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1.
Infect Genet Evol ; 104: 105358, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36057423

RESUMO

OBJECTIVES: The long-acting injectable (LAI) cabotegravir (CAB) and rilpivirine (RPV) treatment offers important advantages over oral ART (antiretroviral therapy), however baseline factors possibly contributing to the CAB/RPV treatment failure were identified. The purpose of this study was to describe the frequency of virologic factors previously influencing efficacy of this treatment, namely RPV and CAB resistance-associated mutations (RAMs) and A1/A6 subtype among naïve and treatment-experienced HIV-1-infected patients from Poland. METHODS: The following datasets of HIV-1 sequences were analysed: 4809 protease and reverse transcriptase (PR/RT) sequences obtained from 4649 Polish Caucasian patients (4122 naive and 687 non-naïve) supplemented with integrase (PR/RT/INT) sequences in 1217 cases (942 naïve and 275 non-naïve). Sub-subtypes A were assigned by phylogenetic methods. Major and minor CAB and RPV RAMs were determined according to the IAS-USA 2019 list, while minor RAMs were additionally defined based on the Stanford database algorithm. RESULTS: Subtype A1/A6 frequency ranged from 6.11% in ART failing cases with PR/RT sequences only, to 15.92% for the PR/RT/INT treatment-naïve dataset, while RPV RAMs were found in up to 5.89% of treatment-naïve and 14.56% of ART failing cases. Regardless treatment history, only <1% sequences had combination of two factors (RPV RAMs and A1/A6 subtype). Furthermore, CAB RAMs were found in 1.27% of treatment-naïve and 14.54% of experienced patients. CONCLUSIONS: Despite notable frequency of subtype A1/A6 or CAB/RPV RAMs analysed separately, combination of at least two factors previously associated with failure or this treatment is rare. As subtype A1/A6 becomes more common across real-life cohorts continued subtyping and RAM screening will remain of key importance for LAI treatment implementation. Sequence data from this article have been deposited in GenBank under accession numbers: GU906860, GU906864, GU906871-GU906874, JQ305750-JQ305791, KC409134-KC409222, KM057341-KM057362, KM283892-KM284490, KT340108-KT340205, MZ468643-MZ468894, MZ671788-MZ671823, OP298017-OP302727.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Soropositividade para HIV , HIV-1 , Fármacos Anti-HIV/farmacologia , Fármacos Anti-HIV/uso terapêutico , Antirretrovirais/uso terapêutico , Dicetopiperazinas , Farmacorresistência Viral/genética , Infecções por HIV/tratamento farmacológico , HIV-1/genética , Humanos , Integrases/genética , Integrases/uso terapêutico , Peptídeo Hidrolases/genética , Filogenia , Piridonas , DNA Polimerase Dirigida por RNA/genética , Rilpivirina/uso terapêutico
2.
Physiol Rep ; 10(17): e15443, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-36082952

RESUMO

A recent article described a thickening of the glomerular basement membrane (GBM) along with changes in the expression of key components of the extracellular matrix in 6-month-old NPHS2-Cre transgenic mice, which express the Cre recombinase specifically in podocytes. This transgenic line has been widely used to characterize the implication of candidate genes in glomerular diseases in younger mice. Using a different mouse strain (C57BL/6J) than the previous report (129S6/SvEvTac), we sought to characterize 3- and 6-month-old NPHS2-Cre+/- mice in control and pathological conditions. At baseline, there was no difference in renal function and histology between control and NPHS2-Cre+/- mice. Notably, GBM thickness evaluated by transmission electron microscopy was similar between the two groups. We then induced an immune-mediated severe glomerular insult, the anti-glomerular basement membrane glomerulonephritis model (anti-GBM-GN) in 3-month-old control and NPHS2-Cre+/- mice. NPHS2-Cre+/- mice exhibited the same alterations in renal function and structure as control mice. In summary, our study strongly suggests that NPHS2-Cre+/- transgenic mice on a C57BL/6J background can be safely used for podocyte-specific gene inactivation in control conditions and in the anti-GBM-GN model.


