scholarly journals Control of neurogenic competence in mammalian hypothalamic tanycytes

2020 ◽  
Author(s):  
Sooyeon Yoo ◽  
Juhyun Kim ◽  
Pin Lyu ◽  
Thanh V. Hoang ◽  
Alex Ma ◽  
...  
Keyword(s):  
Transcription Factors ◽  
Molecular Mechanisms ◽  
Neural Circuitry ◽  
Radial Glial Cells ◽  
Neuronal Progenitors ◽  
Physiological Processes ◽  
Internal States ◽  
Radial Glial ◽  
Synaptic Circuitry ◽  
Deficient Mice

AbstractHypothalamic tanycytes, radial glial cells that share many features with neuronal progenitors, generate small numbers of neurons in the postnatal hypothalamus, but the identity of these neurons and the molecular mechanisms that control tanycyte-derived neurogenesis are unknown. In this study, we demonstrate that tanycyte-specific disruption of the NFI family of transcription factors (Nfia/b/x) robustly stimulates tanycyte proliferation and tanycyte-derived neurogenesis. Single-cell RNA- and ATAC-Seq analysis reveals that NFI factors repress Shh and Wnt signaling in tanycytes, and small molecule modulation of these pathways blocks proliferation and tanycyte-derived neurogenesis in Nfia/b/x-deficient mice. We show that Nfia/b/x-deficient tanycytes give rise to multiple mediobasal hypothalamic neuronal subtypes that can mature, integrate into hypothalamic synaptic circuitry, and selectively respond to changes in internal states. These findings identify molecular mechanisms that control tanycyte-derived neurogenesis, suggesting a new therapeutic approach to selectively remodel the hypothalamic neural circuitry that controls homeostatic physiological processes.

scholarly journals Control of neurogenic competence in mammalian hypothalamic tanycytes

2021 ◽  
Vol 7 (22) ◽  
pp. eabg3777
Author(s):  
Sooyeon Yoo ◽  
Juhyun Kim ◽  
Pin Lyu ◽  
Thanh V. Hoang ◽  
Alex Ma ◽  
...  
Keyword(s):  
Single Cell ◽  
Molecular Mechanisms ◽  
Radial Glial Cells ◽  
Neuronal Progenitors ◽  
Physiological Processes ◽  
Internal States ◽  
Nuclear Factor I ◽  
Radial Glial ◽  
Accessible Chromatin ◽  
Deficient Mice

Hypothalamic tanycytes, radial glial cells that share many features with neuronal progenitors, can generate small numbers of neurons in the postnatal hypothalamus, but the identity of these neurons and the molecular mechanisms that control tanycyte-derived neurogenesis are unknown. In this study, we show that tanycyte-specific disruption of the NFI family of transcription factors (Nfia/b/x) robustly stimulates tanycyte proliferation and tanycyte-derived neurogenesis. Single-cell RNA sequencing (scRNA-seq) and single-cell assay for transposase-accessible chromatin sequencing (scATAC-seq) analysis reveals that NFI (nuclear factor I) factors repress Sonic hedgehog (Shh) and Wnt signaling in tanycytes and modulation of these pathways blocks proliferation and tanycyte-derived neurogenesis in Nfia/b/x-deficient mice. Nfia/b/x-deficient tanycytes give rise to multiple mediobasal hypothalamic neuronal subtypes that can mature, fire action potentials, receive synaptic inputs, and selectively respond to changes in internal states. These findings identify molecular mechanisms that control tanycyte-derived neurogenesis, which can potentially be targeted to selectively remodel the hypothalamic neural circuitry that controls homeostatic physiological processes.

scholarly journals Dentate gyrus development requires a cortical hem-derived astrocytic scaffold

eLife ◽  
2021 ◽  
Vol 10 ◽  
Author(s):  
Alessia Caramello ◽  
Christophe Galichet ◽  
Karine Rizzoti ◽  
Robin Lovell-Badge
Keyword(s):  
Transcription Factors ◽  
Dentate Gyrus ◽  
Local Network ◽  
Radial Glial Cells ◽  
Neuronal Progenitor ◽  
Neuronal Progenitors ◽  
Radial Glial ◽  
Cortical Hem ◽  
Mouse Brain Development

