Transcriptome analysis reveals rice MADS13 as an important repressor of the carpel development pathway in ovules

Abstract In angiosperms, floral homeotic genes encoding MADS-domain transcription factors regulate the development of floral organs. Specifically, members of the SEPALLATA (SEP) and AGAMOUS (AG) subfamilies form higher-order protein complexes to control floral meristem determinacy and to specify the identity of female reproductive organs. In rice, the AG subfamily gene OsMADS13 is intimately involved in the determination of ovule identity, since knock-out mutant plants develop carpel-like structures in place of ovules, resulting in female sterility. Little is known about the regulatory pathways at the base of rice gynoecium development. To investigate molecular mechanisms acting downstream of OsMADS13, we obtained transcriptomes of immature inflorescences from wild-type and Osmads13 mutant plants. Among a total of 476 differentially expressed genes (DEGs), a substantial overlap with DEGs from the SEP-family Osmads1 mutant was found, suggesting that OsMADS1 and OsMADS13 may act on a common set of target genes. Expression studies and preliminary analyses of two up-regulated genes encoding Zinc-finger transcription factors indicated that our dataset represents a valuable resource for the identification of both OsMADS13 target genes and novel players in rice ovule development. Taken together, our study suggests that OsMADS13 is an important repressor of the carpel pathway during ovule development.

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Rare genetic variants in GATA transcription factors in patients with hypertrophic cardiomyopathy

Journal of Investigative Medicine ◽

10.1136/jim-2016-000364 ◽

2017 ◽

Vol 65 (5) ◽

pp. 926-934 ◽

Cited By ~ 3

Author(s):

Cristina Alonso-Montes ◽

Julián Rodríguez-Reguero ◽

María Martín ◽

Juan Gómez ◽

Eliecer Coto ◽

...

Keyword(s):

Transcription Factors ◽

Hypertrophic Cardiomyopathy ◽

Molecular Mechanisms ◽

Target Genes ◽

Rare Variants ◽

Posterior Wall ◽

Potential Candidate ◽

Sarcomeric Proteins ◽

Gata Transcription Factors ◽

Genes Encoding

Hypertrophic cardiomyopathy (HCM) is a very heterogeneous disease. Although primarily caused by mutations in genes encoding sarcomeric proteins, other genes might explain that heterogeneity. Potential candidate genes are GATA transcription factors that regulate the expression of proteins associated with HCM. Exons ofGATA2,GATA4, andGATA6genes were sequenced in 212 patients with unrelated HCM previously analyzed for genes encoding the most frequently mutated sarcomeric proteins. Functional effects of variants were predicted by in silico analyses. 3 potentially pathogenic variants were identified: c.-77G>A inGATA2, p.Ala343Thr (rs370588269) inGATA4, and p.Pro555Ala (rs146243018) inGATA6. Multivariate analyses showed that angina was more frequent in patients carrying sarcomeric and GATA rare variants (55% vs 23.2% in non-carriers of GATA rare variants, OR (95% CI) 7.12 (1.23 to 41.27), p=0.029). Among patients without a known causal mutation, GATA rare variants were associated with a greater maximum posterior wall thickness (16.4±4.4 vs 14.0±3.1 mm in non-carriers, p=0.021). Thus, variants having a putative effect on GATA genes would alter the expression of their target genes and could modify the hypertrophic response. Therefore, although relatively infrequent in patients with HCM, they may represent a novel insight into the molecular mechanisms related to the pathogenesis of HCM.

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Role of Satb1 and Satb2 Transcription Factors in the Glutamate Receptors Expression and Ca2+ Signaling in the Cortical Neurons In Vitro

International Journal of Molecular Sciences ◽

10.3390/ijms22115968 ◽

2021 ◽

Vol 22 (11) ◽

pp. 5968

Author(s):

Egor A. Turovsky ◽

Maria V. Turovskaya ◽

Evgeniya I. Fedotova ◽

Alexey A. Babaev ◽

Viktor S. Tarabykin ◽

...