Assuntos
Glomerulonefrite , Podócitos , Animais , Membrana Basal/metabolismo , Glomerulonefrite/metabolismo , Integrases , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Transgênicos , Podócitos/metabolismo
3.
Commun Biol ; 5(1): 979, 2022 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-36114373

RESUMO

Transgenic animals expressing fluorescent proteins are widely used to label specific cells and proteins. By using a split Cre recombinase fused with mCherry-binding nanobodies or designed ankyrin repeat proteins, we created Cre recombinase dependent on red fluorescent protein (RFP) (Cre-DOR). Functional binding units for monomeric RFPs are different from those for polymeric RFPs. We confirmed selective target RFP-dependent gene expression in the mouse cerebral cortex using stereotaxic injection of adeno-associated virus vectors. In estrogen receptor-beta (Esr2)-mRFP1 mice and gastrin-releasing peptide receptor (Grpr)-mRFP1 rats, we confirmed that Cre-DOR can be used for selective tracing of the neural projection from RFP-expressing specific neurons. Cellular localization of RFPs affects recombination efficiency of Cre-DOR, and light and chemical-induced nuclear translocation of an RFP-fused protein can modulate Cre-DOR efficiency. Our results provide a method for manipulating gene expression in specific cells expressing RFPs and expand the repertory of nanobody-based genetic tools.


Assuntos
Receptores da Bombesina , Anticorpos de Domínio Único , Animais , Integrases , Proteínas Luminescentes , Camundongos , Camundongos Transgênicos , Ratos , Receptores de Estrogênio , Anticorpos de Domínio Único/genética
4.
Int J Mol Sci ; 23(17)2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36077578

RESUMO

CRISPR-Cas systems empower prokaryotes with adaptive immunity against invasive mobile genetic elements. At the first step of CRISPR immunity adaptation, short DNA fragments from the invaders are integrated into CRISPR arrays at the leader-proximal end. To date, the mechanism of recognition of the leader-proximal end remains largely unknown. Here, in the Sulfolobus islandicus subtype I-A system, we show that mutations destroying the proximal region reduce CRISPR adaptation in vivo. We identify that a stem-loop structure is present on the leader-proximal end, and we demonstrate that Cas1 preferentially binds the stem-loop structure in vitro. Moreover, we demonstrate that the integrase activity of Cas1 is modulated by interacting with a CRISPR-associated factor Csa3a. When translocated to the CRISPR array, the Csa3a-Cas1 complex is separated by Csa3a binding to the leader-distal motif and Cas1 binding to the leader-proximal end. Mutation at the leader-distal motif reduces CRISPR adaptation efficiency, further confirming the in vivo function of leader-distal motif. Together, our results suggest a general model for binding of Cas1 protein to a leader motif and modulation of integrase activity by an accessory factor.


Assuntos
Proteínas Associadas a CRISPR , Sulfolobus , Proteínas Associadas a CRISPR/metabolismo , Sistemas CRISPR-Cas , Integrases/metabolismo , Motivos de Nucleotídeos , Sulfolobus/genética , Sulfolobus/metabolismo
5.
Cells ; 11(17)2022 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-36078177

RESUMO

Cre/loxP recombination is a well-established technique increasingly used for modifying DNA both in vitro and in vivo. Nucleotide alterations can be edited in the genomes of mammalian cells, and genetic switches can be designed to target the expression or excision of a gene in any tissue at any time in animal models. In this study, we propose a system which worked via the Cre/loxP switch gene and DsRed/emGFP dual-color fluorescence imaging. Mesenchymal stem cells (MSCs) can be used to regenerate damaged tissue because of their differentiation capacity. Although previous studies have presented evidence of fusion of transplanted MSCs with recipient cells, the possibility of fusion in such cases remains debated. Moreover, the effects and biological implications of the fusion of MSCs at the tissue and organ level have not yet been elucidated. Thus, the method for determining this issue is significant and the models we proposed can illustrate the question. However, the transgenic rats exhibited growth slower than that of wild-type rats over several weeks. The effects on the stemness, proliferation, cell cycle, and differentiation ability of bone marrow-derived rat MSCs (BM-rMSCs) from the models were examined to ensure our design was appropriate for the in vivo application. We demonstrated that MSC surface markers were maintained in DsRed and Cre transgenic rMSCs (DsRed-rMSCs and Cre-rMSCs, respectively). A WST-8 assay revealed decreased proliferative activity in these DsRed-rMSCs and Cre-rMSCs; this result was validated through cell counting. Furthermore, cell cycle analysis indicated a decrease in the proportion of G1-phase cells and a concomitant increase in the proportion of S-phase cells. The levels of cell cycle-related proteins also decreased in the DsRed-rMSCs and Cre-rMSCs, implying decelerated phase transition. However, the BM-rMSCs collected from the transgenic rats did not exhibit altered adipogenesis, osteogenesis, or chondrogenesis. The specific markers of these types of differentiation were upregulated after induction. Therefore, BM-rMSCs from DsRed and Cre transgenic models can be used to investigate the behavior of MSCs and related mechanisms. Such application may further the development of stem cell therapy for tissue damage and other diseases.


