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2.
Braz. j. biol ; 83: e247433, 2023. tab, graf
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1339336

RESUMO

Abstract The life cycle of stink bug, Glyphepomis dubia and the development of two egg parasitoids (Telenomus podisi and Trissolcus basalis) were studied at the Federal University of Maranhão, at 26 ± 2oC, relative humidity (RH) of 60 ± 10% and 12h photophase. Individuals used in the study were collected from seven rice fields located around the municipality of Arari, Maranhão, Brazil, and maintained in greenhouse and laboratory for the life cycle studies. From egg to adult, G. dubia took 35.2 days to complete the life cycle. The oviposition period was 37 days, with egg masses of about 12 eggs each and viability of 93.1%. Longevity was 53 and 65 days for females and males, respectively. The egg parasitoids Te. podisi and Tr. basalis parasitized and developed in G. dubia eggs; however, the biological characteristics of Tr. basalis were affected. Emergence of the parasitoids was higher for Te. podisi (83.5%) compared to the records for Tr. basalis (50.4%). Therefore, G. dubia may potentially achieve a pest status and Te. podisi is a promising biological control agent for G. dubia management in Brazil due to its higher longevity and better reproductive parameters.


Resumo O ciclo de vida do percevejo, Glyphepomis dubia e a biologia de dois parasitoides de ovos (Telenomus podisi e Trissolcus basalis) foram estudados na Universidade Federal do Maranhão, a 26 ± 2oC, umidade relativa (UR) de 60 ± 10% e fotofase de 12h. Sete indivíduos de G. dubia foram coletados em lavoura de arroz localizada no município de Arari, Maranhão, Brasil e mantidos em casa de vegetação e laboratório para estudos de ciclo de vida. Do ovo ao adulto, G. dubia levou 35.2 dias para completar o ciclo de vida. O período de oviposição foi de 37 dias com massas de ovos com cerca de 12 ovos/massa e viabilidade de 93.1%. A longevidade foi de 53 e 65 dias, respectivamente, para fêmeas e machos. Os parasitoides de ovos, Te. podisi e Tr. basalis parasitaram e se desenvolveram em ovos de G. dubia, no entanto as características biológicas de Tr. basalis foi afetada. A emergência dos parasitoides foi maior para Te. podisi (83.5%) em comparação com o registrado para Tr. basalis (50.4%). Portanto, G. dubia poderá apresentar potencial para atingir o status de praga e Te. podisi é um promissor agente de controle biológico para ser utilizado no manejo de G. dubia no Brasil, pois apresentou maior longevidade e os melhores parâmetros reprodutivos.


Assuntos
Humanos , Animais , Oryza , Vespas , Heterópteros , Hemípteros , Himenópteros , Oviposição , Óvulo , Biologia
3.
Methods Mol Biol ; 2580: 25-49, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36374449

RESUMO

Thymic epithelial cells (TECs) make up the thymic microenvironments that support the generation of a functionally competent and self-tolerant T-cell repertoire. Cortical (c)TECs, present in the cortex, are essential for early thymocyte development including selection of thymocytes expressing functional TCRs (positive selection). Medullary (m)TECs, located in the medulla, play a key role in late thymocyte development, including depletion of self-reactive T cells (negative selection) and selection of regulatory T cells. In recent years, transcriptomic analysis by single-cell (sc)RNA sequencing (Seq) has revealed TEC heterogeneity previously masked by population-level RNA-Seq or phenotypic studies. We summarize the discoveries made possible by scRNA-Seq, including the identification of novel mTEC subsets, advances in understanding mTEC promiscuous gene expression, and TEC alterations from embryonic to adult stages. Whereas pseudotime analyses of scRNA-Seq data can suggest relationships between TEC subsets, experimental methods such as lineage tracing and reaggregate thymic organ culture (RTOC) are required to test these hypotheses. Lineage tracing - namely, of ß5t or Aire expressing cells - has exposed progenitor and parent-daughter cellular relationships within TEC.


Assuntos
Células Epiteliais , Timo , Animais , Camundongos , Diferenciação Celular/genética , Análise de Sequência de RNA , Biologia , Camundongos Endogâmicos C57BL , Linhagem da Célula/genética
4.
Methods Mol Biol ; 2567: 163-180, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36255701

RESUMO

The bone marrow (BM) has traditionally been a difficult tissue to access because it is embedded deep within the bone matrix. It is home to the hematopoietic stem cells (HSCs) that give rise to all blood cells in the body. It is also the site of origin for malignant blood cells such as leukemia and multiple myeloma, as well as a frequent site of metastasis for many solid tumors including prostate and breast cancer. The following chapter describes how laser micromachining of bone can be used to improve both optical and physical access to the BM. For example, laser thinning of the overlying bone can improve optical access, enabling deeper imaging into the BM as well as enhancing optical resolution by reducing scattering and aberration. Laser micromachining can also be used to provide physical access into the BM by creating access ports for micropipette insertion and delivery of cells to precise locations in the BM, as well as for the extraction of BM cells and interstitial fluid, all under image guidance. This chapter provides a detailed protocol for installing a laser-micromachining capability for users with an existing multiphoton microscope. Additionally, we briefly outline how such a system improves the optical resolution during imaging as well as its potential use to study injury response.


