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1.
Mol Cytogenet ; 17(1): 15, 2024 Jul 12.
Article in English | MEDLINE | ID: mdl-38992676

ABSTRACT

BACKGROUND: Mesomelia-Synostoses Syndrome (MSS)(OMIM 600,383) is a rare autosomal dominant disorder characterized by mesomelic limb shortening, acral synostoses and multiple congenital malformations which is described as a contiguous deletion syndrome involving the two genes SULF1 and SLCO5A1. The study of apparently balanced chromosomal rearrangements (BCRs) is a cytogenetic strategy used to identify candidate genes associated with Mendelian diseases or abnormal phenotypes. With the improved development of genomic technologies, new methods refine this search, allowing better delineation of breakpoints as well as more accurate genotype-phenotype correlation. CASE PRESENTATION: We present a boy with a global development deficit, delayed speech development and an ASD (Asperger) family history, with an apparently balanced "de novo" reciprocal translocation [t(1;8)(p32.2;q13)dn]. The cytogenetic molecular study identified a likely pathogenic deletion of 21 kb in the 15q12 region, while mate pair sequencing identified gene-truncations at both the 1p32.2 and 8q13 translocation breakpoints. CONCLUSIONS: The identification of a pathogenic alteration on 15q12 involving GABRA5 was likely the main cause of the ASD-phenotype. Importantly, the chr8 translocation breakpoint truncating SLCO5A1 exclude SLCO5A1 as a candidate for MSS, leaving SULF1 as the primary candidate. However, the deletions observed in MSS remove a topological associated domain (TAD) boundary separating SULF1 and SLCO5A1. Hence, Mesomelia-Synostoses syndrome is either caused by haploinsufficiency of SULF1 or ectopic enhancer effects where skeletal/chrondrogenic SULF1 enhancers drive excopic expression of developmental genes in adjacent TADs including PRDM14, NCOA2 and/or EYA1.

2.
Front Genet ; 15: 1384167, 2024.
Article in English | MEDLINE | ID: mdl-38706797

ABSTRACT

Background: Cis-regulatory elements (CREs) play crucial roles in regulating gene expression during erythroid cell differentiation. Genome-wide erythroid-specific CREs have not been characterized in chicken erythroid cells, which is an organism model used to study epigenetic regulation during erythropoiesis. Methods: Analysis of public genome-wide accessibility (ATAC-seq) maps, along with transcription factor (TF) motif analysis, CTCF, and RNA Pol II occupancy, as well as transcriptome analysis in fibroblasts and erythroid HD3 cells, were used to characterize erythroid-specific CREs. An α-globin CRE was identified, and its regulatory activity was validated in vitro and in vivo by luciferase activity and genome-editing assays in HD3 cells, respectively. Additionally, circular chromosome conformation capture (UMI-4C) assays were used to distinguish its role in structuring the α-globin domain in erythroid chicken cells. Results: Erythroid-specific CREs displayed occupancy by erythroid TF binding motifs, CTCF, and RNA Pol II, as well as an association with genes involved in hematopoiesis and cell differentiation. An α-globin CRE, referred to as CRE-2, was identified as exhibiting enhancer activity over αD and αA genes in vitro and in vivo. Induction of terminal erythroid differentiation showed that α-globin CRE-2 is required for the induction of αD and αA. Analysis of TF binding motifs at α-globin CRE-2 shows apparent regulation mediated by GATA-1, YY1, and CTCF binding. Conclusion: Our findings demonstrate that cell-specific CREs constitute a key mechanism that contributes to the fine-tuning gene regulation of erythroid cell differentiation and provide insights into the annotation and characterization of CREs in chicken cells.

3.
Front Cell Dev Biol ; 12: 1324584, 2024.
Article in English | MEDLINE | ID: mdl-38655067

ABSTRACT

ASCL1 is a transcription factor that directs neural progenitors towards lineage differentiation. Although many of the molecular mechanisms underlying its action have been described, several of its targets remain unidentified. We identified in the chick genome a putative enhancer (cE1) upstream of the transcription factor Scratch2 (Scrt2) locus with a predicted heterodimerization motif for ASCL1 and POU3F2. In this study, we investigated the role of ASCL1 and this enhancer in regulating the expression of the Scrt2 in the embryonic spinal cord. We confirmed that cE1 region interacted with the Scrt2 promoter. cE1 was sufficient to mediate ASCL1-driven expression in the neural tube through the heterodimerization sites. Moreover, Scrt2 expression was inhibited when we removed cE1 from the genome. These findings strongly indicate that ASCL1 regulates Scrt2 transcription in the neural tube through cE1.

