scholarly journals CRISPR-mediated activation of a promoter or enhancer rescues obesity caused by haploinsufficiency

Science ◽  
2018 ◽  
Vol 363 (6424) ◽  
pp. eaau0629 ◽  
Author(s):  
Navneet Matharu ◽  
Sawitree Rattanasopha ◽  
Serena Tamura ◽  
Lenka Maliskova ◽  
Yi Wang ◽  
...  
Keyword(s):  
Therapeutic Potential ◽  
Gene Dosage ◽  
Adeno Associated Virus ◽  
Endogenous Gene ◽  
Gene Copies ◽  
Wide Range ◽  
Obesity Phenotype ◽  
Potential Strategy ◽  
Altered Gene ◽  
Functional Copy

A wide range of human diseases result from haploinsufficiency, where the function of one of the two gene copies is lost. Here, we targeted the remaining functional copy of a haploinsufficient gene using CRISPR-mediated activation (CRISPRa) in Sim1 and Mc4r heterozygous mouse models to rescue their obesity phenotype. Transgenic-based CRISPRa targeting of the Sim1 promoter or its distant hypothalamic enhancer up-regulated its expression from the endogenous functional allele in a tissue-specific manner, rescuing the obesity phenotype in Sim1 heterozygous mice. To evaluate the therapeutic potential of CRISPRa, we injected CRISPRa-recombinant adeno-associated virus into the hypothalamus, which led to reversal of the obesity phenotype in Sim1 and Mc4r haploinsufficient mice. Our results suggest that endogenous gene up-regulation could be a potential strategy to treat altered gene dosage diseases.

scholarly journals Promoter or enhancer activation by CRISPRa rescues haploinsufficiency caused obesity

2017 ◽  
Author(s):  
Navneet Matharu ◽  
Sawitree Rattanasopha ◽  
Lenka Maliskova ◽  
Yi Wang ◽  
Aaron Hardin ◽  
...  
Keyword(s):  
Therapeutic Strategy ◽  
Gene Dosage ◽  
Regulatory Elements ◽  
Adeno Associated Virus ◽  
Wide Range ◽  
Obesity Phenotype ◽  
Altered Gene ◽  
Functional Copy ◽  
Crispr Activation

AbstractHaploinsufficiency, having only one functional copy of a gene, leads to a wide range of human disease and has been associated with over 300 genes. Here, we tested whether CRISPR activation (CRISPRa) could rescue a haploinsufficient disease in vivo. Haploinsufficiency of Sim1, a transcription factor involved in the leptin pathway, results in severe obesity in humans and mice. CRISPRa targeting of either the Sim1 promoter or its ~270kb distant hypothalamic enhancer using transgenic mice, rescued the obesity phenotype in Sim1 heterozygous mice. Interestingly, despite using a ubiquitous promoter for CRISPRa, Sim1 was upregulated only in tissues where the promoter or enhancer are active, suggesting that cis-regulatory elements can determine CRISPRa tissue-specificity. To further relate this to therapy, we injected CRISPRa adeno associated virus into the hypothalamus, leading to reversal of the obesity phenotype. This therapeutic strategy could be used to rescue numerous diseases resulting from altered gene dosage.

Isoform-Selective PI3K Inhibitors for Various Diseases

2020 ◽  
Vol 20 (12) ◽  
pp. 1074-1092 ◽  
Author(s):  
Rammohan R.Y. Bheemanaboina
Keyword(s):  
Intracellular Signaling ◽  
Kinase Inhibitors ◽  
Therapeutic Potential ◽  
Type I ◽  
Selective Inhibitors ◽  
Pi3k Inhibitors ◽  
Wide Range ◽  
Lipid Kinases ◽  
Isoform Selectivity

Phosphoinositide 3-kinases (PI3Ks) are a family of ubiquitously distributed lipid kinases that control a wide variety of intracellular signaling pathways. Over the years, PI3K has emerged as an attractive target for the development of novel pharmaceuticals to treat cancer and various other diseases. In the last five years, four of the PI3K inhibitors viz. Idelalisib, Copanlisib, Duvelisib, and Alpelisib were approved by the FDA for the treatment of different types of cancer and several other PI3K inhibitors are currently under active clinical development. So far clinical candidates are non-selective kinase inhibitors with various off-target liabilities due to cross-reactivities. Hence, there is a need for the discovery of isoform-selective inhibitors with improved efficacy and fewer side-effects. The development of isoform-selective inhibitors is essential to reveal the unique functions of each isoform and its corresponding therapeutic potential. Although the clinical effect and relative benefit of pan and isoformselective inhibition will ultimately be determined, with the development of drug resistance and the demand for next-generation inhibitors, it will continue to be of great significance to understand the potential mechanism of isoform-selectivity. Because of the important role of type I PI3K family members in various pathophysiological processes, isoform-selective PI3K inhibitors may ultimately have considerable efficacy in a wide range of human diseases. This review summarizes the progress of isoformselective PI3K inhibitors in preclinical and early clinical studies for anticancer and other various diseases.

