scholarly journals Identifying Novel Roles for Peptidergic Signaling in Mice

2019 ◽  
Author(s):  
Kathryn G. Powers ◽  
Xin-Ming Ma ◽  
Betty A. Eipper ◽  
Richard E. Mains
Keyword(s):  
Gene Expression ◽  
Pain Perception ◽  
Serum Levels ◽  
Tissue Specific ◽  
New Therapeutic Approaches ◽  
Cell Type Specific ◽  
Salt And Water Balance ◽  
Screening Platform ◽  
The Many

ABSTRACTDespite accumulating evidence demonstrating the essential roles played by neuropeptides, it has proven challenging to use this information to develop therapeutic strategies. Peptidergic signaling can involve juxtacrine, paracrine, endocrine and neuronal signaling, making it difficult to define physiologically important pathways. One of the final steps in the biosynthesis of many neuropeptides requires a single enzyme, peptidylglycine α-amidating monooxygenase (PAM), and lack of amidation renders most of these peptides biologically inert. PAM, an ancient integral membrane enzyme that traverses the biosynthetic and endocytic pathways, also affects cytoskeletal organization and gene expression. While mice, zebrafish and flies lackingPam(PamKO/KO) are not viable, we reasoned that cell-type specific elimination ofPamexpression would generate mice that could be screened for physiologically important and tissue-specific deficits.PamcKO/cKOmice, with loxP sites flanking the 2 exons deleted in the globalPamKO/KOmouse, were indistinguishable from wildtype mice. EliminatingPamexpression in excitatory forebrain neurons reduced anxiety-like behavior, increased locomotor responsiveness to cocaine and improved thermoregulation in the cold. A number of amidated peptides play essential roles in each of these behaviors. Although atrial natriuretic peptide (ANP) is not amidated,Pamexpression in the atrium exceeds levels in any other tissue. EliminatingPamexpression in cardiomyocytes increased anxiety-like behavior and improved thermoregulation. Atrial and serum levels of ANP fell sharplyPamMyh6-cKO/cKOin mice and RNASeq analysis identified changes in gene expression in pathways related to cardiac function. Use of this screening platform should facilitate the development of new therapeutic approaches targeted to peptidergic pathways.SIGNIFICANCEPeptidergic signaling, which plays key roles in the many pathways that control thermoregulation, salt and water balance, metabolism, anxiety, pain perception and sexual reproduction, is essential for the maintenance of homeostasis. Despite the fact that peptides generally signal through G protein coupled receptors, it has proven difficult to use knowledge about peptide synthesis, storage and secretion to develop effective therapeutics. Our goal was to develop anin vivobioassay system that would reveal physiologically meaningful deficits associated with disturbed peptidergic signaling. We did so by developing a system in which an enzyme essential for the production of many bioactive peptides could be eliminated in a tissue-specific manner.

scholarly journals Identifying roles for peptidergic signaling in mice

2019 ◽  
Vol 116 (40) ◽  
pp. 20169-20179 ◽  
Author(s):  
Kathryn G. Powers ◽  
Xin-Ming Ma ◽  
Betty A. Eipper ◽  
Richard E. Mains
Keyword(s):  
Gene Expression ◽  
Serum Levels ◽  
Conditional Knockout ◽  
Sequencing Analysis ◽  
Therapeutic Approaches ◽  
Cytoskeletal Organization ◽  
Cell Type Specific ◽  
Screening Platform ◽  
Single Enzyme ◽  
Endocytic Pathways

Despite accumulating evidence demonstrating the essential roles played by neuropeptides, it has proven challenging to use this information to develop therapeutic strategies. Peptidergic signaling can involve juxtacrine, paracrine, endocrine, and neuronal signaling, making it difficult to define physiologically important pathways. One of the final steps in the biosynthesis of many neuropeptides requires a single enzyme, peptidylglycine α-amidating monooxygenase (PAM), and lack of amidation renders most of these peptides biologically inert. PAM, an ancient integral membrane enzyme that traverses the biosynthetic and endocytic pathways, also affects cytoskeletal organization and gene expression. While mice, zebrafish, and flies lacking Pam (PamKO/KO) are not viable, we reasoned that cell type-specific elimination of Pam expression would generate mice that could be screened for physiologically important and tissue-specific deficits. Conditional PamcKO/cKO mice, with loxP sites flanking the 2 exons deleted in the global PamKO/KO mouse, were indistinguishable from wild-type mice. Eliminating Pam expression in excitatory forebrain neurons reduced anxiety-like behavior, increased locomotor responsiveness to cocaine, and improved thermoregulation in the cold. A number of amidated peptides play essential roles in each of these behaviors. Although atrial natriuretic peptide (ANP) is not amidated, Pam expression in the atrium exceeds levels in any other tissue. Eliminating Pam expression in cardiomyocytes increased anxiety-like behavior and improved thermoregulation. Atrial and serum levels of ANP fell sharply in PAM myosin heavy chain 6 conditional knockout mice, and RNA sequencing analysis identified changes in gene expression in pathways related to cardiac function. Use of this screening platform should facilitate the development of therapeutic approaches targeted to peptidergic pathways.