4.
Proc Natl Acad Sci U S A ; 121(18): e2322692121, 2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38652744

ABSTRACT

Food intake and energy balance are tightly regulated by a group of hypothalamic arcuate neurons expressing the proopiomelanocortin (POMC) gene. In mammals, arcuate-specific POMC expression is driven by two cis-acting transcriptional enhancers known as nPE1 and nPE2. Because mutant mice lacking these two enhancers still showed hypothalamic Pomc mRNA, we searched for additional elements contributing to arcuate Pomc expression. By combining molecular evolution with reporter gene expression in transgenic zebrafish and mice, here, we identified a mammalian arcuate-specific Pomc enhancer that we named nPE3, carrying several binding sites also present in nPE1 and nPE2 for transcription factors known to activate neuronal Pomc expression, such as ISL1, NKX2.1, and ERα. We found that nPE3 originated in the lineage leading to placental mammals and remained under purifying selection in all mammalian orders, although it was lost in Simiiformes (monkeys, apes, and humans) following a unique segmental deletion event. Interestingly, ablation of nPE3 from the mouse genome led to a drastic reduction (>70%) in hypothalamic Pomc mRNA during development and only moderate (<33%) in adult mice. Comparison between double (nPE1 and nPE2) and triple (nPE1, nPE2, and nPE3) enhancer mutants revealed the relative contribution of nPE3 to hypothalamic Pomc expression and its importance in the control of food intake and adiposity in male and female mice. Altogether, these results demonstrate that nPE3 integrates a tripartite cluster of partially redundant enhancers that originated upon a triple convergent evolutionary process in mammals and that is critical for hypothalamic Pomc expression and body weight homeostasis.


Subject(s)
Body Weight , Eating , Enhancer Elements, Genetic , Hypothalamus , Pro-Opiomelanocortin , Zebrafish , Animals , Pro-Opiomelanocortin/metabolism , Pro-Opiomelanocortin/genetics , Mice , Hypothalamus/metabolism , Eating/genetics , Eating/physiology , Zebrafish/genetics , Zebrafish/metabolism , Female , Male , Mice, Transgenic , Humans , Transcription Factors/metabolism , Transcription Factors/genetics , Mammals/metabolism , Mammals/genetics
5.
Drug Deliv Transl Res ; 14(1): 103-115, 2024 Jan.
Article in English | MEDLINE | ID: mdl-37555906

ABSTRACT

This study aims to investigate the effect of the preparation of solid dispersions using supercritical CO2 (scCO2) on the physicochemical properties and the performance of supramolecular gels based on polymer-cyclodextrin (CD) interactions (named poly(pseudo)rotaxanes, PPR) envisaging a transdermal administration. Solid dispersions containing Soluplus®, the antihypertensive drug carvedilol (CAR), and CD (αCD or HPßCD) were prepared and characterized by HPLC, XRPD, FTIR, and DSC. PPRs prepared from solid dispersions (SCF gels) and the corresponding physical mixtures (PM gels) were analyzed regarding rheology, morphology, in vitro drug diffusion, and ex vivo drug skin permeation. The application of scCO2 led to the loss of the crystalline lattice of CAR while preserving its chemical identity. On the contrary, αCD crystals were still present in the SCF solid dispersions. SCF gels were more uniform than their corresponding PM, and the supercritical treatment resulted in changes in the rheological behavior, reducing the viscosity. CAR in vitro diffusion was significantly higher (p < 0.05) for the αCD-based SCF gel than its corresponding PM gel. Drug skin permeation showed a significant increase in drug flux from CD-based SCF gels (containing αCD or HPßCD) compared to corresponding PM gels. Additionally, the pretreatment of the skin with αCD exhibited increased CAR permeation, suggesting an interaction between αCD and the skin membrane. Results evidenced that SCF processing decisively modified the properties of the supramolecular gels, particularly those prepared with αCD.


