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Cancer remains one of the most challenging diseases to treat. For accurate cancer diagnosis and targeted therapy, it is important to assess the localization of the affected area of cancers. The general approaches for cancer diagnostics include pathological assessments and imaging. However, these methods only generally assess the tumor area. In this study, by taking advantage of the unique microenvironment of cancers, we effectively utilize in situ self-assembled biosynthetic fluorescent gold nanocluster-DNA (GNC-DNA) complexes to facilitate safe and targeted cancer theranostics. In in vitro and in vivo tumor models, our self-assembling biosynthetic approach allowed for precise bioimaging and inhibited cancer growth after one injection of DNA and gold precursors. These results demonstrate that in situ bioresponsive self-assembling GNC-PTEN (phosphatase and tensin homolog) complexes could be an effective noninvasive technique for accurate cancer bioimaging and treatment, thus providing a safe and promising cancer theranostics platform for cancer therapy.
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DNA/química , Ouro/química , Nanopartículas Metálicas/química , Nanopartículas Metálicas/uso terapêutico , PTEN Fosfo-Hidrolase/efeitos dos fármacos , Nanomedicina Teranóstica/métodos , Células A549 , Animais , Linhagem Celular Tumoral , Modelos Animais de Doenças , Células HeLa , Humanos , Camundongos , Neoplasias/tratamento farmacológico , Neoplasias/genética , PTEN Fosfo-Hidrolase/genética , Microambiente TumoralRESUMO
Plants have evolved complex mechanisms to cope with the fluctuating environmental availability of nitrogen. However, potential genes modulating plant responses to nitrate are yet to be characterized. Here, a poplar GATA transcription factor gene PdGNC (GATA nitrate-inducible carbon-metabolism-involved) was found to be strongly induced by low nitrate. Overexpressing PdGNC in poplar clone 717-1B4 (P. tremula × alba) significantly improved nitrate uptake, remobilization, and assimilation with higher nitrogen use efficiency (NUE) and faster growth, particularly under low nitrate conditions. Conversely, CRISPR/Cas9-mediated poplar mutant gnc exhibited decreased nitrate uptake, relocation, and assimilation, combined with lower NUE and slower growth. Assays with yeast one-hybrid, electrophoretic mobility shift, and a dual-luciferase reporter showed that PdGNC directly activated the promoters of nitrogen pathway genes PdNRT2.4b, PdNR, PdNiR, and PdGS2, leading to a significant increase in nitrate utilization in poplar. As expected, the enhanced NUE promoted growth under low nitrate availability. Taken together, our data show that PdGNC plays an important role in the regulation of NUE and growth in poplar by improving nitrate acquisition, remobilization, and assimilation, and provide a promising strategy for molecular breeding to improve productivity under nitrogen limitation in trees.
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Nitrogênio , Populus , Regulação da Expressão Gênica de Plantas , Nitratos/metabolismo , Nitrogênio/metabolismo , Populus/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
BRAHMA (BRM) is the ATPase of the SWItch/Sucrose Non-Fermentable (SWI/SNF) chromatin remodelling complex, which is indispensable for transcriptional inhibition and activation, associated with vegetative and reproductive development in Arabidopsis thaliana. Here, we show that BRM directly binds to the chromatin of SUPPRESSOR OF OVEREXPRESSION OF CONSTANS 1 (SOC1), which integrates multiple flowering signals to regulate floral transition, leading to flowering. In addition, genetic and molecular analysis showed that BRM interacts with GNC (GATA, NITRATE-INDUCIBLE, CARBON METABOLISM INVOLVED), a GATA transcription factor that represses flowering by directly repressing SOC1 expression. Furthermore, BRM is recruited by GNC to directly bind to the chromatin of SOC1. The transcript level of SOC1 is elevated in brm-3, gnc, and brm-3/gnc mutants, which is associated with increased histone H3 lysine 4 tri-methylation (H3K4Me3) but decreased DNA methylation. Taken together, our results indicate that BRM associates with GNC to regulate SOC1 expression and flowering time.