scholarly journals A scalable platform for the development of cell-type-specific viral drivers

eLife ◽  
2019 ◽  
Vol 8 ◽  
Author(s):  
Sinisa Hrvatin ◽  
Christopher P Tzeng ◽  
M Aurel Nagy ◽  
Hume Stroud ◽  
Charalampia Koutsioumpa ◽  
...  
Keyword(s):  
Gene Expression ◽  
Heterologous Gene Expression ◽  
High Specificity ◽  
Cell Types ◽  
Regulatory Elements ◽  
Cell Type ◽  
Cell Type Specificity ◽  
Cell Type Specific ◽  
The Many ◽  
Dna Regulatory Elements

Enhancers are the primary DNA regulatory elements that confer cell type specificity of gene expression. Recent studies characterizing individual enhancers have revealed their potential to direct heterologous gene expression in a highly cell-type-specific manner. However, it has not yet been possible to systematically identify and test the function of enhancers for each of the many cell types in an organism. We have developed PESCA, a scalable and generalizable method that leverages ATAC- and single-cell RNA-sequencing protocols, to characterize cell-type-specific enhancers that should enable genetic access and perturbation of gene function across mammalian cell types. Focusing on the highly heterogeneous mammalian cerebral cortex, we apply PESCA to find enhancers and generate viral reagents capable of accessing and manipulating a subset of somatostatin-expressing cortical interneurons with high specificity. This study demonstrates the utility of this platform for developing new cell-type-specific viral reagents, with significant implications for both basic and translational research.

Human glucagon gene promoter sequences regulating tissue-specific versus nutrient-regulated gene expression

2002 ◽  
Vol 282 (1) ◽  
pp. R173-R183 ◽  
Author(s):  
Min Nian ◽  
Jun Gu ◽  
David M. Irwin ◽  
Daniel J. Drucker
Keyword(s):  
Gene Expression ◽  
Gene Promoter ◽  
Regulatory Sequences ◽  
Dependent Manner ◽  
Specific Expression ◽  
Tissue Specific ◽  
High Fiber ◽  
Fiber Diet ◽  
Regulated Gene Expression

The glucagon-like peptides (GLPs) are synthesized and secreted in a nutrient-dependent manner in rodents; however, the factors regulating human GLP-1 and GLP-2 biosynthesis remain unclear. To understand how nutrients regulate human proglucagon gene expression, we studied the expression of a human proglucagon promoter-growth hormone (GH) transgene in 1.6 human glucagon-GH transgenic mice. Fasting-refeeding significantly decreased and increased the levels of circulating mouse insulin and transgene-derived hGH ( P < 0.05 fasting vs. refeeding) and decreased and upregulated, respectively, the levels of endogenous mouse proglucagon RNA in the ileum but not in the jejunum or colon. High-fiber feeding significantly increased the levels of glucose-stimulated circulating hGH and upregulated levels of mouse intestinal proglucagon gene expression in the jejunum, ileum, and colon ( P < 0.05, 0 vs. 30% fiber diet). In contrast, neither fasting-refeeding nor a high-fiber diet upregulated the expression of the human proglucagon promoter-hGH transgene. These findings demonstrate that human proglucagon gene regulatory sequences specifying tissue-specific expression in gut endocrine cells are not sufficient for recognition of energy-derived signals regulating murine glucagon gene expression in enteroendocrine cells in vivo.

scholarly journals Cell-Type Specific Oxytocin Gene Expression from AAV Delivered Promoter Deletion Constructs into the Rat Supraoptic Nucleus in vivo

PLoS ONE ◽  
2012 ◽  
Vol 7 (2) ◽  
pp. e32085 ◽  
Author(s):  
Raymond L. Fields ◽  
Todd A. Ponzio ◽  
Makoto Kawasaki ◽  
Harold Gainer
Keyword(s):  
Gene Expression ◽  
Supraoptic Nucleus ◽  
Cell Type ◽  
Promoter Deletion ◽  
Cell Type Specific

In Vitro and In Vivo Monitoring of Valproic Acid Effects on Gene Expression Signatures in Adult Acute Myeloid Leukemia.