scholarly journals A Haplolethal Locus Uncovered by Deletions in the Mouse t Complex

Genetics ◽  
2002 ◽  
Vol 160 (2) ◽  
pp. 675-682
Author(s):  
Victoria L Browning ◽  
Rebecca A Bergstrom ◽  
Sandra Daigle ◽  
John C Schimenti
Keyword(s):  
Gene Dosage ◽  
Es Cells ◽  
Embryonic Stem ◽  
Chromosome 17 ◽  
Mammalian Development ◽  
T Complex ◽  
Segmental Aneuploidy ◽  
Systematic Exploration ◽  
Radiation Induced ◽  
Altered Gene

Abstract Proper levels of gene expression are important for normal mammalian development. Typically, altered gene dosage caused by karyotypic abnormalities results in embryonic lethality or birth defects. Segmental aneuploidy can be compatible with life but often results in contiguous gene syndromes. The ability to manipulate the mouse genome allows the systematic exploration of regions that are affected by alterations in gene dosage. To explore the effects of segmental haploidy in the mouse t complex on chromosome 17, radiation-induced deletion complexes centered at the Sod2 and D17Leh94 loci were generated in embryonic stem (ES) cells. A small interval was identified that, when hemizygous, caused specific embryonic lethal phenotypes (exencephaly and edema) in most fetuses. The penetrance of these phenotypes was background dependent. Additionally, evidence for parent-of-origin effects was observed. This genetic approach should be useful for identifying genes that are imprinted or whose dosage is critical for normal embryonic development.

scholarly journals Bioactive potential of natural biomaterials: identification, retention and assessment of biological properties

2021 ◽  
Vol 6 (1) ◽  
Author(s):  
Kieran Joyce ◽  
Georgina Targa Fabra ◽  
Yagmur Bozkurt ◽  
Abhay Pandit
Keyword(s):  
Tissue Engineering ◽  
Therapeutic Potential ◽  
Biological Properties ◽  
Biological Assessment ◽  
Cross Linking ◽  
Natural Polymers ◽  
Drug Delivery Device ◽  
Biomedical Device ◽  
Wide Range ◽  
Bioactive Potential

AbstractBiomaterials have had an increasingly important role in recent decades, in biomedical device design and the development of tissue engineering solutions for cell delivery, drug delivery, device integration, tissue replacement, and more. There is an increasing trend in tissue engineering to use natural substrates, such as macromolecules native to plants and animals to improve the biocompatibility and biodegradability of delivered materials. At the same time, these materials have favourable mechanical properties and often considered to be biologically inert. More importantly, these macromolecules possess innate functions and properties due to their unique chemical composition and structure, which increase their bioactivity and therapeutic potential in a wide range of applications. While much focus has been on integrating these materials into these devices via a spectrum of cross-linking mechanisms, little attention is drawn to residual bioactivity that is often hampered during isolation, purification, and production processes. Herein, we discuss methods of initial material characterisation to determine innate bioactivity, means of material processing including cross-linking, decellularisation, and purification techniques and finally, a biological assessment of retained bioactivity of a final product. This review aims to address considerations for biomaterials design from natural polymers, through the optimisation and preservation of bioactive components that maximise the inherent bioactive potency of the substrate to promote tissue regeneration.

Smith–Magenis syndrome: haploinsufficiency of RAI1 results in altered gene regulation in neurological and metabolic pathways

2011 ◽  
Vol 13 ◽  
Author(s):  
Sarah H. Elsea ◽  
Stephen R. Williams
Keyword(s):  
Metabolic Pathways ◽  
Gene Dosage ◽  
Therapeutic Strategies ◽  
Molecular Evidence ◽  
Diagnostic Strategies ◽  
Functional Studies ◽  
Molecular Features ◽  
Altered Gene ◽  
Behavioural Management

Smith–Magenis syndrome (SMS) is a complex neurobehavioural disorder characterised by intellectual disability, self-injurious behaviours, sleep disturbance, obesity, and craniofacial and skeletal anomalies. Diagnostic strategies are focused towards identification of a 17p11.2 microdeletion encompassing the gene RAI1 (retinoic acid induced 1) or a mutation of RAI1. Molecular evidence shows that most SMS features are due to RAI1 haploinsufficiency, whereas variability and severity are modified by other genes in the 17p11.2 region for 17p11.2 deletion cases. The functional role of RAI1 is not completely understood, but it is probably a transcription factor acting in several different biological pathways that are dysregulated in SMS. Functional studies based on the hypothesis that RAI1 acts through phenotype-specific pathways involving several downstream genes have shown that RAI1 gene dosage is crucial for normal regulation of circadian rhythm, lipid metabolism and neurotransmitter function. Here, we review the clinical and molecular features of SMS and explore more recent studies supporting possible therapeutic strategies for behavioural management.