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Adenosina Trifosfatases , Proteínas de Arabidopsis , Arabidopsis , Montagem e Desmontagem da Cromatina , Fatores de Transcrição , Adenosina Trifosfatases/genética , Adenosina Trifosfatases/metabolismo , Arabidopsis/crescimento & desenvolvimento , Arabidopsis/metabolismo , Proteínas de Arabidopsis/genética , Proteínas de Arabidopsis/metabolismo , Fatores de Transcrição GATA/genética , Fatores de Transcrição GATA/metabolismo , Regulação da Expressão Gênica de Plantas , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismoRESUMO
Growing evidence has indicated that microRNAs (miRNAs) are modulators of osteoarthritis (OA) development and progression. In this study, we first evaluated the anti-apoptosis and chondroprotective effects of microRNA-675-3p (miR-675-3p) on interleukin-1ß (IL-1ß)-stimulated human chondrocytes. The overexpression of miR-675-3p inhibited apoptosis and cartilage matrix degradation and promoted cell proliferation in human chondrocytes. Target gene prediction and luciferase reporter assays suggested that G-protein subunit γ 5 (GNG5) may be the target gene of miR-675-3p. The overexpression of miR-675-3p inhibited IL-1ß-stimulated chondrocyte apoptosis, and this effect was reversed by the overexpression of GNG5. Finally, we used bioinformatic tools and biological methods to show that the long noncoding RNA X-inactive specific transcript (lncRNA XIST) could bind to miR-675-3p, which affects the expression of GNG5 mRNA. Our findings may substantiate miR-675-3p as a new treatment for OA.
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Apoptose , Condrócitos/citologia , Subunidades gama da Proteína de Ligação ao GTP/genética , Interleucina-1beta/metabolismo , MicroRNAs/genética , Cartilagem/metabolismo , Cartilagem/patologia , Células Cultivadas , Condrócitos/metabolismo , Condrócitos/patologia , Humanos , Inflamação/genética , Inflamação/metabolismo , Osteoartrite/genética , Osteoartrite/metabolismo , Osteoartrite/patologia , Regulação para CimaRESUMO
Early detection and treatment of cardiovascular disease by identifying markers is important to improve the health of our citizens and simultaneously reduce the cost of health care. Therefore, there is an urgent need for early detection and treatment of asymptomatic cardiovascular disease. Herein, we have developed highly sensitive vertical flow immunokit (VFIK) for the detection of C-reactive protein (CRP), comprising an antibody/citrate conjugated gold nanoparticle in a fixed orientation surface. Our CRP test kit has been optimized with various parameters such as buffer composition, the quantity of captured antibody and sensitivity of the assay. Prominently, our developed CRP test kit is highly sensitive and rapid point of care test (POCT) which is capable to detect CRP with minimal volume (50-60 µl) and time (1-2 min) with diminutive detection up to 10 ng/ml. The reliability of our kit was evaluated and validated with spiked and clinical whole blood samples. The results demonstrated that our developed vertical flow-based point-of-care Immunokit may serve fruitful and semi-quantitative routine diagnostic for the early detection of cardiac disease.