Blood ◽  
2006 ◽  
Vol 108 (11) ◽  
pp. 2605-2605
Author(s):  
Lars Bullinger ◽  
Konstanze Dohner ◽  
Richard F. Schlenk ◽  
Frank G. Rucker ◽  
Jonathan R. Pollack ◽  
...  
Keyword(s):  
Gene Expression ◽  
Cell Lines ◽  
Myeloid Leukemia ◽  
Leukemia Cell ◽  
Serum Levels ◽  
Leukemia Cell Lines ◽  
Acute Myeloid ◽  
Myeloid Leukemia Cell

Abstract Inhibitors of histone deacetylases (HDACIs) like valproic acid (VPA) display activity in murine leukemia models, and induce tumor-selective cytoxicity against blasts from patients with acute myeloid leukemia (AML). However, despite of the existing knowledge of the potential function of HDACIs, there remain many unsolved questions especially regarding the factors that determine whether a cancer cell undergoes cell cycle arrest, differentiation, or death in response to HDACIs. Furthermore, there is still limited data on HDACIs effects in vivo, as well as HDACIs function in combination with standard induction chemotherapy, as most studies evaluated HDACIs as single agent in vitro. Thus, our first goal was to determine a VPA response signature in different myeloid leukemia cell lines in vitro, followed by an in vivo analysis of VPA effects in blasts from adult de novo AML patients entered within two randomized multicenter treatment trials of the German-Austrian AML Study Group. To define an VPA in vitro “response signature” we profiled gene expression in myeloid leukemia cell lines (HL-60, NB-4, HEL-1, CMK and K-562) following 48 hours of VPA treatment by using DNA Microarray technology. In accordance with previous studies in vitro VPA treatment of myeloid cell lines induced the expression of the cyclin-dependent kinase inhibitors CDKN1A and CDKN2D coding for p21 and p19, respectively. Supervised analyses revealed many genes known to be associated with a G1 arrest. In all cell lines except for CMK we examined an up-regulation of TNFSF10 coding for TRAIL, as well as differential regulation of other genes involved in apoptosis. Furthermore, gene set enrichment analyses showed a significant down-regulation of genes involved in DNA metabolism and DNA repair. Next, we evaluated the VPA effects on gene expression in AML samples collected within the AMLSG 07-04 trial for younger (age<60yrs) and within the AMLSG 06-04 trial for older adults (age>60yrs), in which patients are randomized to receive standard induction chemotherapy (idarubicine, cytarabine, and etoposide = ICE) with or without concomitant VPA. We profiled gene expression in diagnostic AML blasts and following 48 hours of treatment with ICE or ICE/VPA. First results from our ongoing analysis of in vivo VPA treated samples are in accordance with our cell line experiments as e.g. we also see an induction of CDKN1A expression. However, the picture observed is less homogenous as concomitant administration of ICE, as well as other factors, like e.g. VPA serum levels, might substantially influence the in vivo VPA response. Nevertheless, our data are likely to provide new insights into the VPA effect in vivo, and this study may proof to be useful to predict AML patients likely to benefit from VPA treatment. To achieve this goal, we are currently analyzing additional samples, and we are planning to correlate gene expression findings with histone acetylation status, VPA serum levels, cytogenetic, and molecular genetic data.

scholarly journals Noninvasive in vivo monitoring of tissue-specific global gene expression in humans

2014 ◽  
Vol 111 (20) ◽  
pp. 7361-7366 ◽  
Author(s):  
W. Koh ◽  
W. Pan ◽  
C. Gawad ◽  
H. C. Fan ◽  
G. A. Kerchner ◽  
...  
Keyword(s):  
Gene Expression ◽  
Global Gene Expression ◽  
Tissue Specific ◽  
In Vivo Monitoring

scholarly journals Determination of tissue-specific interaction between vitamin C and vitamin E in vivo using senescence marker protein-30 knockout mice as a vitamin C synthesis deficiency model