Targeted chemical nucleases have a wide range of untapped applications in biological fields, including gene therapy

2021 ◽  
Author(s):  
Moataz Dowaidar
Keyword(s):  
Metal Complex ◽  
Dna Cleavage ◽  
Therapeutic Potential ◽  
Chemical Reactivity ◽  
Major Groove ◽  
Sequence Recognition ◽  
Wide Range ◽  
Chemical Nucleases

A feasible alternative to state-of-the-art enzymatic nucleases was created by regulating the cleavage activity of metal complexes using (covalent or non-covalent) homing agents. Targeted AMNs, unlike enzymatic nucleases, break DNA by an oxidative mechanism and can therefore permanently knock off genes. Compared to larger enzymatic nucleases, the modest size of the metal complex may aid cellular transfection. Furthermore, the painstaking construction of the sequence-specific probe permits a metal complex to be directed to dsDNA's minor or major groove. To direct the chemical reactivity of several small-molecule compounds to dsDNA's minor groove, covalently bonded polyamide samples were used. PNA and DNA were also used to construct antisense and antigen hybrids, with Watson–Crick or Hoogsteen base pairing with major groove nucleobases giving sequence recognition. Click chemistry created chimeric AMN-TFOs with desirable focused effects and negligible off-target cleavage. Clip-Phen-modified TFOs, 230 polypyridyl-modified TFOs, 232 and intercalating phenanthrene-modified TFOs are three contemporary instances of copper AMN–TFOs. All three systems have distinct advantages in maintaining the desired 2:1 phenthroline/copper ratio for DNA cleavage (clip-Phen TFOs), caging the copper center and facilitating efficient ROS-mediated strand scission (polypyridyl-modified TFO) and improving triplex stability (polypyridyl-modified TFO) (phenanthrene-TFOs). Cerium (IV)/EDTA complexes, recently shown to bind and hydrolytically cleave ssDNA/dsDNA junctions and used in conjunction with PNA to successfully introduce genome changes in vitro and in vivo, are another important class of targeted chemical nucleases. The chemical reactivity and wide flexibility of metal complex design, combined with their coupling to sequence specific samples for directed applications, show that these compounds have a wide range of untapped applications in biological fields such as chemotherapy, protein engineering, DNA footprinting, and gene editing. Parallel advancements in cell and tissue targeting will be essential to maximise their therapeutic potential, either by using specific ligands or creating new targeting modalities.

scholarly journals New Pharmacological Opportunities for Betulinic Acid

Planta Medica ◽  
2017 ◽  
Vol 84 (01) ◽  
pp. 8-19 ◽  
Author(s):  
José Ríos ◽  
Salvador Máñez
Keyword(s):  
Metabolic Syndrome ◽  
Natural Product ◽  
Betulinic Acid ◽  
Therapeutic Potential ◽  
Present Review ◽  
Antitumor Effects ◽  
Pharmacological Activities ◽  
Naturally Occurring ◽  
Wide Range ◽  
Birch Trees

AbstractBetulinic acid is a naturally occurring pentacyclic lupane-type triterpenoid usually isolated from birch trees, but present in many other botanical sources. It is found in different plant organs, both as a free aglycon and as glycosyl derivatives. A wide range of pharmacological activities has been described for this triterpenoid, including antiviral and antitumor effects. In addition, several other interesting properties have been identified in the fields of immunity and metabolism, namely antidiabetic, antihyperlipidemic, and anti-inflammatory activities. Taken together, these latter three properties make betulinic acid a highly interesting prospect for treating metabolic syndrome. The present review focuses on the therapeutic potential of this agent, along with several of its semisynthetic derivatives, which could open new frontiers in the use of natural product-based medicines.

scholarly journals How environment shapes horizontal gene transfer

2020 ◽  
Vol 2 (7A) ◽  
Author(s):  
Rama Bhatia ◽  
Hande Kirit ◽  
Jonathan Bollback
Keyword(s):  
Gene Transfer ◽  
Horizontal Gene Transfer ◽  
Gene Dosage ◽  
Recipient Cell ◽  
Endogenous Gene ◽  
Fitness Effects ◽  
Serovar Typhimurium ◽  
A Cell ◽  
Evolutionary Fate