Keyword(s):

Transcription Factors ◽

Nmda Receptor ◽

Cortical Neurons ◽

Target Genes ◽

Cortical Cell ◽

Inhibitory System ◽

Selective Agonist ◽

Genes Encoding ◽

Deficient Mice

Transcription factors Satb1 and Satb2 are involved in the processes of cortex development and maturation of neurons. Alterations in the expression of their target genes can lead to neurodegenerative processes. Molecular and cellular mechanisms of regulation of neurotransmission by these transcription factors remain poorly understood. In this study, we have shown that transcription factors Satb1 and Satb2 participate in the regulation of genes encoding the NMDA-, AMPA-, and KA- receptor subunits and the inhibitory GABA(A) receptor. Deletion of gene for either Satb1 or Satb2 homologous factors induces the expression of genes encoding the NMDA receptor subunits, thereby leading to higher amplitudes of Ca2+-signals in neurons derived from the Satb1-deficient (Satb1fl/+ * NexCre/+) and Satb1-null mice (Satb1fl/fl * NexCre/+) in response to the selective agonist reducing the EC50 for the NMDA receptor. Simultaneously, there is an increase in the expression of the Gria2 gene, encoding the AMPA receptor subunit, thus decreasing the Ca2+-signals of neurons in response to the treatment with a selective agonist (5-Fluorowillardiine (FW)). The Satb1 deletion increases the sensitivity of the KA receptor to the agonist (domoic acid), in the cortical neurons of the Satb1-deficient mice but decreases it in the Satb1-null mice. At the same time, the Satb2 deletion decreases Ca2+-signals and the sensitivity of the KA receptor to the agonist in neurons from the Satb1-null and the Satb1-deficient mice. The Satb1 deletion affects the development of the inhibitory system of neurotransmission resulting in the suppression of the neuron maturation process and switching the GABAergic responses from excitatory to inhibitory, while the Satb2 deletion has a similar effect only in the Satb1-null mice. We show that the Satb1 and Satb2 transcription factors are involved in the regulation of the transmission of excitatory signals and inhibition of the neuronal network in the cortical cell culture.

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High Energy Intake Induced Overexpression of Transcription Factors and Its Regulatory Genes Involved in Acceleration of Hepatic Lipogenesis: A Rat Model for Type 2 Diabetes

Biomedicines ◽

10.3390/biomedicines7040076 ◽

2019 ◽

Vol 7 (4) ◽

pp. 76 ◽

Cited By ~ 3

Author(s):

Suresh P. Khadke ◽

Aniket A. Kuvalekar ◽

Abhay M. Harsulkar ◽

Nitin Mantri

Keyword(s):

Type 2 Diabetes ◽

Transcription Factors ◽

Glucose Tolerance ◽

Molecular Mechanisms ◽

Target Genes ◽

High Energy ◽

Tolerance Test ◽

Diabetic Control ◽

Ppar Γ

Type 2 diabetes mellitus (T2DM) is a metabolic disorder characterized by impaired insulin action and its secretion. The objectives of the present study were to establish an economical and efficient animal model, mimicking pathophysiology of human T2DM to understand probable molecular mechanisms in context with lipid metabolism. In the present study, male Wistar rats were randomly divided into three groups. Animals were fed with high fat diet (HFD) except healthy control (HC) for 12 weeks. After eight weeks, intra peritoneal glucose tolerance test was performed. After confirmation of glucose intolerance, diabetic control (DC) group was injected with streptozotocin (STZ) (35 mg/kg b.w., i.p.). HFD fed rats showed increase (p ≤ 0.001) in glucose tolerance and HOMA-IR as compared to HC. Diabetes rats showed abnormal (p ≤ 0.001) lipid profile as compared to HC. The hepatocyte expression of transcription factors SREBP-1c and NFκβ, and their target genes were found to be upregulated, while PPAR-γ, CPT1A and FABP expressions were downregulated as compared to the HC. A number of animal models have been raised for studying T2DM, but the study has been restricted to only the biochemical level. The model is validated at biochemical, molecular and histopathological levels, which can be used for screening new therapeutics for the effective management of T2DM.

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Identification of the Q Gene Playing a Role in Spike Morphology Variation in Wheat Mutants and Its Regulatory Network

Frontiers in Plant Science ◽

10.3389/fpls.2021.807731 ◽

2022 ◽

Vol 12 ◽

Author(s):

Jiazi Zhang ◽

Hongchun Xiong ◽

Huijun Guo ◽

Yuting Li ◽

Xiaomei Xie ◽

...