Assuntos
Medula Óssea , Microtecnologia , Masculino , Humanos , Medula Óssea/patologia , Células-Tronco Hematopoéticas , Células da Medula Óssea/fisiologia , Lasers , Biologia
5.
Methods Mol Biol ; 2562: 155-163, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36272073

RESUMO

The axolotl is a great model for studying cartilage, bone and joint regeneration, fracture healing, and evolution. Stainings such as Alcian Blue/Alizarin Red have become workhorses in skeletal analyses, but additional methods complement the detection of different skeletal matrices. Here we describe protocols for studying skeletal biology in axolotls, particularly Alcian Blue/Alizarin Red staining, microcomputed tomography (µCT) scan and live staining of calcified tissue. In addition, we describe a method for decalcification of skeletal elements to ease sectioning.


Assuntos
Ambystoma mexicanum , Biologia , Animais , Azul Alciano , Microtomografia por Raio-X , Coloração e Rotulagem
6.
Semin Cell Dev Biol ; 134: 59-68, 2023 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-35430142

RESUMO

Plant terrestrialization was a critical event for our planet. For the study of plant evolution, charophytes have received a great deal of attention because of their phylogenetic position. Among charophytes, the class Zygnematophyceae is the closest lineage to land plants. During sexual reproduction, they show isogamous conjugation by immotile gametes, which is characteristic of zygnematophycean algae. Here, we introduce the genera Mougeotia, Penium, and Closterium, which are representative model organisms of Zygnematophyceae in terms of chloroplast photorelocation movement, the cell wall, and sexual reproduction, respectively.


Assuntos
Plantas , Reprodução , Filogenia , Parede Celular , Biologia , Evolução Biológica
7.
Semin Cell Dev Biol ; 135: 93-101, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-35249811

RESUMO

Variants of the histone H2A occupy distinct locations in the genome. There is relatively little known about the mechanisms responsible for deposition of specific H2A variants. Notable exceptions are chromatin remodelers that control the dynamics of H2A.Z at promoters. Here we review the steps that identified the role of a specific class of chromatin remodelers, including LSH and DDM1 that deposit the variants macroH2A in mammals and H2A.W in plants, respectively. The function of these remodelers in heterochromatin is discussed together with their multiple roles in genome stability.


Assuntos
Heterocromatina , Histonas , Animais , Histonas/genética , Histonas/metabolismo , Heterocromatina/genética , Cromatina , Regiões Promotoras Genéticas , Mamíferos/genética , Biologia , Nucleossomos
8.
Life Sci Alliance ; 6(1)2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36283703

RESUMO

Insulin-induced GLUT4 translocation to the plasma membrane in muscle and adipocytes is crucial for whole-body glucose homeostasis. Currently, GLUT4 trafficking assays rely on overexpression of tagged GLUT4. Here we describe a high-content imaging platform for studying endogenous GLUT4 translocation in intact adipocytes. This method enables high fidelity analysis of GLUT4 responses to specific perturbations, multiplexing of other trafficking proteins and other features including lipid droplet morphology. Using this multiplexed approach we showed that Vps45 and Rab14 are selective regulators of GLUT4, but Trarg1, Stx6, Stx16, Tbc1d4 and Rab10 knockdown affected both GLUT4 and TfR translocation. Thus, GLUT4 and TfR translocation machinery likely have some overlap upon insulin-stimulation. In addition, we identified Kif13A, a Rab10 binding molecular motor, as a novel regulator of GLUT4 traffic. Finally, comparison of endogenous to overexpressed GLUT4 highlights that the endogenous GLUT4 methodology has an enhanced sensitivity to genetic perturbations and emphasises the advantage of studying endogenous protein trafficking for drug discovery and genetic analysis of insulin action in relevant cell types.