Assuntos
Medula Óssea , Células-Tronco Mesenquimais , Animais , Integrases , Proteínas Luminescentes , Mamíferos , Células-Tronco Mesenquimais/metabolismo , Ratos , Ratos Transgênicos
6.
Biochem Biophys Res Commun ; 625: 31-37, 2022 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-35944361

RESUMO

Dilated cardiomyopathy, a type of heart muscle disease defined by the presence of left ventricular dilatation and contractile dysfunction, is an important cause of sudden cardiac death and heart failure. O-GlcNAcylation is an important post-translational modification of proteins by the addition of O-GlcNAc moieties at serine or threonine residues. Several studies have shown that proper control of O-GlcNAcylation is required for maintaining physiological function of heart by using Ogt (O-GlcNAc transferase) cardiomyocyte-specific knockout mouse models. In this study, we generated a new mouse model (αSMA-Ogt KO) in which Ogt was deleted in both cardiomyocytes and smooth muscle cells by crossing Ogt floxed mice with αSMA-Cre mice. αSMA-Cre-mediated Ogt deletion in mice led to severe postnatal lethality; the survived mice were smaller than control mice, had dilated hearts, and showed observable signs of heart failure. Moreover, the αSMA-Ogt KO heart had more apoptotic cells and fibrosis. The arteries of αSMA-Ogt KO mice exhibited significantly reduced expression of contractile genes and a trend towards arterial stiffness. In conclusion, our data emphasize the importance of OGT in maintaining normal heart function and reveal a novel role of OGT in regulating arterial contractility.


Assuntos
Insuficiência Cardíaca , Músculo Liso Vascular , Animais , Insuficiência Cardíaca/genética , Insuficiência Cardíaca/metabolismo , Integrases , Camundongos , Camundongos Knockout , Músculo Liso Vascular/metabolismo , Miócitos Cardíacos/metabolismo , Miócitos de Músculo Liso/metabolismo , N-Acetilglucosaminiltransferases/metabolismo
7.
J Bone Miner Metab ; 40(5): 839-852, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35947192

RESUMO

INTRODUCTION: Osteoblasts require substantial amounts of energy to synthesize the bone matrix and coordinate skeleton mineralization. This study analyzed the effects of mitochondrial dysfunction on bone formation, nano-organization of collagen and apatite, and the resultant mechanical function in mouse limbs. MATERIALS AND METHODS: Limb mesenchyme-specific Tfam knockout (Tfamf/f;Prx1-Cre: Tfam-cKO) mice were analyzed morphologically and histologically, and gene expressions in the limb bones were assessed by in situ hybridization, qPCR, and RNA sequencing (RNA-seq). Moreover, we analyzed the mitochondrial function of osteoblasts in Tfam-cKO mice using mitochondrial membrane potential assay and transmission electron microscopy (TEM). We investigated the pathogenesis of spontaneous bone fractures using immunohistochemical analysis, TEM, birefringence analyzer, microbeam X-ray diffractometer and nanoindentation. RESULTS: Forelimbs in Tfam-cKO mice were significantly shortened from birth, and spontaneous fractures occurred after birth, resulting in severe limb deformities. Histological and RNA-seq analyses showed that bone hypoplasia with a decrease in matrix mineralization was apparent, and the expression of type I collagen and osteocalcin was decreased in osteoblasts of Tfam-cKO mice, although Runx2 expression was unchanged. Decreased type I collagen deposition and mineralization in the matrix of limb bones in Tfam-cKO mice were associated with marked mitochondrial dysfunction. Tfam-cKO mice bone showed a significantly lower Young's modulus and hardness due to poor apatite orientation which is resulted from decreased osteocalcin expression. CONCLUSION: Mice with limb mesenchyme-specific Tfam deletions exhibited spontaneous limb bone fractures, resulting in severe limb deformities. Bone fragility was caused by poor apatite orientation owing to impaired osteoblast differentiation and maturation.