Subject(s)
Cyclodextrins , Rotaxanes , Cyclodextrins/chemistry , Rotaxanes/chemistry , Administration, Cutaneous , 2-Hydroxypropyl-beta-cyclodextrin , Carvedilol , Gels/chemistry
6.
Clin Transl Oncol ; 26(4): 891-904, 2024 Apr.
Article in English | MEDLINE | ID: mdl-37697139

ABSTRACT

BACKGROUND: Recently, enhancer RNAs (eRNAs) have garnered attention as pivotal biomarkers for the onset and progression of cancer. However, the landscape of eRNAs and the implications of eRNA-based molecular subtypes in stage II/III colorectal cancer (CRC) remain largely unexplored. METHODS: Comprehensive profiling of eRNAs was conducted on a public stage II/III CRC cohort with total RNA-seq data. We used unsupervised clustering of prognostic eRNAs to establish an eRNA-based subtyping system. Further evaluations included molecular characteristics, immune infiltration, clinical outcomes, and drug responses. Finally, we validated the eRNA-based subtyping system in The Cancer Genome Atlas (TCGA) CRC cohort. RESULTS: We identified a total of 6453 expressed eRNAs, among which 237 were prognostic. A global upregulation of eRNAs was observed in microsatellite-stable (MSS) CRCs when compared to microsatellite instability-high (MSI-H) CRCs. Through consensus clustering, two novel molecular subtypes, termed Cluster 1(C1) and Cluster 2(C2), were further identified. C1, associated with the activation of epithelial-mesenchymal transition (EMT), hypoxia, and KRAS signaling pathways, showed poorer prognosis. C2, correlated with the canonical CRC subtype, exhibited superior survival outcomes. In addition, C1 showed enrichment with immune infiltration and more sensitivity to immune checkpoint inhibitors. CONCLUSION: Our study unravels the molecular heterogeneity of stage II/III CRC at the eRNA level and highlights the potential applications of the novel eRNA-based subtyping system in predicting prognosis and guiding immunotherapy.


Subject(s)
Colorectal Neoplasms , Enhancer RNAs , Humans , Prognosis , Colorectal Neoplasms/genetics , Colorectal Neoplasms/therapy , Colorectal Neoplasms/metabolism , Microsatellite Instability , Immunotherapy
7.
Braz. oral res. (Online) ; 38: e018, 2024. tab, graf
Article in English | LILACS-Express | LILACS, BBO - Dentistry | ID: biblio-1550152

ABSTRACT

Abstract The aim of this study was to evaluate the expression of the EZH2 protein and describe the clinical and microscopic characteristics of adenoid cystic carcinoma (ACC) and pleomorphic adenoma (PA). The study included 16 ACC cases and 12 PA. All ACC and PA cases were positive for EZH2 and the ACC samples showed significantly higher EZH2 expression. The clinical and microscopic covariates were described in relation to EZH2 staining in ACC samples. The highest mean values of EZH2 were observed in cases with local metastasis, recurrence, perineural invasion, and predominantly cribriform growth pattern without solid areas. EZH2 is a potential marker of malignancy.

8.
Int J Pharm ; 651: 123734, 2024 Feb 15.
Article in English | MEDLINE | ID: mdl-38142017

ABSTRACT

The present investigation was focused on the development of Soluplus®-based nanomicelles (NMs) (10 % w/v) loaded with Efavirenz (EFV) (5 mg/mL) and Curcumin (natural bio-enhancer) (CUR) (5, 10 and 15 mg/mL) to improve the oral bioavalability of EFV. Micellar formulations were obtained employing an acetone-diffusion technique. Apparent aqueous solubility was increased up to ∼1250-fold and 25,000-fold for EFV and CUR, respectively. Drug-loaded nanoformulations showed an excellent colloidal stability with unimodal size distribution and PDI values < 0.30. In vitro drug release was 41.5 % (EFV) and 2.6 % (CUR) from EFV-CUR-NMs over 6 h in simulated gastrointestinal fluids. EFV-CUR-loaded NMs resulted as safe nanoformulations according to the in vitro cytocompatibility assays in Caco-2 cells. Furthermore, CUR bio-enhancer activity was demonstrated for those nanoformulations. A CUR concentration of 15 mg/mL produced a significant (p < 0.05) increment (2.64-fold) of relative EFV oral bioavailability. Finally, the active role of the lymphatic system in the absorption process of EFV, after its oral administration was assessed in a comparative pharmacokinetic study in presence and absence of cycloheximide, a lymphatic transport inhibitor. Overall our EFV-CUR-NMs denoted their potential as a novel nanotechnological platform, representing a step towards an optimized "nano-sized" therapy for AIDS patients.


