG2 antibodies specific for sulfated glycoproteins and sulfatides than those with more severe forms of the disease, evidencing that T. cruzi sulfotopes are antigenic independently of the sulfated glycoconjugate type. Ongoing assays indicate that antibodies specific for sulfotopes might be considered biomarkers of human cardiac ChD progression, playing a role as predictors of stability from the early mild stages of chronic ChD.


Assuntos
Doença de Chagas , Trypanosoma cruzi , Humanos , Animais , Camundongos , Trypanosoma cruzi/metabolismo , Sulfatos/metabolismo , Sulfoglicoesfingolipídeos , Doença de Chagas/parasitologia , Glicoconjugados , Proteínas de Protozoários , Glicoproteínas/metabolismo , Oligossacarídeos
14.
J Phycol ; 59(3): 433-440, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37256696

RESUMO

Green seaweeds exhibit a wide range of morphologies and occupy various ecological niches, spanning from freshwater to marine and terrestrial habitats. These organisms, which predominantly belong to the class Ulvophyceae, showcase a remarkable instance of parallel evolution toward complex multicellularity and macroscopic thalli in the Viridiplantae lineage. Within the green seaweeds, several Ulva species ("sea lettuce") are model organisms for studying carbon assimilation, interactions with bacteria, life cycle progression, and morphogenesis. Ulva species are also notorious for their fast growth and capacity to dominate nutrient-rich, anthropogenically disturbed coastal ecosystems during "green tide" blooms. From an economic perspective, Ulva has garnered increasing attention as a promising feedstock for the production of food, feed, and biobased products, also as a means of removing excess nutrients from the environment. We propose that Ulva is poised to further develop as a model in green seaweed research. In this perspective, we focus explicitly on Ulva mutabilis/compressa as a model species and highlight the molecular data and tools that are currently available or in development. We discuss several areas that will benefit from future research or where exciting new developments have been reported in other Ulva species.


Assuntos
Clorófitas , Alga Marinha , Ulva , Ecossistema , Biologia de Sistemas
15.
Cytometry A ; 103(8): 624-630, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37219006

RESUMO

This 41-color panel has been designed to characterize both the lymphoid and the myeloid compartments in mice. The number of immune cells isolated from organs is often low, whilst an increasing number of factors need to be analyzed to gain a deeper understanding of the complexity of an immune response. With a focus on T cells, their activation and differentiation status, as well as their expression of several co-inhibitory and effector molecules, this panel also allows the analysis of ligands to these co-inhibitory molecules on antigen-presenting cells. This panel enables deep phenotypic characterization of CD4+ and CD8+ T cells, regulatory T cells, γδ T cells, NK T cells, B cells, NK cells, monocytes, macrophages, dendritic cells, and neutrophils. Whilst previous panels have focused on these topics individually, this is the first panel to enable simultaneous analysis of these compartments, thus enabling a comprehensive analysis with a limited number of immune cells/sample size. This panel is designed to analyze and compare the immune response in different mouse models of infectious diseases, but can also be extended to other disease models, for example tumors or autoimmune diseases. Here, we apply this panel to C57BL/6 mice infected with Plasmodium berghei ANKA, a mouse model of cerebral malaria.


Assuntos
Células Apresentadoras de Antígenos , Linfócitos T CD8-Positivos , Animais , Camundongos , Ligantes , Camundongos Endogâmicos C57BL , Monócitos
16.
Genome Biol ; 24(1): 6, 2023 01 13.
Artigo em Inglês | MEDLINE | ID: mdl-36639800

RESUMO

BACKGROUND: Testing an ever-increasing number of CRISPR components is challenging when developing new genome engineering tools. Plant biotechnology has few high-throughput options to perform iterative design-build-test-learn cycles of gene-editing reagents. To bridge this gap, we develop ITER (Iterative Testing of Editing Reagents) based on 96-well arrayed protoplast transfections and high-content imaging. RESULTS: We validate ITER in wheat and maize protoplasts using Cas9 cytosine and adenine base editors (ABEs), allowing one optimization cycle - from design to results - within 3 weeks. Given that previous LbCas12a-ABEs have low or no activity in plants, we use ITER to develop an optimized LbCas12a-ABE. We show that sequential improvement of five components - NLS, crRNA, LbCas12a, adenine deaminase, and linker - leads to a remarkable increase in activity from almost undetectable levels to 40% on an extrachromosomal GFP reporter. We confirm the activity of LbCas12a-ABE at endogenous targets in protoplasts and obtain base-edited plants in up to 55% of stable wheat transformants and the edits are transmitted to T1 progeny. We leverage these improvements to develop a highly mutagenic LbCas12a nuclease and a LbCas12a-CBE demonstrating that the optimizations can be broadly applied to the Cas12a toolbox. CONCLUSION: Our data show that ITER is a sensitive, versatile, and high-throughput platform that can be harnessed to accelerate the development of genome editing technologies in plants. We use ITER to create an efficient Cas12a-ABE by iteratively testing a large panel of vector components. ITER will likely be useful to create and optimize genome editing reagents in a wide range of plant species.