Assuntos
Fraturas Espontâneas , Animais , Apatitas , Colágeno Tipo I/metabolismo , Proteínas de Ligação a DNA/metabolismo , Fraturas Espontâneas/metabolismo , Proteínas de Grupo de Alta Mobilidade/metabolismo , Integrases , Mesoderma/metabolismo , Camundongos , Camundongos Knockout , Osteoblastos/metabolismo , Osteocalcina/metabolismo
8.
Biomolecules ; 12(8)2022 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-36009054

RESUMO

The aim of this study was to quantify ESKAPEE bacteria, genes encoding resistance to antibiotics targeting this group of pathogens, as well as integrase genes in municipal wastewater and river water. Environmental DNA was extracted from the collected samples and used in deep sequencing with the Illumina TruSeq kit. The abundance of bacterial genera and species belonging to the ESKAPEE group, 400 ARGs associated with this microbial group, and three classes of integrase genes were determined. A taxonomic analysis revealed that Acinetobacter was the dominant bacterial genus, whereas Acinetobacter baumannii and Escherichia coli were the dominant bacterial species. The analyzed samples were characterized by the highest concentrations of the following ARGs: blaGES, blaOXA-58, blaTEM, qnrB, and qnrS. Acinetobacter baumannii, E. coli, and genes encoding resistance to ß-lactams (blaVEB-1, blaIMP-1, blaGES, blaOXA-58, blaCTX-M, and blaTEM) and fluoroquinolones (qnrS) were detected in samples of river water collected downstream from the wastewater discharge point. The correlation analysis revealed a strong relationship between A. baumannii (bacterial species regarded as an emerging human pathogen) and genes encoding resistance to all tested groups of antimicrobials. The transmission of the studied bacteria (in particular A. baumannii) and ARGs to the aquatic environment poses a public health risk.


Assuntos
Acinetobacter baumannii , Águas Residuárias , Acinetobacter baumannii/genética , Antibacterianos/análise , Antibacterianos/farmacologia , Bactérias/genética , Escherichia coli , Humanos , Integrases , Polônia , Água/análise
9.
Mol Pain ; 18: 17448069221119614, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-36000342

RESUMO

Projection neurons belonging to the anterolateral system (ALS) underlie the perception of pain, skin temperature and itch. Many ALS cells are located in laminae III-V of the dorsal horn and the adjacent lateral white matter. However, relatively little is known about the excitatory synaptic input to these deep ALS cells, and therefore about their engagement with the neuronal circuitry of the region. We have used a recently developed mouse line, Phox2a::Cre, to investigate a population of deep dorsal horn ALS neurons known as "antenna cells", which are characterised by dense innervation from peptidergic nociceptors, and to compare these with other ALS cells in the deep dorsal horn and lateral white matter. We show that these two classes differ, both in the density of excitatory synapses, and in the source of input at these synapses. Peptidergic nociceptors account for around two-thirds of the excitatory synapses on the antenna cells, but for only a small proportion of the input to the non-antenna cells. Conversely, boutons with high levels of VGLUT2, which are likely to originate mainly from glutamatergic spinal neurons, account for only ∼5% of the excitatory synapses on antenna cells, but for a much larger proportion of the input to the non-antenna cells. VGLUT1 is expressed by myelinated low-threshold mechanoreceptors and corticospinal axons, and these innervate both antenna and non-antenna cells. However, the density of VGLUT1 input to the non-antenna cells is highly variable, consistent with the view that these neurons are functionally heterogeneous.


Assuntos
Esclerose Amiotrófica Lateral , Animais , Proteínas de Homeodomínio/genética , Integrases , Camundongos , Neurônios/fisiologia , Células do Corno Posterior/fisiologia , Medula Espinal , Corno Dorsal da Medula Espinal
10.
Drug Discov Ther ; 16(4): 198-199, 2022 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-36002310

RESUMO

This study was aimed at assessing the adherence and incorrect drug intake associated with changes in the dosing schedule of raltegravir, the first integrase strand transfer inhibitor, from 400 mg twice a day (BID) to 600 mg × 2 tablets once a day (QD) in human immunodeficiency virus (HIV)-infected patients. Medication adherence over 1 month was evaluated in 25 male patients using the 100-mm visual analog scale (VAS) at the 3-day recall pill count and during pharmacist counseling after the first post-change visit. VAS scores before and after the raltegravir formulation change were compared. Medication adherence increased from 96 ± 4.3 mm (BID) to 100 ± 0.3 mm (QD) (P < 0.05). The patients exhibited improved medication adherence; however, three patients incorrectly took the drug when the formulation changed. This discovery can be used to facilitate the treatment of HIV-infected patients to increase treatment suitability and safety.