Subject(s)
Alkynes , Curcumin , Cyclopropanes , Humans , Caco-2 Cells , Biological Availability , Benzoxazines , Solubility , Micelles , Drug Carriers , Administration, Oral , Particle Size
9.
Fish Physiol Biochem ; 49(3): 487-500, 2023 Jun.
Article in English | MEDLINE | ID: mdl-37126120

ABSTRACT

Gamete production is a fundamental process for reproduction; however, exposure to stress, such as increased environmental temperature, can decrease or even interrupt this process, affecting fertility. Thus, the survival of spermatogonial stem cells (SSCs) is crucial for the recovery of spermatogenesis upon stressful situations. Here, we show that the Notch pathway is implicated in such survival, by protecting the SSCs against thermal stress. First, we corroborated the impairment of spermatogenesis under heat stress in medaka, observing an arrest in metaphase I at 10 days of heat treatment, an increase in the number of spermatocytes, and downregulation of ndrg1b and sycp3. In addition, at 30 days of treatment, an interruption of spermatogenesis was observed with a strong loss of spermatocytes and spermatids. Then, the exposure of adult males to thermal stress condition induced apoptosis mainly in spermatogenic and supporting somatic cells, with the exception of the germinal region, where SSCs are located. Concomitantly, the Notch pathway-related genes were upregulated, including the ligands (dll4, jag1-2) and receptors (notch1a-3). Moreover, during thermal stress presenilin enhancer-2 (pen-2), the catalytic subunit of γ-secretase complex of the Notch pathway was restricted to the germinal region of the medaka testis, observed in somatic cells surrounding type A spermatogonia (SGa). The importance of Notch pathway was further supported by an ex vivo approach, in which the inhibition of this pathway activity induced a loss of SSCs. Overall, this study supports the importance of Notch pathways for the protection of SSCs under chronic thermal stress.


Subject(s)
Oryzias , Male , Animals , Cell Differentiation , Testis/metabolism , Spermatogenesis/genetics , Spermatogonia/physiology , Stem Cells , Heat-Shock Response
10.
Antioxidants (Basel) ; 12(5)2023 May 03.
Article in English | MEDLINE | ID: mdl-37237903

ABSTRACT

Tetrahydrobiopterin (BH4) is an endogenous cofactor for some enzymatic conversions of essential biomolecules, including nitric oxide, and monoamine neurotransmitters, and for the metabolism of phenylalanine and lipid esters. Over the last decade, BH4 metabolism has emerged as a promising metabolic target for negatively modulating toxic pathways that may result in cell death. Strong preclinical evidence has shown that BH4 metabolism has multiple biological roles beyond its traditional cofactor activity. We have shown that BH4 supports essential pathways, e.g., to generate energy, to enhance the antioxidant resistance of cells against stressful conditions, and to protect from sustained inflammation, among others. Therefore, BH4 should not be understood solely as an enzyme cofactor, but should instead be depicted as a cytoprotective pathway that is finely regulated by the interaction of three different metabolic pathways, thus assuring specific intracellular concentrations. Here, we bring state-of-the-art information about the dependency of mitochondrial activity upon the availability of BH4, as well as the cytoprotective pathways that are enhanced after BH4 exposure. We also bring evidence about the potential use of BH4 as a new pharmacological option for diseases in which mitochondrial disfunction has been implicated, including chronic metabolic disorders, neurodegenerative diseases, and primary mitochondriopathies.