During embryonic development, radial glial cells give rise to neurons, then to astrocytes following the gliogenic switch. Timely regulation of the switch, operated by several transcription factors, is fundamental for allowing coordinated interactions between neurons and glia. We deleted the gene for one such factor, SOX9, early during mouse brain development and observed a significantly compromised dentate gyrus (DG). We dissected the origin of the defect, targeting embryonic Sox9 deletion to either the DG neuronal progenitor domain or the adjacent cortical hem (CH). We identified in the latter previously uncharacterized ALDH1L1+ astrocytic progenitors, which form a fimbrial-specific glial scaffold necessary for neuronal progenitor migration towards the developing DG. Our results highlight an early crucial role of SOX9 for DG development through regulation of astroglial potential acquisition in the CH. Moreover, we illustrate how formation of a local network, amidst astrocytic and neuronal progenitors originating from adjacent domains, underlays brain morphogenesis.

scholarly journals Dentate gyrus development requires a cortical hem-derived astrocytic scaffold

2020 ◽  
Author(s):  
Alessia Caramello ◽  
Christophe Galichet ◽  
Karine Rizzoti ◽  
Robin Lovell-Badge
Keyword(s):  
Transcription Factors ◽  
Dentate Gyrus ◽  
Local Network ◽  
Radial Glial Cells ◽  
Neuronal Progenitor ◽  
Neuronal Progenitors ◽  
Radial Glial ◽  
Cortical Hem ◽  
Mouse Brain Development

ABSTRACTDuring embryonic development, radial glial cells give rise to neurons, then to astrocytes following the gliogenic switch. Timely regulation of the switch, operated by several transcription factors, is fundamental for allowing coordinated interactions between neurons and glia. We deleted the gene for one such factor, SOX9, early during mouse brain development and observed a significantly compromised dentate gyrus (DG). We dissected the origin of the defect, targeting embryonic Sox9 deletion to either the DG neuronal progenitor domain or the adjacent cortical hem (CH). We identified in the latter previously uncharacterized ALDH1L1+ astrocytic progenitors, which form a fimbrial-specific glial scaffold necessary for neuronal progenitor migration towards the developing DG. Our results highlight an early crucial role of SOX9 for DG development through regulation of astroglial potential acquisition in the CH. Moreover, we illustrate how formation of a local network, amidst astrocytic and neuronal progenitors originating from adjacent domains, underlays brain morphogenesis.

scholarly journals Developmental Genes and Malformations in the Hypothalamus

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.

scholarly journals ANO1/TMEM16A regulates process maturation in radial glial cells in the developing brain

2019 ◽  
Vol 116 (25) ◽  
pp. 12494-12499 ◽  
Author(s):  
Gyu-Sang Hong ◽  
Sung Hoon Lee ◽  
Byeongjun Lee ◽  
Jae Hyouk Choi ◽  
Soo-Jin Oh ◽  
...  
Keyword(s):  
Glial Cells ◽  
Ventricular Zone ◽  
Trophic Factors ◽  
Early Developmental Stage ◽  
Anoctamin 1 ◽  
Radial Glial Cells ◽  
Radial Glial ◽  
Early Developmental ◽  
The Brain ◽  
Deficient Mice

Neural stem cells (NSCs) are primary progenitor cells in the early developmental stage in the brain that initiate a diverse lineage of differentiated neurons and glia. Radial glial cells (RGCs), a type of neural stem cell in the ventricular zone, are essential for nurturing and delivering new immature neurons to the appropriate cortical target layers. Here we report that Anoctamin 1 (ANO1)/TMEM16A, a Ca2+-activated chloride channel, mediates the Ca2+-dependent process extension of RGCs. ANO1 is highly expressed and functionally active in RGCs of the mouse embryonic ventricular zone. Knockdown of ANO1 suppresses RGC process extension and protrusions, whereas ANO1 overexpression stimulates process extension. Among various trophic factors, brain-derived neurotrophic factor (BDNF) activates ANO1, which is required for BDNF-induced process extension in RGCs. More importantly, Ano1-deficient mice exhibited disrupted cortical layers and reduced cortical thickness. We thus conclude that the regulation of RGC process extension by ANO1 contributes to the normal formation of mouse embryonic brain.