The evolutionary fate of a horizontal gene transfer (HGT) event is determined by its fitness on the recipient cell, i.e., whether it is beneficial, neutral or deleterious. The distribution of fitness effects (DFE), thus is a fundamental predictor of the outcome of an HGT event. The environment plays a considerable role in determining the fitness cost of a horizontally transferred gene. We have studied the fitness effects of genes transferred from Salmonella enterica serovar Typhimurium to Escherichia coli in six environments, that potentially represent the conditions experienced by the two species. The data suggests high variability of genes in different environments. Genes, whose fitness varies substantially between environments, may be able to persist in populations while being deleterious in one environment, they may be neutral or even beneficial in another environment, suggesting that environmental fluctuations may increase the likelihood of HGT. In addition to the in vitro environments, we are also looking at, how changes in the intrinsic environment of a cell, after an HGT event, could affect fitness. An increase in protein dosage due to functional similarity of the horizontally transferred gene to the endogenous gene can cause an imbalance in the cell, thereby leading to a negative fitness effect. By comparing the growth rates of each ortholog gene with the wild type strain, we can elucidate when gene dosage acts as a barrier to HGT.

scholarly journals Zanjabeel (Zingiber officinale Roscoe.): An Evidence-Based Review of Anti-nociceptive, Anti-inflammatory, Antioxidant, and Antimicrobial Properties

2021 ◽  
pp. 26-35
Author(s):  
Fatima Khan ◽  
Mohd Nayab ◽  
Abdul Nasir Ansari
Keyword(s):  
Therapeutic Potential ◽  
Antioxidant Properties ◽  
Plant Secondary Metabolites ◽  
Zingiber Officinale ◽  
Extensive Study ◽  
The Body ◽  
Wide Range ◽  
Zingiber Officinale Roscoe ◽  
Medicinal Properties ◽  
Anti Inflammatory

Ginger has been appreciated for over 2500-3000 years in many parts of the world due to its numerous scientific properties. The ginger plant (Zingiber officinale Roscoe) belongs to the Zingiberaceae family. It is a known food and flavoring ingredient reputed for its wide range of medicinal properties that have been widely used in Chinese, Ayurvedic, and Unāni Tibb worldwide, since antiquity. Ginger has long been used to cure a variety of ailments, including diarrhea, stomach discomfort, indigestion, and nausea. It is a versatile herb with phenomenal phytotherapeutic and medicinal properties. Active ingredients available in ginger such as 6-gingerol, 6-shogaol, 6-paradol, and zingerone are responsible for upgrading enzyme actions and balancing circulation through rejuvenating the body with physical re-strengthening. Gingerols, the key phenolic plant secondary metabolites responsible for its distinct flavor and health benefits, are found in the rhizome of ginger Extensive study has been undertaken over the last two decades to uncover bioactive ingredients and the therapeutic potential of ginger. This review considers ginger's chemical composition and the most recent study findings on its possible health advantages, such as analgesic, anti-inflammatory, antibacterial, and antioxidant properties due to its phytochemistry. Overall, clinical trials are needed to confirm these prospective various health advantages of ginger in human subjects and the most efficacious dosage, based on the current body of scientific literature.

Diverse developmental mutants revealed in an activation-tagged population of poplarThis article is one of a selection of papers published on the Special Issue of Poplar Research in Canada.

2007 ◽  
Vol 85 (11) ◽  
pp. 1071-1081 ◽  
Author(s):  
Edward J. Harrison ◽  
Michael Bush ◽  
Jonathan M. Plett ◽  
Daniel P. McPhee ◽  
Robin Vitez ◽  
...  
Keyword(s):  
Large Scale ◽  
Insertional Mutagenesis ◽  
Hybrid Poplar ◽  
Activation Tagging ◽  
Developmental Abnormalities ◽  
Endogenous Gene ◽  
Developmental Mutants ◽  
Poplar Trees ◽  
Wide Range ◽  
Mutant Lines

We have produced the largest population of activation-tagged poplar trees to date, approximately 1800 independent lines, and report on phenotypes of interest that have been identified in tissue culture and greenhouse conditions. Activation tagging is an insertional mutagenesis technique that results in the dominant upregulation of an endogenous gene. A large-scale Agrobacterium -mediated transformation protocol was used to transform the pSKI074 activation-tagging vector into Populus tremula × Populus alba hybrid poplar. We have screened the first 1000 lines for developmental abnormalities and have a visible mutant frequency of 2.4%, with alterations in leaf and stem structure as well as overall stature. Most of the phenotypes represent new phenotypes that have not previously been identified in poplar and, in some cases, not in any other plant either. Molecular analysis of the T-DNA inserts of a subpopulation of mutant lines reveal both single and double T-DNA inserts with double inserts more common in lines with visible phenotypes. The broad range of developmental mutants identified in this pilot screen of the population reveals that it will be a valuable resource for gene discovery in poplar. The full value of this population will only be realized as we screen these lines for a wide range of phenotypes.

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