11.
J Exp Biol ; 226(10)2023 05 15.
Article in English | MEDLINE | ID: mdl-37078652

ABSTRACT

Scaling between specific organs and overall body size has long fascinated biologists, being a primary mechanism by which organ shapes evolve. Yet, the genetic mechanisms that underlie the evolution of scaling relationships remain elusive. Here, we compared wing and fore tibia lengths (the latter as a proxy of body size) in Drosophila melanogaster, Drosophila simulans, Drosophila ananassae and Drosophila virilis, and show that the first three of these species have roughly a similar wing-to-tibia scaling behavior. In contrast, D. virilis exhibits much smaller wings relative to their body size compared with the other species and this is reflected in the intercept of the wing-to-tibia allometry. We then asked whether the evolution of this relationship could be explained by changes in a specific cis-regulatory region or enhancer that drives expression of the wing selector gene, vestigial (vg), whose function is broadly conserved in insects and contributes to wing size. To test this hypothesis directly, we used CRISPR/Cas9 to replace the DNA sequence of the predicted Quadrant Enhancer (vgQE) from D. virilis for the corresponding vgQE sequence in the genome of D. melanogaster. Strikingly, we discovered that D. melanogaster flies carrying the D. virilis vgQE sequence have wings that are significantly smaller with respect to controls, partially shifting the intercept of the wing-to-tibia scaling relationship towards that observed in D. virilis. We conclude that a single cis-regulatory element in D. virilis contributes to constraining wing size in this species, supporting the hypothesis that scaling could evolve through genetic variations in cis-regulatory elements.


Subject(s)
Drosophila Proteins , Drosophila , Animals , Drosophila/genetics , Drosophila/metabolism , Drosophila melanogaster/genetics , Drosophila melanogaster/metabolism , Drosophila Proteins/genetics , Drosophila Proteins/metabolism , Base Sequence , Enhancer Elements, Genetic , Gene Expression Regulation, Developmental , Wings, Animal
12.
Heliyon ; 9(2): e12120, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36793975

ABSTRACT

Research reports reveal the importance of applying various substances to enhance extra-heavy crude oil pipeline transportation. During the crude oil conduction process, shearing occurs in the equipment and pipe accessories, producing a water-in-crude emulsion associated with forming a rigid film by adsorbing natural surfactant molecules in the droplets water, leading to increased Viscosity. This study presents the effect of a flow enhancer (FE) on the behavior of the Viscosity of an extra heavy crude oil (EHCO) and in emulsions formed with 5% and 10% water (W). The results revealed the effectiveness of the 1%, 3%, and 5% flow enhancer in lowering the Viscosity and presenting a Newtonian flow behavior which will help reduce the cost of heat treatment during the transportation of crude oil through the pipeline.

13.
Rev. Assoc. Med. Bras. (1992, Impr.) ; Rev. Assoc. Med. Bras. (1992, Impr.);69(1): 153-158, Jan. 2023. tab, graf
Article in English | LILACS-Express | LILACS | ID: biblio-1422597

ABSTRACT

SUMMARY OBJECTIVE: Breast cancer is the most common malignancy in women. In the treatment of these patients, pathological complete response is defined as the absence of invasive cancer in breast or lymph node tissue after the completion of neoadjuvant chemotherapy. In this study, we aimed to investigate the relationship of enhancer of zeste homolog 2 and mucin 1 expressions with pathological complete response in patients with breast cancer receiving neoadjuvant chemotherapy. METHODS: A total of 151 patients were included in the study. Enhancer of zeste homolog 2 and mucin 1 expressions were evaluated in the biopsy materials pre-neoadjuvant chemotherapy and post-neoadjuvant chemotherapy surgical material, and their relationship with pathological complete response was investigated. RESULTS: The pathological complete response rates were significantly higher among the hormone receptor-negative patients, those with a high Ki-67 score, and patients with HER2-positive. Higher pathological complete response rates were obtained from patients with enhancer of zeste homolog 2 expression positivity pre-neoadjuvant chemotherapy. In addition, after neoadjuvant chemotherapy, enhancer of zeste homolog 2 expression was found to be completely negative in materials with pathological complete response; that is, in breast tissues considered to be tumor-free. While there was no significant relationship between mucin 1 expression and pathological complete response pre-neoadjuvant chemotherapy, mucin 1 expression was determined to significantly differ between the tissues with and without pathological complete response among the surgical materials examined. CONCLUSION: In our study investigating the relationship between enhancer of zeste homolog 2 and mucin 1 expression and pathological complete response in patients who received neoadjuvant chemotherapy, we found that enhancer of zeste homolog 2 expression could be used as a predictive marker for pathological complete response. However, mucin 1 expression was not associated with pathological complete response.