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Proteína C-Reativa/metabolismo , Doenças Cardiovasculares/diagnóstico , Doenças Cardiovasculares/metabolismo , Imunoensaio/instrumentação , Sistemas Automatizados de Assistência Junto ao Leito , Diagnóstico Precoce , Humanos , Fatores de Risco , Sensibilidade e Especificidade , Fatores de TempoRESUMO
BACKGROUND: Noise annoyance is associated with adverse health-related conditions and reduced wellbeing. Thereby, subjective noise annoyance depends on the objective noise exposure and is modified by personal and regional factors. OBJECTIVE: How many participants of the German National Cohort Study (GNC; NAKO Gesundheitsstudie) were annoyed by transportation noise during nighttime and what factors were associated with noise annoyance? MATERIALS AND METHODS: This cross-sectional analysis included 86,080 participants from 18 study centers, examined from 2014 to 2017. We used multinomial logistic regression to investigate associations of personal and regional factors to noise annoyance (slightly/moderately or strongly/extremely annoyed vs. not annoyed) mutually adjusting for all factors in the model. RESULTS: Two thirds of participants were not annoyed by transportation noise during nighttime and one in ten reported strong/extreme annoyance with highest percentages for the study centers Berlin-Mitte and Leipzig. The strongest associations were seen for factors related to the individual housing situation like the bedroom being positioned towards a major road (OR of being slightly/moderately annoyed: 4.26 [95% CI: 4.01;4.52]; OR of being strongly/extremely annoyed: 13.36 [95% CI: 12.47;14.32]) compared to a garden/inner courtyard. Participants aged 40-60 years and those in low- and medium-income groups reported greater noise annoyance compared to younger or older ones and those in the high-income group. CONCLUSION: In this study from Germany, transportation noise annoyance during nighttime varied by personal and regional factors.
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Exposição Ambiental , Ruído dos Transportes , Berlim , Estudos de Coortes , Estudos Transversais , Alemanha , Inquéritos e QuestionáriosRESUMO
BACKGROUND: Caries and periodontitis are highly prevalent worldwide. Because detailed data on these oral diseases were collected within the framework of the German National Cohort (GNC), associations between oral and systemic diseases and conditions can be investigated. OBJECTIVES: The study protocol for the oral examination was designed to ensure a comprehensive collection of dental findings by trained non-dental staff within a limited examination time. At the mid-term of the GNC baseline examination, a first quality evaluation was performed to check the plausibility of results and to propose measures to improve the data quality. MATERIALS AND METHODS: A dental interview, saliva sampling and oral diagnostics were conducted. As part of the level1 examination, the number of teeth and prostheses were recorded. As part of the level2 examination, detailed periodontal, cariological and functional aspects were examined. All examinations were conducted by trained non-dental personnel. Parameters were checked for plausibility and variable distributions were descriptively analysed. RESULTS: Analyses included data of 57,967 interview participants, 56,913 level1 participants and 6295 level2 participants. Percentages of missing values for individual clinical parameters assessed in level 1 and level 2 ranged between 0.02 and 3.9%. Results showed a plausible distribution of the data; rarely, implausible values were observed, e.g. for measurements of horizontal and vertical overbite (overjet and overbite). Intra-class correlation coefficients indicated differences in individual parameters between regional clusters, study centres and across different examiners. CONCLUSIONS: The results confirm the feasibility of the study protocol by non-dental personnel and its successful integration into the GNC's overall assessment program. However, rigorous dental support of the study centres is required for quality management.
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Coleta de Dados/normas , Cárie Dentária , Doenças da Boca , Saúde Bucal , Estudos de Coortes , Cárie Dentária/epidemiologia , Alemanha , Humanos , Garantia da Qualidade dos Cuidados de Saúde , Controle de QualidadeRESUMO
BACKGROUND: Infectious diseases continue to play an important role for disease perception, health-economic considerations and public health in Germany. In recent years, infectious diseases have been linked to the development of non-communicable diseases. Analyses of the German National Cohort (GNC) may provide deeper insights into this issue and pave the way for new targeted approaches in disease prevention. OBJECTIVES: The aim was to describe the tools used to assess infectious diseases and to present initial data on infectious disease frequencies, as well as to relate the GNC assessment tools to data collection methods in other studies in Germany. METHODS: As part of the baseline examination, questions regarding infectious diseases were administered using both an interview and a self-administered touchscreen questionnaire. Data from the initial 101,787 GNC participants were analysed. RESULTS: In the interview, 0.2% (HIV/AIDS) to 8.6% (shingles) of respondents reported ever having a medical diagnosis of shingles, postherpetic neuralgia (in cases where shingles was reported), hepatitis B/C, HIV/AIDS, tuberculosis or sepsis if treated in hospital. In the questionnaire, 12% (cystitis) to 81% (upper respiratory tract infections) of respondents reported having experienced at least one occurrence of upper or lower respiratory tract infections, gastrointestinal infections, cystitis or fever within the past 12 months. OUTLOOK: The cross-sectional analyses of data and tools presented here - for example on determinants of susceptibility to self-reported infections - can be anticipated from the year 2021 onward. Beyond that, more extensive research into infectious disease epidemiology will follow, particularly once analyses of GNC biological materials have been performed.