Keyword(s):

Regulatory Network ◽

Molecular Mechanisms ◽

Target Genes ◽

Expression Patterns ◽

Spike Morphology ◽

Regulatory Pathways ◽

Dynamic Expression ◽

Spike Development ◽

Family Gene ◽

Q Gene

The wheat AP2 family gene Q controls domestication traits, including spike morphology and threshability, which are critical for the widespread cultivation and yield improvement of wheat. Although many studies have investigated the molecular mechanisms of the Q gene, its direct target genes, especially those controlling spike morphology, are not clear, and its regulatory pathways are not well established. In this study, we conducted gene mapping of a wheat speltoid spike mutant and found that a new allele of the Q gene with protein truncation played a role in spike morphology variation in the mutant. Dynamic expression levels of the Q gene throughout the spike development process suggested that the transcript abundances of the mutant were decreased at the W6 and W7 scales compared to those of the WT. We identified several mutation sites on the Q gene and showed that mutations in different domains resulted in distinct phenotypes. In addition, we found that the Q gene produced three transcripts via alternative splicing and that they exhibited differential expression patterns in nodes, internodes, flag leaves, and spikes. Finally, we identified several target genes directly downstream of Q, including TaGRF1-2D and TaMGD-6B, and proposed a possible regulatory network. This study uncovered the target genes of Q, and the results can help to clarify the mechanism of wheat spike morphology and thereby improve wheat grain yield.

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Developmental Genes and Malformations in the Hypothalamus

Frontiers in Neuroanatomy ◽

10.3389/fnana.2020.607111 ◽

2020 ◽

Vol 14 ◽

Author(s):

Carmen Diaz ◽

Luis Puelles

Keyword(s):

Transcription Factors ◽

Energy Metabolism ◽

Molecular Mechanisms ◽

Review Article ◽

Pituitary Development ◽

Forebrain Development ◽

Physiological Processes ◽

Brain Malformations ◽

Clinical Complexity ◽

Genes Encoding

The hypothalamus is a heterogeneous rostral forebrain region that regulates physiological processes essential for survival, energy metabolism, and reproduction, mainly mediated by the pituitary gland. In the updated prosomeric model, the hypothalamus represents the rostralmost forebrain, composed of two segmental regions (terminal and peduncular hypothalamus), which extend respectively into the non-evaginated preoptic telencephalon and the evaginated pallio-subpallial telencephalon. Complex genetic cascades of transcription factors and signaling molecules rule their development. Alterations of some of these molecular mechanisms acting during forebrain development are associated with more or less severe hypothalamic and pituitary dysfunctions, which may be associated with brain malformations such as holoprosencephaly or septo-optic dysplasia. Studies on transgenic mice with mutated genes encoding critical transcription factors implicated in hypothalamic-pituitary development are contributing to understanding the high clinical complexity of these pathologies. In this review article, we will analyze first the complex molecular genoarchitecture of the hypothalamus resulting from the activity of previous morphogenetic signaling centers and secondly some malformations related to alterations in genes implicated in the development of the hypothalamus.

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Regulation of cell survival and proliferation by the FOXO (Forkhead box, class O) subfamily of Forkhead transcription factors

Biochemical Society Transactions ◽

10.1042/bst0310292 ◽

2003 ◽

Vol 31 (1) ◽

pp. 292-297 ◽

Cited By ~ 176

Author(s):

K.U. Birkenkamp ◽

P.J. Coffer

Keyword(s):