Assuntos
Adipócitos , Proteínas rab de Ligação ao GTP , Camundongos , Animais , Células 3T3-L1 , Proteínas rab de Ligação ao GTP/metabolismo , Adipócitos/metabolismo , Insulina/metabolismo , Transportador de Glucose Tipo 4/genética , Transportador de Glucose Tipo 4/metabolismo , Glucose/metabolismo , Biologia
10.
Int J Mol Sci ; 23(21)2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36362216

RESUMO

Proprotein convertase subtilisin/kexin 6 (PCSK6) is a secreted serine protease expressed in most major organs, where it cleaves a wide range of growth factors, signaling molecules, peptide hormones, proteolytic enzymes, and adhesion proteins. Studies in Pcsk6-deficient mice have demonstrated the importance of Pcsk6 in embryonic development, body axis specification, ovarian function, and extracellular matrix remodeling in articular cartilage. In the cardiovascular system, PCSK6 acts as a key modulator in heart formation, lipoprotein metabolism, body fluid homeostasis, cardiac repair, and vascular remodeling. To date, dysregulated PCSK6 expression or function has been implicated in major cardiovascular diseases, including atrial septal defects, hypertension, atherosclerosis, myocardial infarction, and cardiac aging. In this review, we describe biochemical characteristics and posttranslational modifications of PCSK6. Moreover, we discuss the role of PCSK6 and related molecular mechanisms in cardiovascular biology and disease.


Assuntos
Sistema Cardiovascular , Infarto do Miocárdio , Animais , Camundongos , Biologia , Sistema Cardiovascular/metabolismo , Pró-Proteína Convertases/genética , Pró-Proteína Convertases/metabolismo , Subtilisina
12.
Elife ; 112022 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-36355038

RESUMO

The dichotomy that separates prokaryotic from eukaryotic cells runs deep. The transition from pro- to eukaryote evolution is poorly understood due to a lack of reliable intermediate forms and definitions regarding the nature of the first host that could no longer be considered a prokaryote, the first eukaryotic common ancestor, FECA. The last eukaryotic common ancestor, LECA, was a complex cell that united all traits characterising eukaryotic biology including a mitochondrion. The role of the endosymbiotic organelle in this radical transition towards complex life forms is, however, sometimes questioned. In particular the discovery of the asgard archaea has stimulated discussions regarding the pre-endosymbiotic complexity of FECA. Here we review differences and similarities among models that view eukaryotic traits as isolated coincidental events in asgard archaeal evolution or, on the contrary, as a result of and in response to endosymbiosis. Inspecting eukaryotic traits from the perspective of the endosymbiont uncovers that eukaryotic cell biology can be explained as having evolved as a solution to housing a semi-autonomous organelle and why the addition of another endosymbiont, the plastid, added no extra compartments. Mitochondria provided the selective pressures for the origin (and continued maintenance) of eukaryotic cell complexity. Moreover, they also provided the energetic benefit throughout eukaryogenesis for evolving thousands of gene families unique to eukaryotes. Hence, a synthesis of the current data lets us conclude that traits such as the Golgi apparatus, the nucleus, autophagosomes, and meiosis and sex evolved as a response to the selective pressures an endosymbiont imposes.


Assuntos
Células Eucarióticas , Simbiose , Células Eucarióticas/fisiologia , Simbiose/genética , Evolução Biológica , Eucariotos/genética , Archaea/genética , Núcleo Celular , Meiose , Biologia , Filogenia
13.
PLoS One ; 17(11): e0277383, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36355764

RESUMO

The Mediterranean Sea is a renowned biodiversity hotspot influenced by multiple interacting ecological and human forces. A gap analysis on the biology of Mediterranean marine fishes was conducted in 2017, revealing the most studied species and biological characteristics, as well as identifying knowledge gaps and areas of potential future research. Here, we updated this gap analysis five years later by reviewing the literature containing information on the same eight biological characteristics, namely length-weight relationships, growth, maximum age, mortality, spawning, maturity, fecundity and diet, for the 722 fish species of the Mediterranean Sea. The results revealed a considerable knowledge gap as 37% of the species had no information for any of the studied characteristics, while 13% had information on only one characteristic. Out of all the biological characteristics, the smallest knowledge gap was found in the length-weight relationships (studied for 51% of the species, mainly in the eastern Mediterranean), while the least studied characteristic was mortality (studied for 10% of the species). The western and eastern Mediterranean Sea were leading forces in data collection exhibiting the narrowest gaps between current and desired knowledge. The most studied species across the entire region were the highly commercial European hake (Merluccius merluccius), red mullet (Mullus barbatus), European anchovy (Engraulis encrasicolus), European pilchard (Sardina pilchardus), common pandora (Pagellus erythrinus), and annular seabream (Diplodus annularis). The knowledge gap has shrunk by 6% during the last five years, with 40 new species having at least one study on their biology. Moreover, research has slightly shifted towards species that have been traditionally neglected, e.g., sharks, rays and chimaeras (chondrichthyans). It is recommended that research becomes less focused on commercial species and more targeted towards the identified gaps, vulnerable species (e.g., deep-sea species and chondrichthyans) and species that could potentially pose a threat (e.g., non-indigenous species) to the ecosystems of the everchanging Mediterranean Sea.