14.
J Exp Zool B Mol Dev Evol ; 340(8): 496-508, 2023 12.
Article in English | MEDLINE | ID: mdl-33544406

ABSTRACT

Strict interpretations of the Dollo's Law lead to postulation that trait loss is irreversible and organisms never recover ancestral phenotypes. Dollo, however, admitted the possibility of reversals in trait loss when predicted differences between reversed (derived) and ancestral forms. Phenotypic signatures from reversals are expected, as the historical context of a reversal in trait loss differs from the initial setting where the trait originally evolved. This article combines morphological and molecular information for Bachia scolecoides to discuss phenotypic and genetic patterns established during processes that reversed digit loss in Gymnophthalmidae (also termed microteiid lizards). Results suggest that pathways leading to the derived tetradactyl state of B. scolecoides comprise particularities in their origin and associated processes. Autopodial bones of B. scolecoides lack digit identity, and muscle anatomy is very similar between manus and pes. Gymnophthalmidae sequence patterns in the limb-specific sonic hedgehog enhancer (ZRS) suggest that regulation of shh expression did not degenerate in Bachia, given the prediction of similar motifs despite mutations specific to Bachia. Persistence of developmental mechanisms might explain intermittent character expression leading to reversals of digit loss, as ZRS signaling pathways remain active during the development of at least one pair of appendices in Bachia, especially if some precursors persisted at early stages. Patterns of ZRS sequences suggest that irreversibility of trait loss might be lineage-specific (restricted to Gymnophthalmini) and contingent to the type of signature established. These results provide insights regarding possible mechanisms that may allow reactivation of developmental programs in specific regions of the embryo.


Subject(s)
Hedgehog Proteins , Lizards , Animals , Hedgehog Proteins/genetics , Lizards/anatomy & histology , Extremities , Muscles , Forelimb/anatomy & histology
15.
Food Chem (Oxf) ; 6: 100155, 2023 Jul 30.
Article in English | MEDLINE | ID: mdl-36582744

ABSTRACT

Chronic Non-Communicable Diseases (NCDs) have been considered a global health problem, characterized as diseases of multiple factors, which are developed throughout life, and regardless of genetics as a risk factor of important relevance, the increase in mortality attributed to the disease to environmental factors and the lifestyle one leads. Although the reactive species (ROS/RNS) are necessary for several physiological processes, their overproduction is directly related to the pathogenesis and aggravation of NCDs. In contrast, dietary polyphenols have been widely associated with minimizing oxidative stress and inflammation. In addition to their antioxidant power, polyphenols have also drawn attention for being able to modulate both gene expression and modify epigenetic alterations, suggesting an essential involvement in the prevention and/or development of some pathologies. Therefore, this review briefly explained the mechanisms in the development of some NCDs, followed by a summary of some evidence related to the interaction of polyphenols in oxidative stress, as well as the modulation of epigenetic mechanisms involved in the management of NCDs.

16.
Pharmaceutics ; 14(11)2022 Nov 11.
Article in English | MEDLINE | ID: mdl-36432637

ABSTRACT

Transdermal administration of molecules across the skin has gained interest because it can be considered a non-invasive route compared with traditional ones. However, going through the skin is challenging due to the presence of the stratum corneum, the main barrier of substances. For this reason, the goal of this research was the combination of omega-3 (ω-3) and a dextran sulfate assembly in a nanostructure form, which allows passage through the skin and improves the bioavailability and the therapeutic profiles of active molecules, such as imiquimod. Here we report a new colloidal system, named dextran nanocapsules, with ω-3 in its nucleus and a coat made of dextran sulfate with a size ~150 nm, monomodal distribution, and negative zeta potential (~-33 mV). This nanosystem encapsulates imiquimod with high efficacy (~86%) and can release it in a controlled fashion following Korsmeyer-Peppas kinetics. This formulation is stable under storage and physiological conditions. Furthermore, a freeze-dried product could be produced with different cryoprotectants and presents a good security profile in the HaCaT cell line. Ex vivo assays with newborn pig skin showed that dextran nanocapsules promote transdermal delivery and retention 10 times higher than non-encapsulated imiquimod. These promising results make this nanosystem an efficient vehicle for imiquimod transdermal delivery.