Assuntos
Infecções por HIV , Esquema de Medicação , Infecções por HIV/tratamento farmacológico , Humanos , Integrases/uso terapêutico , Masculino , Adesão à Medicação , Erros de Medicação , Raltegravir Potássico/efeitos adversos , Comprimidos/uso terapêutico
11.
Int J Mol Sci ; 23(16)2022 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-36012727

RESUMO

A popular approach to spatiotemporally target genes using the loxP/Cre recombination system is stereotaxic microinjection of adeno-associated virus (AAV) expressing Cre recombinase (AAV_Cre) in specific neuronal structures. Here, we report that AAV_Cre microinjection in the ventral tegmental area (VTA) of ErbB4 Cyt-1-floxed (ErbB4 Cyt-1fl/fl) mice at titers commonly used in the literature (~1012-1013 GC/mL) can have neurotoxic effects on dopaminergic neurons and elicit behavioral abnormalities. However, these effects of AAV_Cre microinjection are independent of ErbB4 Cyt-1 recombination because they are also observed in microinjected wild-type (WT) controls. Mice microinjected with AAV_Cre (1012-1013 GC/mL) exhibit reductions of tyrosine hydroxylase (TH) and dopamine transporter (DAT) expression, loss of dopaminergic neurons, and they behaviorally become hyperactive, fail to habituate in the open field and exhibit sensorimotor gating deficits compared to controls microinjected with AAV_GFP. Importantly, these AAV_Cre non-specific effects are: (1) independent of serotype, (2) occur with vectors expressing either Cre or Cre-GFP fusion protein and (3) preventable by reducing viral titers by 1000-fold (1010 GC/mL), which retains sufficient recombination activity to target floxed genes. Our studies emphasize the importance of including AAV_Cre-injected WT controls in experiments because recombination-independent effects on gene expression, neurotoxicity and behaviors could be erroneously attributed to consequences of gene ablation.


Assuntos
Dependovirus , Neurônios Dopaminérgicos , Transdução Genética , Animais , Dependovirus/genética , Dependovirus/metabolismo , Neurônios Dopaminérgicos/metabolismo , Integrases/genética , Integrases/metabolismo , Camundongos , Receptor ErbB-4/metabolismo , Tirosina 3-Mono-Oxigenase/genética , Tirosina 3-Mono-Oxigenase/metabolismo
12.
Int J Mol Sci ; 23(16)2022 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-36012650

RESUMO

The clustering of transgenes at a chromosome location minimizes the number of segregating loci that needs to be introgressed to field cultivars. Transgenes could be efficiently stacked through site-specific recombination and a recombinase-mediated in planta gene stacking process was described previously in tobacco based on the Mycobacteriophage Bxb1 site-specific integration system. Since this process requires a recombination site in the genome, this work describes the generation of target sites in the Japonica rice genome. Agrobacterium-mediated gene transfer yielded ~4000 random-insertion lines. Seven lines met the criteria of being single copy, not close to a centromere, not inserted within or close to a known gene or repetitive DNA, having precise recombination site sequences on both ends, and able to express the reporter gene. Each target line tested was able to accept the site-specific integration of a new gfp-containing plasmid and in three of those lines, we regenerated fertile plants. These target lines could be used as foundation lines for stacking new traits into Japonica rice.


Assuntos
Oryza , Integrases/genética , Oryza/genética , Plantas Geneticamente Modificadas/genética , Recombinases/genética , Recombinação Genética , Tabaco/genética , Transgenes
13.
Sheng Wu Gong Cheng Xue Bao ; 38(8): 2912-2927, 2022 Aug 25.
Artigo em Chinês | MEDLINE | ID: mdl-36002420

RESUMO

Very long chain polyunsaturated fatty acids (VLC-PUFAs) are unique fatty acids in tissues of mammals such as retina and testis, and the key enzyme of its biosynthesis is very long chain fatty acid elongase 4 (Elovl4). Development of an animal model of tissue-specific knockout of Elovl4 gene is conducive to the in-depth study of the biological function of VLC-PUFAs. Therefore, we constructed Stra8-Cre mice and Elovl4 floxed mice based on Cre/loxP system, and obtained the (Elovl4[flox/+], Stra8-Cre) heterozygous knockout mice by hybridization. Subsequently, female mice were selected to cross with male mice with homozygous Elovl4[flox/flox] to gain homozygous mice (Elovl4[flox/flox], Stra8-Cre) through genotype identification and screening. RT-PCR, qRT-PCR, Western blotting, immunohistochemistry and immunofluorescence techniques were used to detect the knock-out efficiency of Elovl4 in testis. The expression of Elovl4 in testis of both heterozygous and homozygous knockout mice were significantly down-regulated at mRNA and protein levels, but were not affected in other tissues. In summary, we constructed a mouse model with specific knockout of Elovl4 gene in testis, which provides a reliable animal model for studying the effect of VLC-PUFAs on the reproductive function of male mice and the underpinning molecular mechanisms.