Transcription Factors ◽

Cell Survival ◽

Cell Fate ◽

Nuclear Export ◽

Molecular Mechanisms ◽

Target Genes ◽

Acute Lymphocytic Leukaemia ◽

Cell Fate Decisions ◽

Forkhead Transcription Factors ◽

Forkhead Box

Recently, the FOXO (Forkhead box, class O) subfamily of Forkhead transcription factors has been identified as direct targets of phosphoinositide 3-kinase-mediated signal transduction. The AFX (acute-lymphocytic-leukaemia-1 fused gene from chromosome X), FKHR (Forkhead in rhabdomyosarcoma) and FKHR-L1 (FKHR-like 1) transcription factors are directly phosphorylated by protein kinase B, resulting in nuclear export and inhibition of transcription. This signalling pathway was first identified in the nematode worm Caenorhabditis elegans, where it has a role in regulation of the life span of the organism. Studies have shown that this evolutionarily conserved signalling module has a role in regulation of both cell-cycle progression and cell survival in higher eukaryotes. These effects are co-ordinated by FOXO-mediated induction of a variety of specific target genes that are only now beginning to be identified. Interestingly, FOXO transcription factors appear to be able to regulate transcription through both DNA-binding-dependent and -independent mechanisms. Our understanding of the regulation of FOXO activity, and defining specific transcriptional targets, may provide clues to the molecular mechanisms controlling cell fate decisions to divide, differentiate or die.

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3,5-T2 alters murine genes relevant for xenobiotic, steroid, and thyroid hormone metabolism

Journal of Molecular Endocrinology ◽

10.1530/jme-15-0159 ◽

2016 ◽

Vol 56 (4) ◽

pp. 311-323 ◽

Cited By ~ 19

Author(s):

Julika Lietzow ◽

Janine Golchert ◽

Georg Homuth ◽

Uwe Völker ◽

Wenke Jonas ◽

...

Keyword(s):

Thyroid Hormone ◽

Molecular Mechanisms ◽

Target Genes ◽

Phase Iii ◽

Whole Body ◽

High Dose ◽

Thyroid Hormone Metabolism ◽

Expression Of Genes ◽

Genes Encoding ◽

Novel Target

The endogenous thyroid hormone (TH) metabolite 3,5-diiodo-l-thyronine (3,5-T2) acts as a metabolically active substance affecting whole-body energy metabolism and hepatic lipid handling in a desirable manner. Considering possible adverse effects regarding thyromimetic action of 3,5-T2 treatment in rodents, the current literature remains largely controversial. To obtain further insights into molecular mechanisms and to identify novel target genes of 3,5-T2 in liver, we performed a microarray-based liver tissue transcriptome analysis of male lean and diet-induced obese euthyroid mice treated for 4 weeks with a dose of 2.5 µg/g bw 3,5-T2. Our results revealed that 3,5-T2 modulates the expression of genes encoding Phase I and Phase II enzymes as well as Phase III transporters, which play central roles in metabolism and detoxification of xenobiotics. Additionally, 3,5-T2 changes the expression of TH responsive genes, suggesting a thyromimetic action of 3,5-T2 in mouse liver. Interestingly, 3,5-T2 in obese but not in lean mice influences the expression of genes relevant for cholesterol and steroid biosynthesis, suggesting a novel role of 3,5-T2 in steroid metabolism of obese mice. We concluded that treatment with 3,5-T2 in lean and diet-induced obese male mice alters the expression of genes encoding hepatic xenobiotic-metabolizing enzymes that play a substantial role in catabolism and inactivation of xenobiotics and TH and are also involved in hepatic steroid and lipid metabolism. The administration of this high dose of 3,5-T2 might exert adverse hepatic effects. Accordingly, the conceivable use of 3,5-T2 as pharmacological hypolipidemic agent should be considered with caution.

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Small-Molecule Hormones: Molecular Mechanisms of Action

International Journal of Endocrinology ◽

10.1155/2013/601246 ◽

2013 ◽

Vol 2013 ◽

pp. 1-21 ◽

Cited By ~ 10

Author(s):

Monika Puzianowska-Kuznicka ◽

Eliza Pawlik-Pachucka ◽

Magdalena Owczarz ◽

Monika Budzińska ◽

Jacek Polosak

Keyword(s):