17.
Proc Biol Sci ; 289(1981): 20220841, 2022 08 31.
Article in English | MEDLINE | ID: mdl-35975445

ABSTRACT

Developmental pathways encompass transcription factors and cis-regulatory elements that interact as transcription factor-regulatory element (TF-RE) units. Independent origins of similar phenotypes likely involve changes in different parts of these units, a hypothesis promisingly tested addressing the evolution of the rib-associated lumbar (RAL) morphotype that characterizes emblematic animals such as snakes and elephants. Previous investigation in these lineages identified a polymorphism in the Homology region 1 [H1] enhancer of the Myogenic factor-5 [Myf5], which interacts with HOX10 proteins to modulate rib development. Here we address the evolution of TF-RE units focusing on independent origins of RAL morphotypes. We compiled an extensive database for H1-Myf5 and HOX10 sequences with two goals: (i) evaluate if the enhancer polymorphism is present in amphibians exhibiting the RAL morphotype and (ii) test a hypothesis of enhanced evolutionary flexibility mediated by TF-RE units, according to which independent origins of the RAL morphotype might involve changes in either component of the interaction unit. We identified the H1-Myf5 polymorphism in lineages that diverged around 340 Ma, including Lissamphibia. Independent origins of the RAL morphotype in Tetrapoda involved sequence variation in either component of the TF-RE unit, confirming that different changes may similarly affect the phenotypic outcome of a given developmental pathway.


Subject(s)
Regulatory Sequences, Nucleic Acid , Transcription Factors , Amphibians/metabolism , Animals , Myogenic Regulatory Factor 5/genetics , Myogenic Regulatory Factor 5/metabolism , Snakes/genetics , Transcription Factors/genetics , Transcription Factors/metabolism
18.
Genome Biol Evol ; 14(6)2022 05 31.
Article in English | MEDLINE | ID: mdl-35552697

ABSTRACT

Enhancers are regulatory elements of genomes that determine spatio-temporal patterns of gene expression. The human genome contains a vast number of enhancers, which largely outnumber protein-coding genes. Historically, enhancers have been regarded as highly tissue-specific. However, recent evidence has demonstrated that many enhancers are pleiotropic, with activity in multiple developmental contexts. Yet, the extent and impact of pleiotropy remain largely unexplored. In this study we analyzed active enhancers across human organs based on the analysis of both eRNA transcription (FANTOM5 consortium data sets) and chromatin architecture (ENCODE consortium data sets). We show that pleiotropic enhancers are pervasive in the human genome and that most enhancers active in a particular organ are also active in other organs. In addition, our analysis suggests that the proportion of context-specific enhancers of a given organ is explained, at least in part, by the proportion of context-specific genes in that same organ. The notion that such a high proportion of human enhancers can be pleiotropic suggests that small regions of regulatory DNA contain abundant regulatory information and that these regions evolve under important evolutionary constraints.


Subject(s)
Enhancer Elements, Genetic , Genome, Human , Biological Evolution , Chromatin/genetics , Humans
19.
Belo Horizonte; s.n; 2022. 53 p. ilus, tab.
Thesis in Portuguese | LILACS, BBO - Dentistry | ID: biblio-1424987