Assuntos
Proteínas do Olho/metabolismo , Proteínas de Membrana/metabolismo , Testículo , Animais , Modelos Animais de Doenças , Proteínas do Olho/genética , Feminino , Técnicas de Inativação de Genes , Integrases , Masculino , Mamíferos/genética , Mamíferos/metabolismo , Proteínas de Membrana/genética , Camundongos , Camundongos Knockout , Testículo/metabolismo
14.
Am J Physiol Heart Circ Physiol ; 323(3): H528-H534, 2022 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-35930445

RESUMO

Genetically modified mice are widely used to recapitulate human diseases. Atherosclerosis can be induced in mice with low-density lipoprotein receptor (Ldlr)-deficiency and a high-fat diet (HFD). Disintegrin and metalloproteinase-17 (ADAM17) in the smooth muscle cell (SMC) contribute to vascular pathologies, and hence its role in atherosclerosis was investigated. Adam17 deletion in SMCs by Sm22α-Cre driver (Ldlr-/-/Adam17Sm22Cre) and HFD resulted in severe skin lesions in >70% of mice, associated with skin inflammation, which was not observed in Ldlr-/--HFD, nor in mice with SMC deficiency of Adam17 by a different Cre driver (Ldlr-/-/Adam17Myh11Cre). We found that Sm22α is highly expressed in keratinocytes (compared with SMCs), which could underlie the observed skin lesion in Ldlr-/-/Adam17Sm22Cre-HFD. Although expression of Sm22α in non-SMCs has been reported, this is the first study demonstrating a severe side effect resulting from the off-target expression of Sm22α-Cre, resulting in ADAM17 loss in keratinocytes that led to a moribund state.NEW & NOTEWORTHY Although Sm22α-Cre is commonly used to target gene deletion in smooth muscle cells, Sm22α-derived Adam17 deletion resulted in unexpected severe skin lesions following high-fat diet feeding in a model of atherosclerosis. Adam17 deletion by a different SMC driver, Myh11-Cre, did not result in skin lesions in the same atherosclerosis model. Sm22α is highly expressed in keratinocytes, causing ectopic loss of ADAM17 in keratinocytes that caused significant epidermal lesions when combined with a high-fat diet.


Assuntos
Aterosclerose , Músculo Liso Vascular , Animais , Aterosclerose/patologia , Humanos , Integrases , Queratinócitos/patologia , Camundongos , Camundongos Knockout , Músculo Liso Vascular/metabolismo , Miócitos de Músculo Liso/metabolismo
15.
PLoS One ; 17(8): e0272141, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35925937

RESUMO

The cholinergic system is an important modulator of brain processes. It contributes to the regulation of several cognitive functions and emotional states, hence altering behaviors. Previous works showed that cholinergic (nicotinic) receptors of the prefrontal cortex are needed for adapted social behaviors. However, these data were obtained in mutant mice that also present alterations of several neurotransmitter systems, in addition to the cholinergic system. ChAT-IRES-Cre mice, that express the Cre recombinase specifically in cholinergic neurons, are useful tools to investigate the role of the cholinergic circuits in behavior. However, their own behavioral phenotype has not yet been fully characterized, in particular social behavior. In addition, the consequences of aging on the cholinergic system of ChAT-IRES-Cre mice has never been studied, despite the fact that aging is known to compromise the cholinergic system efficiency. The aim of the current study was thus to characterize the social phenotype of ChAT-IRES-Cre mice both at young (2-3 months) and middle (10-11 months) ages. Our results reveal an alteration of the cholinergic system, evidenced by a decrease of ChAT, CHT and VAChT gene expression in the striatum of the mice, that was accompanied by mild social disturbances and a tendency towards anxiety. Aging decreased social dominance, without being amplified by the cholinergic alterations. Altogether, this study shows that ChAT-IRES-Cre mice are useful models for studying the cholinergic system's role in social behavior using appropriate modulating technics (optogenetic or DREADD).