2021 ◽  
pp. 1-33
Author(s):  
Ayami Sato ◽  
Yuka Takino ◽  
Tomohiro Yano ◽  
Koji Fukui ◽  
Akihito Ishigami
Keyword(s):  
Gene Expression ◽  
Vitamin E ◽  
Vitamin C ◽  
Specific Interaction ◽  
Marker Protein ◽  
Tissue Specific ◽  
Transfer Protein

Abstract Vitamin E (α-tocopherol; VE) is known to be regenerated from VE radicals by vitamin C (L-ascorbic acid; VC) in vitro. However, their in vivo interaction in various tissues is still unclear. Therefore, we alternatively examined the in vivo interaction of VC and VE by measurement of their concentrations in various tissues of senescence marker protein-30 (SMP30) knockout (KO) mice as a VC synthesis deficiency model. Male SMP30-KO mice were divided into four groups (VC+/VE+, VC+/VE-, VC-/VE+, and VC-/VE-), fed diets with or without 500 mg/kg VE and given water with or without 1.5 g/L VC ad libitum. Then, VC and VE concentrations in the plasma and various tissues were determined. Further, gene expression levels of transporters associated with VC and VE, such as α-tocopherol transfer protein (α-TTP) and sodium-dependent vitamin C transporters (SVCTs), were examined. These results showed that the VE levels in the VC-depleted (VC-/VE+) group were significantly lower than those in the VC+/VE+ group in the liver and heart; the VC levels in the VE-depleted (VC+/VE-) group were significantly lower than those in the VC+/VE+ group in the kidneys. The α-TTP gene expression in the liver and kidneys were decreased by VC and/or VE depletion. Moreover, SVCT1 gene expression in the liver was decreased by both VC and VE depletion. In conclusion, these results indicate that VC spares VE mainly in the liver and heart, and that VE spares VC in the kidneys of SMP30-KO mice. Thus, interaction between VC and VE is likely to be tissue specific.

scholarly journals Inherited Chromosomally Integrated Human Herpesvirus 6 Demonstrates Tissue-Specific RNA Expression In Vivo That Correlates with an Increased Antibody Immune Response

2019 ◽  
Vol 94 (1) ◽  
Author(s):  
Vikas Peddu ◽  
Isabelle Dubuc ◽  
Annie Gravel ◽  
Hong Xie ◽  
Meei-Li Huang ◽  
...  
Keyword(s):  
Gene Expression ◽  
Specific Antibody ◽  
Human Herpesvirus ◽  
Specific Gene ◽  
Specific Antibody Response ◽  
Tissue Specific ◽  
Tissue Specific Gene ◽  
Specific Gene Expression ◽  
Human Herpesviruses

ABSTRACT Human herpesviruses 6A and 6B (HHV-6A and HHV-6B) are human viruses capable of chromosomal integration. Approximately 1% of the human population carries one copy of HHV-6A/B integrated into every cell in their body, referred to as inherited chromosomally integrated human herpesvirus 6A/B (iciHHV-6A/B). Whether iciHHV-6A/B is transcriptionally active in vivo and how it shapes the immunological response are still unclear. In this study, we screened DNA sequencing (DNA-seq) and transcriptome sequencing (RNA-seq) data for 650 individuals available through the Genotype-Tissue Expression (GTEx) project and identified 2 iciHHV-6A- and 4 iciHHV-6B-positive candidates. When corresponding tissue-specific gene expression signatures were analyzed, low levels HHV-6A/B gene expression was found across multiple tissues, with the highest levels of gene expression in the brain (specifically for HHV-6A), testis, esophagus, and adrenal gland. U90 and U100 were the most highly expressed HHV-6 genes in both iciHHV-6A- and iciHHV-6B-positive individuals. To assess whether tissue-specific gene expression from iciHHV-6A/B influences the immune response, a cohort of 15,498 subjects was screened and 85 iciHHV-6A/B+ subjects were identified. Plasma samples from iciHHV-6A/B+ and age- and sex-matched controls were analyzed for antibodies to control antigens (cytomegalovirus [CMV], Epstein-Barr virus [EBV], and influenza virus [FLU]) or HHV-6A/B antigens. Our results indicate that iciHHV-6A/B+ subjects have significantly more antibodies against the U90 gene product (IE1) than do non-iciHHV-6-positive individuals. Antibody responses against EBV and FLU antigens or HHV-6A/B gene products either not expressed or expressed at low levels, such as U47, U57, and U72, were identical between controls and iciHHV-6A/B+ subjects. CMV-seropositive individuals with iciHHV-6A/B+ have more antibodies against CMV pp150 than do CMV-seropositive controls. These results argue that spontaneous gene expression from integrated HHV-6A/B leads to an increase in antigenic burden that translates into a more robust HHV-6A/B-specific antibody response. IMPORTANCE HHV-6A and -6B are human herpesviruses that have the unique property of being able to integrate into the telomeric regions of human chromosomes. Approximately 1% of the world’s population carries integrated HHV-6A/B genome in every cell of their body. Whether viral genes are transcriptionally active in these individuals is unclear. By taking advantage of a unique tissue-specific gene expression data set, we showed that the majority of tissues from iciHHV-6 individuals do not show HHV-6 gene expression. Brain and testes showed the highest tissue-specific expression of HHV-6 genes in two separate data sets. Two HHV-6 genes, U90 (immediate early 1 protein) and U100 (glycoproteins Q1 and Q2), were found to be selectively and consistently expressed across several human tissues. Expression of U90 translates into an increase in antigen-specific antibody response in iciHHV-6A/B+ subjects relative to controls. Future studies will be needed to determine the mechanism of gene expression, the effects of these genes on human gene transcription networks, and the pathophysiological impact of having increased viral protein expression in tissue in conjunction with increased antigen-specific antibody production.