Assuntos
Gadiformes , Perciformes , Dourada , Animais , Humanos , Ecossistema , Peixes , Mar Mediterrâneo , Alimentos Marinhos/análise , Biologia
14.
Int J Mol Sci ; 23(21)2022 Oct 28.
Artigo em Inglês | MEDLINE | ID: mdl-36361856

RESUMO

The chemical element selenium (Se) is a nonmetal that is in trace amounts indispensable for normal cellular functioning. During pregnancy, a low Se status can increase the risk of oxidative stress. However, elevated concentrations of Se in the body can also cause oxidative stress. This study aimed to compare the effects of BSA-stabilized Se nanoparticles (SeNPs, Se0) (BSA-bovine serum albumin) and inorganic sodium selenite (NaSe, Se+4) supplementation on the histological structure of the placenta, oxidative stress parameters and the total placental Se concentration of Wistar rats during pregnancy. Pregnant females were randomized into four groups: (i) intact controls; (ii) controls that were dosed by daily oral gavage with 8.6% bovine serum albumin (BSA) and 0.125 M vit C; (iii) the SeNP group that was administered 0.5 mg of SeNPs stabilized with 8.6% BSA and 0.125 M vit C/kg bw/day by oral gavage dosing; (iv) the NaSe group, gavage dosed with 0.5 mg Na2SeO3/kg bw/day. The treatment of pregnant females started on gestational day one, lasted until day 20, and on day 21 of gestation, the fetuses with the placenta were removed from the uterus. Our findings show that the mode of action of equivalent concentrations of Se in SeNPs and NaSe depended on its redox state and chemical structure. Administration of SeNPs (Se0) increased fetal lethality and induced changes in the antioxidative defense parameters in the placenta. The accumulation of Se in the placenta was highest in SeNP-treated animals. All obtained data indicate an increased bioavailability of Se in its organic nano form and Se0 redox state in comparison to its inorganic sodium selenite form and Se+4 redox state.


Assuntos
Nanopartículas , Selênio , Animais , Feminino , Ratos , Gravidez , Selenito de Sódio/farmacologia , Selênio/química , Soroalbumina Bovina/farmacologia , Ratos Wistar , Placenta , Estresse Oxidativo , Oxirredução , Nanopartículas/química , Suplementos Nutricionais , Biologia
15.
Int J Mol Sci ; 23(21)2022 Nov 05.
Artigo em Inglês | MEDLINE | ID: mdl-36362366

RESUMO

Double-stranded RNA-binding proteins (dsRBPs) are major players in the regulation of gene expression patterns. Among them, Nuclear Factor 90 (NF90) has a plethora of well-known functions in viral infection, transcription, and translation as well as RNA stability and degradation. In addition, NF90 has been identified as a regulator of microRNA (miRNA) maturation by competing with Microprocessor for the binding of pri-miRNAs in the nucleus. NF90 was recently shown to control the biogenesis of a subset of human miRNAs, which ultimately influences, not only the abundance, but also the expression of the host gene and the fate of the mRNA target repertoire. Moreover, recent evidence suggests that NF90 is also involved in RNA-Induced Silencing Complex (RISC)-mediated silencing by binding to target mRNAs and controlling their translation and degradation. Here, we review the many, and growing, functions of NF90 in RNA biology, with a focus on the miRNA pathway and RISC-mediated gene silencing.


Assuntos
MicroRNAs , Proteínas do Fator Nuclear 90 , Humanos , Proteínas do Fator Nuclear 90/genética , Proteínas do Fator Nuclear 90/metabolismo , MicroRNAs/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Estabilidade de RNA , Biologia
17.
Hist Philos Life Sci ; 44(4): 54, 2022 Nov 03.
Artigo em Inglês | MEDLINE | ID: mdl-36326954

RESUMO

This paper examines the efforts in evolution research to understand form's structure that developed in Italy during the first half of the twentieth century. In particular, it analyzes how the organic approach in biology and the study of organic form merged in the morphological research agendas of Giuseppe Colosi (1892-1975) and Giuseppe Levi (1872-1965). These biologists sought to understand form's inner composition and structure. First, I will briefly outline the morphological practices and frameworks used to study form changes and structures in the early twentieth century. Second, I will discuss what the Italian biologist Antonio Pensa (1874-1970) called the morphological problem. Third, I will examine Colosi's response to the morphological problem. Fourth, I will analyze Levi's morphological research program. As a result, this paper paves the way for a more nuanced and varied picture of the so-called "organicism movement" in the first half of the twentieth century by calling attention to morphology as practiced in Italian-speaking biology. In fact, alongside dialectical materialism and holistic biology, two of the main strands within organicism, the architectural approach to evolution as practiced in Italy and elsewhere had a profound impact on twentieth- and twenty-first-century organicism specifically and on evolutionary biology generally.