Assuntos
Colina O-Acetiltransferase , Neurônios Colinérgicos , Animais , Colina O-Acetiltransferase/metabolismo , Colinérgicos , Neurônios Colinérgicos/metabolismo , Integrases , Camundongos , Camundongos Transgênicos , Comportamento Social
16.
Development ; 149(16)2022 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-35980363

RESUMO

Visualizing cell shapes and interactions of differentiating cells is instrumental for understanding organ development and repair. Across species, strategies for stochastic multicolour labelling have greatly facilitated in vivo cell tracking and mapping neuronal connectivity. Yet integrating multi-fluorophore information into the context of developing zebrafish tissues is challenging given their cytoplasmic localization and spectral incompatibility with common fluorescent markers. Inspired by Drosophila Raeppli, we developed FRaeppli (Fish-Raeppli) by expressing bright membrane- or nuclear-targeted fluorescent proteins for efficient cell shape analysis and tracking. High spatiotemporal activation flexibility is provided by the Gal4/UAS system together with Cre/lox and/or PhiC31 integrase. The distinct spectra of the FRaeppli fluorescent proteins allow simultaneous imaging with GFP and infrared subcellular reporters or tissue landmarks. We demonstrate the suitability of FRaeppli for live imaging of complex internal organs, such as the liver, and have tailored hyperspectral protocols for time-efficient acquisition. Combining FRaeppli with polarity markers revealed previously unknown canalicular topologies between differentiating hepatocytes, reminiscent of the mammalian liver, suggesting common developmental mechanisms. The multispectral FRaeppli toolbox thus enables the comprehensive analysis of intricate cellular morphologies, topologies and lineages at single-cell resolution in zebrafish.


Assuntos
Integrases , Peixe-Zebra , Animais , Animais Geneticamente Modificados , Proteínas de Fluorescência Verde/metabolismo , Integrases/metabolismo , Mamíferos/metabolismo , Neurônios/metabolismo , Peixe-Zebra/metabolismo
17.
Nat Commun ; 13(1): 4152, 2022 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-35858965

RESUMO

Site-specific recombination (SSR) is an important tool in synthetic biology, but its applications are limited by the inability to predictably tune SSR reaction rates. Facile rate manipulation could be achieved by modifying the DNA substrate sequence; however, this approach lacks rational design principles. Here, we develop an integrated experimental and computational method to engineer the DNA attachment sequence attP for predictably modulating the inversion reaction mediated by the recombinase Bxb1. After developing a qPCR method to measure SSR reaction rate, we design, select, and sequence attP libraries to inform a machine-learning model that computes Bxb1 inversion rate as a function of attP sequence. We use this model to predict reaction rates of attP variants in vitro and demonstrate their utility in gene circuit design in Escherichia coli. Our high-throughput, model-guided approach for rationally tuning SSR reaction rates enhances our understanding of recombinase function and expands the synthetic biology toolbox.


Assuntos
Bacteriófagos , Recombinação Genética , Bacteriófagos/genética , Sequência de Bases , DNA/genética , Escherichia coli/genética , Escherichia coli/metabolismo , Integrases/genética , Integrases/metabolismo , Recombinases/genética , Recombinases/metabolismo
18.
Microb Pathog ; 170: 105669, 2022 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-35809754

RESUMO

OBJECTIVE: To investigate the distribution of class 1 integrons and their variable regional molecular characteristics, as well as the diversity of promoter and drug sensitivity of CR-Eco (carbapenem-resistant E. coli) strains. METHOD: A total of 117 CR-Eco strains, collected between 2012.01 and 2019.12, underwent fully automated bacterial identification and sensitization using VITEK-2 Compact and supplemented by K-B assay. PCR was employed to screen for class 1 integrase genes and integron variable regions, while the promoter type and variable region gene cassette characteristics were determined by sequencing analysis. RESULTS: The positive rate of the class 1 integron of the CR-Eco strains was 83.70% (92/117) herein. Moreover, class 1 integrase-positive strains exhibited statistically significant resistance to aztreonam, ceftazidime, ciprofloxacin, ceftriaxone, gentamicin, meropenem, and trimethoprim-sulfamethoxazole compared to integron-negative strains (P < 0.05). Variable regions were observed in 77 of the 92 class 1 integrase-positive strains. In addition, seven gene cassettes were detected, namely dfrA17-aadA5, aadA22, dfrA12-aadA2, dfrA12, dfrA17, dfrA27 and aadA. Finally, five types of class 1 integron variable region promoters were identified in those 77 strains, including PcW, PcH1, PcWTGN-10, PcH1TGN-10, and P2, which were detected in 48, 18, 8, 2, and 1 strains, respectively. CONCLUSION: The primary integrator variable region gene cassettes of this class were dfrA and aadA. The integron-positive strains displayed simultaneous high resistance to multiple antimicrobial drugs. The integrator variable region promoters of the CR-Eco strains are primarily weak and can potentially form and spread drug resistance.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos , Integrons , Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Farmacorresistência Bacteriana/genética , Escherichia coli/genética , Integrases/genética , Integrons/genética
19.
Microbiol Spectr ; 10(4): e0147822, 2022 Aug 31.
Artigo em Inglês | MEDLINE | ID: mdl-35852337