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Doenças Transmissíveis/epidemiologia , Estudos de Coortes , Estudos Transversais , Alemanha/epidemiologia , Humanos , Autorrelato , Inquéritos e QuestionáriosRESUMO
The riddle of the origin of life is unsolved as yet. One of the best ways to solve the riddle would be to find a vestige of the first life from databases of DNA and/or protein of modern organisms. It would be, especially, important to know the origin of tRNA, because it mediates between genetic information and the amino acid sequence of a protein. Here I attempt to find a vestige of the origin and evolution of tRNA from base sequences of Pseudomonas aeruginosa tRNA gene. It was first perceived that 5' anticodon (AntiC) stem sequences of P. aeruginosa tRNA for translation of G-start codon (GNN) are intimately and mutually related. Then, mutual relations among all of the forty-two 5' AntiC stem sequences of P. aeruginosa tRNA were examined. These relationships imply that P. aeruginosa tRNA originated from four anticodon stem-loops (AntiC-SL) translating GNC codons to the corresponding four amino acids, Gly, Ala, Asp and Val (where N is G, C, A, or T). In contrast to the case of AntiC-stem sequence, a mutual relation map could not be drawn with D-, T- and acceptor-stem sequences of P. aeruginosa tRNA. Thus I conclude that the four AntiC-SLs were the first primeval tRNAs.
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Anticódon/análise , Evolução Molecular , Pseudomonas aeruginosa/genética , RNA Bacteriano/análise , RNA de Transferência/análiseRESUMO
Correspondence relations between codons and amino acids are determined by genetic code. Therefore, genetic code holds a key of the life system composed of genes and protein. According to the GNC-SNS primitive genetic code hypothesis, which I have proposed, it is assumed that the genetic code originated from GNC code. In this article, first, it is discussed from a standpoint of primeval protein synthesis, why four [GADV]-amino acids were selected and used in the first GNC code. Next, it is explained from another standpoint of the most primitive anticodon-stem loop tRNAs (AntiC-SL tRNAs), how four GNCs were selected for the first codons. Furthermore, in the last section of this article, I will explain my idea of how the correspondence relations between four [GADV]-amino acids and four GNC codons were established. Namely, the origin and evolution of the genetic code was discussed comprehensively from several aspects of [GADV]-proteins, [GADV]-amino acids, GNC codons, and anticodon stem-loop tRNAs (AntiC-SL tRNAs), which relate each other to the origin of the genetic code, as integrating GNC code frozen-accident theory, coevolution theory, and adaptive theory on the origin of the genetic code.
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Aminoácidos , Anticódon , Aminoácidos/genética , Evolução Molecular , Código Genético , Códon , RNA de Transferência/genética , Proteínas/genéticaRESUMO
PURPOSE: Creating inclusive LGBTQ+ environments is important in the provision of inclusive care. This cross sectional study assessed whether patient intake forms in pediatric surgery departments were LGBTQ+ inclusive (L-I). METHODS: North American pediatric surgery departments affiliated with pediatric surgery fellowships or general surgery residencies were contacted to retrieve patient intake forms. Forms were assessed for LGBTQ+ inclusivity using a novel L-I scoring system consisting of 6 criteria: preferred name, pronouns, preferred language, gender identity, sex assigned at birth, and l-I guardianship. Institutions without intake forms were invited to comment on their use of l-I intake questions. RESULTS: 59/125 programs responded to our query, 10 of which provided intake forms. Median l-I score was 2/6 points (range 1-4). l-I guardianship was the most common question asked. No intake form asked for pronouns. Of the 49 institutions without forms, 30.5% reported asking l-I questions during initial visits. Narratives from these institutions varied widely. Some institutions supported routine l-I questions while others stated l-I questions were unnecessary, irrelevant, and/or offensive. CONCLUSIONS: Few North American pediatric surgery departments consistently ask l-I questions during the intake process. Comments questioning the appropriateness and necessity of l-I questions highlight the need for LGBTQ+ education. LEVEL OF EVIDENCE: Level III. TYPE OF STUDY: Cross sectional study.