Differentiation: the selective potentiation of chromatin domains

Development ◽  
1998 ◽  
Vol 125 (23) ◽  
pp. 4749-4755 ◽  
Author(s):  
J.A. Kramer ◽  
J.R. McCarrey ◽  
D. Djakiew ◽  
S.A. Krawetz
Keyword(s):  
Gene Expression ◽  
Stem Cell ◽  
Spermatogonial Stem Cell ◽  
Specific Gene ◽  
Cell Type ◽  
Chromatin Domains ◽  
Tissue Specific ◽  
Specific Gene Expression ◽  
Cell Type Specific ◽  
Cellular Phenotypes

Potentiation is requisite for the expression of our genome. It is the mechanism of opening chromatin domains to render genes accessible to tissue-specific and ubiquitous transacting-factors that enables transcription. The results presented in this study demonstrate that modulation of stage- and cell-type-specific gene expression during mammalian spermatogenesis involves selective potentiation of testis-expressed genes that reverses their repressive state when present in the spermatogonial stem cell. This directly contrasts hematopoiesis, which acts to selectively restrict lineage potential during differentiation from its permissive stem cell. These results are key to understanding how differentiative pathways are controlled and cellular phenotypes determined. A window to their modulation is presented.

scholarly journals Diet-Derived Polyphenol Metabolite Enterolactone Is a Tissue-Specific Estrogen Receptor Activator

Endocrinology ◽  
2007 ◽  
Vol 148 (10) ◽  
pp. 4875-4886 ◽  
Author(s):  
Pauliina Penttinen ◽  
Jan Jaehrling ◽  
Anastasios E. Damdimopoulos ◽  
José Inzunza ◽  
Josephine G. Lemmen ◽  
...  
Keyword(s):  
Gene Expression ◽  
Ligand Binding ◽  
Estrogenic Activity ◽  
Culture Conditions ◽  
Mouse Uterus ◽  
Tissue Specific ◽  
Dietary Polyphenols ◽  
Reporter Mice

Numerous dietary compounds can modify gene expression by binding to the members of the nuclear receptor superfamily of transcription factors. For example, dietary polyphenols, such as soy isoflavones genistein and daidzein, modulate the activity of the estrogen receptors (ERs)-α and ERβ. An additional class of dietary polyphenols that modulate cellular signaling pathways are lignans, compounds that are common constituents of Western diets. In this study, we show that a metabolite of dietary lignans, enterolactone, at physiological concentrations, activates ER-mediated transcription in vitro with preference for ERα. The effects of enterolactone are mediated by the ER ligand binding domain and are susceptible to antiestrogen treatment. Furthermore, the affinity of enterolactone toward ERα, measured by a novel ligand binding assay, is augmented in cell culture conditions. Moreover, our results demonstrate for the first time that enterolactone has estrogenic activity in vivo. In transgenic estrogen-sensitive reporter mice, enterolactone induces tissue-specific estrogen-responsive reporter gene expression as well as promotes uterine stromal edema and expression of estrogen-responsive endogenous genes (CyclinD1 and Ki67). Taken together, our data show that enterolactone is a selective ER agonist inducing ER-mediated transcription both in vitro in different cell lines and in vivo in the mouse uterus.

Sign in / Sign up

Export Citation Format

Share Document