RESUMO

Moloney murine leukemia virus (MLV) infects BALB/c mice and induces T-cell lymphoma in mice. Retroviral integration is mediated by the interaction of the MLV integrase (IN) with members of the bromodomain and extraterminal motif (BET) protein family (BRD2, BRD3, and BRD4). The introduction of the W390A mutation into MLV IN abolishes the BET interaction. Here, we compared the replication of W390A MLV to that of wild-type (WT) MLV in adult BALB/c mice to study the role of BET proteins in replication, integration, and tumorigenesis in vivo. Comparing WT and W390A MLV infections revealed similar viral loads in the blood, thymus, and spleen cells. Interestingly, W390A MLV integration was retargeted away from GC-enriched genomic regions. However, both WT MLV- and W390A MLV-infected mice developed T-cell lymphoma after similar latencies represented by an enlarged thymus and spleen and multiorgan tumor infiltration. Integration site sequencing from splenic tumor cells revealed clonal expansion in all WT MLV- and W390A MLV-infected mice. However, the integration profiles of W390A MLV and WT MLV differed significantly. Integrations were enriched in enhancers and promoters, but compared to the WT, W390A MLV integrated less frequently into enhancers and more frequently into oncogene bodies such as Notch1 and Ppp1r16b. We conclude that host factors direct MLV in vivo integration site selection. Although BET proteins target WT MLV integration preferentially toward enhancers and promoters, insertional lymphomagenesis can occur independently from BET, likely due to the intrinsically strong enhancer/promoter of the MLV long terminal repeat (LTR). IMPORTANCE In this study, we have shown that the in vivo replication of murine leukemia virus happens independently of BET proteins, which are key host determinants involved in retroviral integration site selection. This finding opens a new research line in the discovery of alternative viral or host factors that may complement the dominant host factor. In addition, our results show that BET-independent murine leukemia virus uncouples insertional mutagenesis from gene enhancers, although lymphomagenesis still occurs despite the lack of an interaction with BET proteins. Our findings also have implications for the engineering of BET-independent MLV-based vectors for gene therapy, which may not be a safe alternative.


Assuntos
Linfoma de Células T , Proteínas Nucleares , Animais , Genômica , Integrases/genética , Integrases/metabolismo , Vírus da Leucemia Murina/genética , Vírus da Leucemia Murina/metabolismo , Camundongos , Proteínas Nucleares/genética , Proteínas Nucleares/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Integração Viral/genética
20.
Nature ; 608(7921): 217-225, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35896746

RESUMO

Biological processes depend on the differential expression of genes over time, but methods to make physical recordings of these processes are limited. Here we report a molecular system for making time-ordered recordings of transcriptional events into living genomes. We do this through engineered RNA barcodes, based on prokaryotic retrons1, that are reverse transcribed into DNA and integrated into the genome using the CRISPR-Cas system2. The unidirectional integration of barcodes by CRISPR integrases enables reconstruction of transcriptional event timing based on a physical record through simple, logical rules rather than relying on pretrained classifiers or post hoc inferential methods. For disambiguation in the field, we will refer to this system as a Retro-Cascorder.


Assuntos
Sistemas CRISPR-Cas , DNA , Edição de Genes , Expressão Gênica , Armazenamento e Recuperação da Informação , RNA , Transcrição Reversa , Sistemas CRISPR-Cas/genética , DNA/biossíntese , DNA/genética , Edição de Genes/métodos , Genoma/genética , Armazenamento e Recuperação da Informação/métodos , Integrases/metabolismo , Células Procarióticas/metabolismo , RNA/genética , Fatores de Tempo
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