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Minorias Sexuais e de Gênero , Instituições de Assistência Ambulatorial , Criança , Estudos Transversais , Feminino , Identidade de Gênero , Humanos , Recém-Nascido , Masculino , Comportamento SexualRESUMO
BACKGROUND: Young cisgender men who have sex with men (YMSM), young transgender women (YTW), and gender nonconforming (GNC) youth of color face substantial economic and health disparities. In particular, HIV risk and infection among these groups remains a significant public health issue. In 2017, 17% of all new HIV diagnoses were attributed to male-to-male sexual contact among adolescents and young adults aged 13 to 24 years. However, such disparities cannot be attributed to individual-level factors alone but rather are situated within larger social and structural contexts that marginalize and predispose YMSM, YTW, and GNC youth of color to increased HIV exposure. Addressing social and structural risk factors requires intervention on distal drivers of HIV risk, including employment and economic stability. The Work2Prevent (W2P) study aims to target economic stability through job readiness and employment as a structural-level intervention for preventing adolescent and young adult HIV among black and Latinx YMSM, YTW, and GNC youth. This study seeks to assess intervention feasibility and acceptability in the target populations and determine preliminary efficacy of the intervention to increase employment and reduce sexual risk behaviors. OBJECTIVE: The goal of the research is to pilot-test a tailored, theoretically informed employment intervention program among YMSM, YTW, and GNC youth of color. This intervention was adapted from Increased Individual Income and Independence, an existing evidence-based employment program for HIV-positive adults during phase 1 of the W2P study. METHODS: The employment intervention will be pilot-tested among vulnerable YMSM, YTW, and GNC youth of color in a single-arm pre-post trial to assess feasibility, acceptability, and preliminary estimates of efficacy. RESULTS: Research activities began in March 2018 and were completed in November 2019. Overall, 5 participants were enrolled in the pretest and 51 participants were enrolled in the pilot. CONCLUSIONS: Interventions that address the social and structural drivers of HIV exposure and infection are sorely needed in order to successfully bend the curve in the adolescent and young adult HIV epidemic. Employment as prevention has the potential to be a scalable intervention that can be deployed among this group. TRIAL REGISTRATION: ClinicalTrials.gov NCT03313310; https://clinicaltrials.gov/ct2/show/NCT03313310. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/16401.