scholarly journals CHARACTERISTICS OF miRNA INTERACTION WITH mRNA GENES OF T. AESTIVUM C2H2, ERF, GRAS TRANSCRIPTION FACTORS FAMILIES

2020 ◽  
Vol 2 (338) ◽  
pp. 5-11
Author(s):  
A. K. Rakhmetullina ◽  
S. K. Turasheva ◽  
A. A. Bolshoy ◽  
A. T. Ivashchenko
Keyword(s):  
Transcription Factors ◽  
Binding Sites ◽  
Molecular Mechanisms ◽  
Target Genes ◽  
Abiotic And Biotic Stresses ◽  
Biotic Stresses ◽  
Gras Family ◽  
Physiological Processes ◽  
Nucleotide Interactions

The molecular mechanisms for increasing plant productivity remain poorly understood. Genes of C2H2, GRAS, ERF transcription factors (TFs) families play a key role in the physiological processes of plants, including wheat. In recent years, the important role of miRNAs in the regulation of the expression of many genes involved in the formation of productivity has been established. Wheat miRNA (mRNA-inhibiting RNA) target genes are involved in the regulation of the development of flowers, seeds, root, shoots, and responses to abiotic and biotic stresses. The miRNAs binding sites in mRNAs of C2H2, ERF, GRAS TFs families were performed using the MirTarget program, which calculates the free energy of miRNA binding with mRNA, the schemes and positions of nucleotide interactions with binding sites. Wheat genes were used as the object of the study, since wheat is one of the main grain crops in Kazakhstan and in many other countries. The presence of miRNA binding sites with high nucleotide complementarity in mRNA of C2H2, ERF, GRAS TF genes of wheat was shown. All binding sites of these miRNAs were located in the CDS of mRNA target genes. Of the 125 miRNAs of T. aestivum, miR319-3p efficiently bound with mRNA of C2H2 family genes with the value of ΔG/ΔGm equal 91 %. miR7757-5p interacted with mRNA of ERF and GRAS family genes with the value of ΔG/ΔGm equal to 92 % and 90 % respectively. miR9778-5p bound with mRNA of C2H2, ERF, GRAS family genes to varying degrees. Each of the miR408-3p, miR9780-3p, and miR9778-5p had four target genes with the value of ΔG/ΔGm equal to 87 % and 89 %. These data indicate the dependency of C2H2, GRAS, ERF TFs families expression on miRNA. The obtained results expand the fundamental ideas about the regulatory mechanisms of miRNA in the process of plant growth and development.

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

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.

scholarly journals Molecular Responses during Plant Grafting and Its Regulation by Auxins, Cytokinins, and Gibberellins

Biomolecules ◽  
2019 ◽  
Vol 9 (9) ◽  
pp. 397 ◽  
Author(s):  
Anket Sharma ◽  
Bingsong Zheng
Keyword(s):  
Plant Hormones ◽  
Growth And Development ◽  
Molecular Mechanisms ◽  
Main Process ◽  
Graft Union ◽  
Physiological Processes ◽  
Current Review ◽  
Postharvest Life ◽  
Successful Production

Plant grafting is an important horticulture technique used to produce a new plant after joining rootstock and scion. This is one of the most used techniques by horticulturists to enhance the quality and production of various crops. Grafting helps in improving the health of plants, their yield, and the quality of plant products, along with the enhancement of their postharvest life. The main process responsible for successful production of grafted plants is the connection of vascular tissues. This step determines the success rate of grafts and hence needs to be studied in detail. There are many factors that regulate the connection of scion and stock, and plant hormones are of special interest for researchers in the recent times. These phytohormones act as signaling molecules and have the capability of translocation across the graft union. Plant hormones, mainly auxins, cytokinins, and gibberellins, play a major role in the regulation of various key physiological processes occurring at the grafting site. In the current review, we discuss the molecular mechanisms of graft development and the phytohormone-mediated regulation of the growth and development of graft union.

scholarly journals 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 ◽  
2019 ◽  
Vol 7 (4) ◽  
pp. 76 ◽  
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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