Assuntos
Biologia , Idioma , História do Século XX , Itália , Biologia/história
18.
Clin Transl Med ; 12(11): e1111, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36394204

RESUMO

BACKGROUND: Telomerase is a ribonucleoprotein complex consisting of a catalytic component telomerase reverse transcriptase (TERT), internal RNA template and other co-factors, and its essential function is to synthesize telomeric DNA, repetitive TTAGGG sequences at the termini of linear chromosomes. Telomerase is silent in normal human follicular thyroid cells, primarily due to the TERT gene being tightly repressed. During the development and progression of thyroid carcinomas (TCs), TERT induction and telomerase activation is in general required to maintain telomere length, thereby conferring TC cells with immortal and aggressive phenotypes. METHODS: The genomic alterations of the TERT loci including TERT promoter's gain-of-function mutations, copy number gain, fusion and rearrangements, have recently been identified in TCs as mechanisms to induce TERT expression and to activate telomerase. Importantly, numerous studies have consistently shown that TERT promoter mutations and TERT expression occur in all TC subtypes, and are robustly associated with TC malignancy, aggressiveness, treatment failure and poor outcomes. Therefore, the assessment of TERT promoter mutations and TERT expression is highly valuable in TC diagnostics, prognosis, treatment decision, and follow-up design. In addition, the TERT promoter is frequently hypermethylated in TC cells and tumors, which is required to activate TERT transcription and telomerase. Dysregulation of other components in the telomerase complex similarly upregulate telomerase. Moreover, shortened telomeres lead to altered gene expression and metabolism, thereby actively promoting TC aggressiveness. Here we summarize recent findings in TCs to provide the landscape of TC-featured telomere/telomerase biology and discuss underlying implications in TC precision medicine. CONCLUSION: Mechanistic insights into telomerase activation and TERT induction in TCs are important both biologically and clinically. The TERT gene aberration and expression-based molecular classification of TCs is proposed, and for such a purpose, the standardization of the assay and evaluation system is required. Moreover, the TERT-based system and 2022 WHO TC classification may be combined to improve TC care.


Assuntos
Telomerase , Neoplasias da Glândula Tireoide , Humanos , Telomerase/genética , Telomerase/metabolismo , Neoplasias da Glândula Tireoide/diagnóstico , Neoplasias da Glândula Tireoide/genética , Telômero/genética , Telômero/metabolismo , Homeostase do Telômero/genética , Biologia
19.
Biol Open ; 11(11)2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36416384

Assuntos
Biologia
20.
Theor Biol Forum ; 115(1-2): 13-28, 2022 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36325929

RESUMO

We may induce from a longue durée examination of Anglo-American History of Biology that the impulse to reject reduc - tionism persists and will continue to percolate cyclically. This impulse I deem "bioexceptionalism": an intuition, stance, attitude, or activating metaphor that the study of living beings requires explanations in addition to exclusively bottom-up causal explanations and the research programs constructed upon that bottom-up philosophical foundation by non-organismal biologists, biochemists, and biophysicists - the explanations, in other words, that Wadding - ton (1977) humorously termed the "Conventional Wisdom of the Dominant Group, or cowdung." Bioexceptionalism might indicate an ontological assertion, like vitalism. Yet most often in the last century, it has been defined by a variety of methodological or even sociological positions. On three occasions in the interval from the late nineteenth century to the present, a small but significant group of practicing biologists and allies in other research disciplines in the UK and US adopted a species of bioexceptionalism, rejecting the dominant explanatory philosophy of reductionistic mechanism. Yet they also rejected the vitalist alternative. We can refer to their subset of bioexceptionalism as a "Third-Way" approach, though participants at the time called it by a variety of names, including "organicism." Today's appeals to a Third-Way are but the latest eruption of this older dissensus and retain at least heuristic value apart from any explanatory success.


Assuntos
Biologia , Vitalismo , Humanos , Biologia/história , Vitalismo/história , Filosofia/história , Sociologia , Metáfora
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