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BACKGROUND: HIV continues to have a disparate impact on young cisgender men who have sex with men (YMSM), young trans women (YTW), and gender-nonconforming (GNC) youth who are assigned male at birth. Outcomes are generally worse among youth of color. Experiences of discrimination and marginalization often limit educational attainment and may even more directly limit access to gainful employment. Though seemingly distal, these experiences influence young people's proximity to HIV risk by limiting their access to health care and potentially moving them toward sex work as a means of income as well as increased substance use. Work2Prevent (W2P) aims to achieve economic stability through employment as a structural-level intervention for preventing adolescent and young adult HIV infection. The study will pilot-test an effective, theoretically driven employment program (increased individual income and independence [iFOUR]), for HIV-positive adults, and adapt it to the needs of black and Latinx YMSM, YTW, and GNC youth aged 16 to 24 years who are vulnerable to HIV exposure. OBJECTIVE: This paper aimed to describe the protocol for the exploratory phase of W2P. The purpose of this phase was to determine the essential components needed for a structural-level employment intervention aimed at increasing job-seeking self-efficacy and career readiness among black and Latinx YMSM, YTW, and GNC youth aged 16 to 24 years. METHODS: The exploratory phase of the W2P study consisted of in-depth interviews and focus groups with members of the target community as well as brief interviews with lesbian, gay, bisexual, transgender, and queer (LGBTQ)-inclusive employers. The study team will conduct in-depth interviews with up to 12 YMSM and 12 YTW and GNC youth, up to 10 focus groups with a maximum of 40 YMSM and 40 YTW and GNC youth, and up to 40 brief interviews with LGBTQ-inclusive employers. Participants will be recruited through a community-based recruiter, passive recruitment in community spaces and on social media, and active recruitment by research staff in community spaces serving LGBTQ youth. RESULTS: In-depth interviews were conducted with 21 participants, and 7 focus groups were conducted with 46 participants in total. In addition, 19 brief interviews with LGBTQ-inclusive employers were conducted. The analysis of the data is underway. CONCLUSIONS: Preliminary findings from the formative phase of the study will be used to inform the tailoring and refinement of the iFOUR adult-based intervention into the youth-focused W2P intervention curriculum. Perspectives from YMSM, YTW, GNC youth, and LGBTQ-inclusive employers offer a multidimensional view of the barriers and facilitators to adolescent and young adult LGBTQ employment. This information is critical to the development of a culturally appropriate and relevant youth-focused intervention. TRIAL REGISTRATION: ClinicalTrials.gov NCT03313310; https://clinicaltrials.gov/ct2/show/NCT03313310. INTERNATIONAL REGISTERED REPORT IDENTIFIER (IRRID): DERR1-10.2196/16384.
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BACKGROUND: C3 glomerulopathy (C3G) is related to dysfunction of alternative complement pathway (ACP) because of its hyperactivation. Triggering factors and genetic profile are likely to be different in developing countries as compared to the Western world. Data regarding C3G from South Asian is scanty. STUDY DESIGN: In the present study, 115 patients of C3G from 2012 to 2017 were analyzed. Clinical details were reviewed; serological levels of C3, C4, complement factor H or B and autoantibody testing was done by nephelometry/ELISA. Limited genetics workup for CFH and CFHR5 genes was done. RESULTS: The prevalence of C3G was 1.52%. There was no difference in demographic and histopathologic profiles of C3G patients. Majority of patients had low functional assay and C3 levels. C3 nephritic factor was present in 47.5% of DDD and 38.6% of C3GN. Autoantibodies to CFH were present more often in the patients of C3GN (29.5%) than DDD (12.5%). Autoantibodies to CFB were equally common in both groups. Past history of infections was present in one-third patients and monoclonal paraproteins were present only in two patients. No pathogenic variants were noted in CFH/CFHR5 gene. On follow-up (3.2 + 1.6 years), complete and partial remission was achieved in one-fourth patients and 26% had resistance disease. About 40% progressed to ESRD and 18 underwent renal transplantation of which nine had a post-transplant recurrence. CONCLUSIONS: Indian cohort had some differences in the immunological and genetic profile when compared to the Western literature; most significant was the absence of monoclonal immunoglobulins as a trigger for C3G.