Assuntos
Sistemas CRISPR-Cas , Zea mays , Zea mays/genética , Triticum/genética , Edição de Genes/métodos , Mutagênese
17.
Nucleic Acids Res ; 51(7): e37, 2023 04 24.
Artigo em Inglês | MEDLINE | ID: mdl-36718951

RESUMO

Multiplex amplicon sequencing is a versatile method to identify genetic variation in natural or mutagenized populations through eco-tilling or multiplex CRISPR screens. Such genotyping screens require reliable and specific primer designs, combined with simultaneous gRNA design for CRISPR screens. Unfortunately, current tools are unable to combine multiplex gRNA and primer design in a high-throughput and easy-to-use manner with high design flexibility. Here, we report the development of a bioinformatics tool called SMAP design to overcome these limitations. We tested SMAP design on several plant and non-plant genomes and obtained designs for more than 80-90% of the target genes, depending on the genome and gene family. We validated the designs with Illumina multiplex amplicon sequencing and Sanger sequencing in Arabidopsis, soybean, and maize. We also used SMAP design to perform eco-tilling by tilling PCR amplicons across nine candidate genes putatively associated with haploid induction in Cichorium intybus. We screened 60 accessions of chicory and witloof and identified thirteen knockout haplotypes and their carriers. SMAP design is an easy-to-use command-line tool that generates highly specific gRNA and/or primer designs for any number of loci for CRISPR or natural variation screens and is compatible with other SMAP modules for seamless downstream analysis.


Assuntos
Variação Genética , Reação em Cadeia da Polimerase Multiplex , Software , Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas , Sistemas CRISPR-Cas , Genoma , Genótipo
18.
Plant Cell ; 35(1): 218-238, 2023 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-36066192

RESUMO

Ensuring food security for an ever-growing global population while adapting to climate change is the main challenge for agriculture in the 21st century. Although new technologies are being applied to tackle this problem, we are approaching a plateau in crop improvement using conventional breeding. Recent advances in CRISPR/Cas9-mediated gene engineering have paved the way to accelerate plant breeding to meet this increasing demand. However, many traits are governed by multiple small-effect genes operating in complex interactive networks. Here, we present the gene discovery pipeline BREEDIT, which combines multiplex genome editing of whole gene families with crossing schemes to improve complex traits such as yield and drought tolerance. We induced gene knockouts in 48 growth-related genes into maize (Zea mays) using CRISPR/Cas9 and generated a collection of over 1,000 gene-edited plants. The edited populations displayed (on average) 5%-10% increases in leaf length and up to 20% increases in leaf width compared with the controls. For each gene family, edits in subsets of genes could be associated with enhanced traits, allowing us to reduce the gene space to be considered for trait improvement. BREEDIT could be rapidly applied to generate a diverse collection of mutants to identify promising gene modifications for later use in breeding programs.


Assuntos
Edição de Genes , Zea mays , Zea mays/genética , Sistemas CRISPR-Cas/genética , Plantas Geneticamente Modificadas/genética , Herança Multifatorial , Melhoramento Vegetal , Genoma de Planta/genética
19.
Biol Psychol ; 176: 108466, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36455805

RESUMO

Physical exercise has been shown to enhance memory and to increase neuroplasticity. Rodent studies have revealed modulating effects of signaling molecules of the immune system (cytokines) on hippocampal plasticity and memory. Acute and chronic exercise have been both found to alter the number and function of immune cells. Thus, physical exercise might enhance neuroplasticity via an altered immune response. In this study we tested whether multiple repetitions of a vocabulary learning task combined with a bout of cardiovascular exercise enhances learning in humans and whether memory improvements correlated with acute exercise-induced cytokine changes. Data of 52 participants (20-40 years of age) who were randomly assigned to a cardiovascular exercise group (cycling) or a control group (stretching) were analyzed. During the 10-week treatment, participants completed 18 learning-exercise sessions. In each of these sessions, the vocabulary learning task was always performed immediately before exercising started. To assess acute exercise-induced changes in cytokine levels, blood sampling was performed at rest and immediately after exercising in two of the sessions. Learning success measured as increase in learning across all sessions and vocabulary retention four weeks after the treatment had ended did not differ between groups. The cycling group showed a relatively larger acute increase in IL-6, IL-1ra, IL-4, and IFN-γ compared to the stretching group. Exploratory analyses revealed significant positive associations between within-session learning and acute exercise-induced increases in IL-6 and IL-1ra in the cycling group only. These results suggest that the immune system may act as a mediator of exercise-induced cognitive benefits.


Assuntos
Citocinas , Proteína Antagonista do Receptor de Interleucina 1 , Humanos , Adulto Jovem , Exercício Físico/fisiologia , Interleucina-6 , Aprendizagem/fisiologia , Adulto
20.
Curr Protoc ; 2(12): e608, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36469612

RESUMO

CRISPR/Cas is now the standard technique to generate novel plant genotypes. However, optimizing the efficiency of the system continues to be an aspect of research and development. One of the improvements for increasing mutagenesis efficiency in different species is the application of heat stress. However, many experimental setups are limited by the requirement of using dedicated climate chambers to impose heat stress and by difficulties in the phenotyping of soil-grown plants. Here, we describe a simplified heat stress assay for in vitro-grown plants that can be completed in 6 days using commonly available laboratory equipment. We show that three 24-hr heat shocks (3×HS) at 37°C alternated with 24 hr of recovery at 21°C efficiently increases indel rates of LbCas12a and Cas9. We illustrate how visual mutant phenotypes (pds3 and gl1) can assist in quantifying genome editing efficiency, and describe how to quantify genome editing efficiency using genotyping by Sanger sequencing. We also provide a support protocol to efficiently clone a CRISPR expression vector in a single step. Together, our methods allow researchers to increase CRISPR-induced mutations using a low-tech setup in plants. © 2022 Wiley Periodicals LLC. Basic Protocol 1: 3×HS protocol Basic Protocol 2: Genotyping by Sanger sequencing Support Protocol: One-step cloning of a CRISPR expression vector.


Assuntos
Sistemas CRISPR-Cas , Edição de Genes , Edição de Genes/métodos , Sistemas CRISPR-Cas/genética , Plantas/genética , Mutagênese , Resposta ao Choque Térmico/genética
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