ABSTRACT

As neoplasias de glândulas salivares apresentam comportamentos diferenciados, que não seguem os padrões clássicos das neoplasias benignas e malignas. A raridade de algumas destas lesões dificulta ainda mais o entendimento dos mecanismos envolvidos na etiopatogenia. Marcadores moleculares como a proteína EZH2 têm sido utilizados na investigação de alterações epigenéticas em diferentes neoplasias, auxiliando na definição do diagnóstico e prognóstico das lesões. O objetivo do presente trabalho é avaliar a expressão da proteína EZH2 e descrever as características clínicas e microscópicas de amostras de carcinoma adenoide cístico (CAC) e adenoma pleomórfico (AP) com ênfase na importância da definição da malignidade da lesão. A análise dos cortes microscópicos corados em Hematoxilina e Eosina dos casos de Adenoma pleomórfico mostraram células epiteliais e mioepiteliais glandulares dispostas em lençóis e estruturas ductiformes em meio a estroma variável. Os casos de Carcinoma adenoide cístico mostraram três padrões distintos de crescimento incluindo formações tubulares, cribriformes e sólidas. Todos os casos de AP e CAC foram positivos para reação imuno-histoquímica para EZH2. As amostras de CAC apresentaram expressão de EZH2 significativamente maior comparado ao AP. As covariáveis metástase em linfonodos, recorrência, padrão histológico, presença de áreas sólidas e invasão perineural foram descritas em relação à marcação de EZH2 em amostras de CAC. Dessa forma, os resultados do estudo melhoram o entendimento das características clínicas e histológicas do CAC, assim como sobre o comportamento das lesões. Além disso, a análise mostra que o EZH2 é um potencial marcador de malignidade e ressalta a importância da validação de marcadores moleculares de alterações epigenéticas.


Salivary gland neoplasms present different behaviors, which do not follow the classic patterns of benign and malignant neoplasms. The rarity of some of these lesions makes it even more difficult to understand the mechanisms involved in the etiopathogenesis. Molecular markers such as the EZH2 protein have been used to investigate epigenetic changes in different neoplasms, helping to define the diagnosis and prognosis of the lesions. The aim of the study was to evaluate the expression of the EZH2 protein and to describe the clinical and microscopic characteristics of adenoid cystic carcinoma (ACC) and pleomorphic adenoma (PA) which emphasizes the importance of defining the malignancy of the neoplasm. Histopathological analysis of PA cases showed myoepithelial and glandular epithelial cells arranged as duct-like structures and sheets intermingled in the variable stroma and ACC cases showed the three growth patterns, tubular, cribriform and solid forms. All ACC and PA cases were positive for EZH2, with diffuse nuclear staining in neoplastic cells. The ACC samples showed significantly higher EZH2 expression compared to the PA. The covariables nodal metastasis, recurrence, growth pattern, presence of solid areas and perineural invasion have been described in relation to EZH2 staining in ACC samples. The results of the study improve the understanding of the clinical and histological characteristics of ACC, as well as on the behavior of lesions. In addition, the analysis showed that EZH2 is a potential marker of malignancy and highlights the importance of validating molecular markers of epigenetic alterations.


Subject(s)
Salivary Gland Neoplasms , Immunohistochemistry , Carcinoma, Adenoid Cystic , Adenoma, Pleomorphic , Epigenomics , Enhancer of Zeste Homolog 2 Protein
20.
Braz. J. Pharm. Sci. (Online) ; 58: e20486, 2022. tab
Article in English | LILACS | ID: biblio-1403694

ABSTRACT

Abstract In the present research investigation, various concentrations of hydro-alcoholic extract of Saraca asoca (Roxb.) De Wilde (family: Caesalpinaceae) dried bark and carbopol polymer at different temperature ranges were optimized for the preparation of gel formulation. Natural penetration enhancers, v.i.z., eucalyptus oil and peppermint oil were incorporated separately in the extract based gel formulations to study the rate of drug permeation across egg membrane, using franz diffusion cell. In vitro anti-arthritis potential of the formulations was also studied using inhibition of albumin denaturation, antiproteinase activity and membrane stabilization method. As per the results of current study, it is established that S. asoca dried bark hydroalcoholic extract based gel prepared using peppermint oil as penetration enhancer exhibited good permeation rate of 8.48% at the end of 3 h. The percentage inhibition of proteins by antiproteinase method at concentration of 50 µg/ml was 50.01±1.00% which was close to 53.92±0.99% as shown by the standard drug, Diclofenac. Also, the percent protein inhibition determined using membrane stabilization method was found to be 49.70±1.00%, however, it was 63.32±0.94% for the standard drug, Diclofenac. Hence, it is concluded that peppermint oil may act as a good candidate for the preparation of potent anti-rheumatic gel preparations.


Subject(s)
Plant Oils/analysis , Pharmaceutical Preparations/analysis , Joanesia asoca/analysis , Mentha piperita/anatomy & histology , Hydroalcoholic Solution , Eucalyptus Oil/analysis , Arthritis, Rheumatoid/pathology , In Vitro Techniques/methods , Plant Extracts/agonists
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