Assuntos
Glomerulonefrite Membranoproliferativa , Nefropatias , Transplante de Rim , Fator Nefrítico do Complemento 3/genética , Via Alternativa do Complemento/genética , Glomerulonefrite Membranoproliferativa/diagnóstico , Glomerulonefrite Membranoproliferativa/epidemiologia , Glomerulonefrite Membranoproliferativa/genética , HumanosRESUMO
BACKGROUND: In this article, incidental findings (IF) refer to unforeseen findings made possible through biobanking research and advances in medical diagnostic technologies that raise issues regarding the obligation and/or responsibility of biobank-users and biobanks to return clinically significant information to participants. The World Medical Association (WMA) Declaration of Taipei (2016) highlights the possibility of encountering IF and requires that research on biospecimens address biobank feedback policies in their informed consent process, leaving open the possibility that the policy may be "no return". As clinicians and researchers begin to use these "resources", the possibility of finding clinically significant IF is becoming a reality. DISCUSSION: In line with the WMA's Declaration of Taipei, a pragmatic approach is needed to deal with the issue of returning IF in biobank governance. Indeed, the impacts and concerns associated with the return of IF differ across different stakeholder groups and jurisdictions. Therefore, the framework governing IF return needs to be custom-built, taking into account the nature of each research project and the unique features of biobanks. To this end, in addition to facilitating biobank transparency, establishing an endurable and horizontal connection among biobanks and clinical institutions under a public health system will improve efficiency and effectiveness. Hence, subject to contemporary Taiwanese ethical and/or legal regulations, this article argues for the establishment of an updated framework for imaging-related and genetic-related IF return within the Taiwan Biobank (TWB), mainly based on a limited obligation to disclose life-threatening information revealed by imaging, but not genetic, information. SUMMARY: After discussing some of the ethical, legal and social issues encountered by the TWB and accounting for the experiences of other international biobanks, we propose a systematic framework for returning IF, mainly on a "limited obligation" basis, which offers better and more comprehensive protection for biobank-participants' rights and health.
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GATA transcription factors are evolutionarily conserved transcriptional regulators that recognize promoter elements with a G-A-T-A core sequence. In comparison to animal genomes, the GATA transcription factor family in plants is comparatively large with approximately 30 members. Here, we review the current knowledge on B-GATAs, one of four GATA factor subfamilies from Arabidopsis thaliana. We show that B-GATAs can be subdivided based on structural features and their biological function into family members with a C-terminal LLM- (leucine-leucine-methionine) domain or an N-terminal HAN- (HANABA TARANU) domain. The paralogous GNC (GATA, NITRATE-INDUCIBLE, CARBON-METABOLISM INVOLVED) and CGA1/GNL (CYTOKININ-INDUCED GATA1/GNC-LIKE) are introduced as LLM-domain containing B-GATAs from Arabidopsis that control germination, greening, senescence, and flowering time downstream from several growth regulatory signals. Arabidopsis HAN and its monocot-specific paralogs from rice (NECK LEAF1), maize (TASSEL SHEATH1), and barley (THIRD OUTER GLUME) are HAN-domain-containing B-GATAs with a predominant role in embryo development and floral development. We also review GATA23, a regulator of lateral root initiation from Arabidopsis that is closely related to GNC and GNL but has a degenerate LLM-domain that is seemingly specific for the Brassicaceae family. The Brassicaceae-specific GATA23 and the monocot-specific HAN-domain GATAs provide evidence that neofunctionalization of B-GATAs was used during plant evolution to expand the functional repertoire of these transcription factors.
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Eukaryotic GCN2 (general control nonderepressible 2) is a serine/threonine protein kinase that plays an essential role in modulating amino acid metabolism in response to nutrient deprivation. A wide spectrum of GCN2 functions in yeast and mammals has been characterized that spans from responses to amino acid deficiency, development, differentiation and proper functions of mammalian organs to organism's life span, tumor cell survival and immune responses. Here we demonstrate that Arabidopsis thaliana GCN2 (AtGCN2) plays crucial roles in plant growth and development. We present evidence that AtGCN2 negatively regulates seed germination under diverse environmental conditions. Our genetic data supported the notion that AtGCN2 is required for leaf morphology and normal cellular physiology by controlling chlorophyll contents. Our gene expression analyses revealed that AtGCN2 negatively regulates several transcription factor genes that play important roles in plant gibberellic acid-related crosstalk. We concluded that AtGCN2 plays pivotal roles in various cellular processes essential for normal growth and development, hence expanding the functions of this general regulator beyond being merely a stress player.