Transcription Factors ◽

Small Molecule ◽

Molecular Mechanisms ◽

Hormone Receptors ◽

Target Genes ◽

Direct Interaction ◽

Nuclear Hormone Receptors ◽

Membrane Phospholipids ◽

Basal Transcription Factors ◽

Hormonal Stimulus

Small-molecule hormones play crucial roles in the development and in the maintenance of an adult mammalian organism. On the molecular level, they regulate a plethora of biological pathways. Part of their actions depends on their transcription-regulating properties, exerted by highly specific nuclear receptors which are hormone-dependent transcription factors. Nuclear hormone receptors interact with coactivators, corepressors, basal transcription factors, and other transcription factors in order to modulate the activity of target genes in a manner that is dependent on tissue, age and developmental and pathophysiological states. The biological effect of this mechanism becomes apparent not earlier than 30–60 minutes after hormonal stimulus. In addition, small-molecule hormones modify the function of the cell by a number of nongenomic mechanisms, involving interaction with proteins localized in the plasma membrane, in the cytoplasm, as well as with proteins localized in other cellular membranes and in nonnuclear cellular compartments. The identity of such proteins is still under investigation; however, it seems that extranuclear fractions of nuclear hormone receptors commonly serve this function. A direct interaction of small-molecule hormones with membrane phospholipids and with mRNA is also postulated. In these mechanisms, the reaction to hormonal stimulus appears within seconds or minutes.

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An evolutionarily conserved leucine zipper-like motif accounts for strong tetramerization capabilities of SEPALLATA-like MADS-domain transcription factors controlling flower development

10.1101/125294 ◽

2017 ◽

Author(s):

Florian Rümpler ◽

Günter Theißen ◽

Rainer Melzer

Keyword(s):

Transcription Factors ◽

Amino Acid ◽

Flower Development ◽

Leucine Zipper ◽

Molecular Mechanisms ◽

Target Genes ◽

Specific Interaction ◽

Angiosperm Evolution ◽

Protein Protein Interaction ◽

Organ Specific

ABSTRACTThe development of angiosperm flowers is regulated by homeotic MIKC-type MADS-domain transcription factors that activate or repress target genes via the formation of DNA-bound, organ specific tetrameric complexes. The protein-protein interaction (PPI) capabilities differ considerably between different MIKC-type proteins. The floral homeotic protein SEPALLATA3 (SEP3) acts as a hub that incorporates numerous other MADS-domain proteins into tetrameric complexes that would otherwise not form. However, the molecular mechanisms that underlie these promiscuous interactions remain largely unknown. In this study we created a collection of amino acid substitution mutants of SEP3 to quantify the contribution of individual residues on protein tetramerization during DNA-binding, employing methods of molecular biophysics. We show that leucine residues at certain key positions form a leucine zipper structure that is essential for tetramerization of SEP3, whereas the introduction of physicochemically very similar residues at respective sites impedes the formation of DNA-bound tetramers. Comprehensive molecular evolutionary analyses of MADS-domain proteins from a diverse set of flowering plants revealed exceedingly high conservation of the identified leucine residues within SEP3-subfamily proteins throughout angiosperm evolution. In contrast, MADS-domain proteins that are unable to tetramerize among themselves exhibit preferences for other amino acids at homologous sites. Our findings indicate that the subfamily-specific conservation of amino acid residues at just a few key positions account for subfamily-specific interaction capabilities of MADS-domain transcription factors and shaped the present-day structure of the PPI network controlling flower development.

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Metabolic enzymes regulated by the Myc oncogene are possible targets for chemotherapy or chemoprevention

Biochemical Society Transactions ◽

10.1042/bst0350305 ◽

2007 ◽

Vol 35 (2) ◽

pp. 305-310 ◽

Cited By ~ 13

Author(s):

S. Rimpi ◽

J.A. Nilsson

Keyword(s):

Cell Cycle ◽

Transcription Factors ◽

Recent Work ◽

Target Genes ◽

Biological Effects ◽

Metabolic Enzymes ◽

Myc Oncogene ◽

E Box ◽

Genes Encoding ◽

Cell Cycle Machinery

The Myc oncogenes are dysregulated in 70% of human cancers. They encode transcription factors that bind to E-box sequences in DNA, driving the expression of a vast amount of target genes. The biological outcome is enhanced proliferation (which is counteracted by apoptosis), angiogenesis and cancer. Based on the biological effects of Myc overexpression it was originally assumed that the important Myc target genes are those encoding components of the cell cycle machinery. Recent work has challenged this notion and indicates that Myc target genes encoding metabolic enzymes deserve attention, as they may be critical arbiters of Myc in cancer. Thus targeting metabolic enzymes encoded by Myc-target genes may provide a new means to treat cancer that have arisen in response to deregulated Myc oncogenes.

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