Evidence for Site- and Domain-Specific Phosphorylation of the 145-kDa Neurofilament Subunit In Vivo

1991 ◽  
pp. 465-469
Author(s):  
Ram K. Sihag ◽  
Ralph A. Nixon
Keyword(s):  
Domain Specific

scholarly journals Selective Targeting of Epigenetic Readers and Histone Deacetylases in Autoimmune and Inflammatory Diseases: Recent Advances and Future Perspectives

2021 ◽  
Vol 11 (5) ◽  
pp. 336
Author(s):  
Mohammed Ghiboub ◽  
Ahmed M. I. Elfiky ◽  
Menno P. J. de Winther ◽  
Nicola R. Harker ◽  
David F. Tough ◽  
...  
Keyword(s):  
Histone Deacetylases ◽  
Inflammatory Diseases ◽  
Selective Inhibition ◽  
In Vivo Studies ◽  
Beneficial Effects ◽  
Domain Specific ◽  
Recent Advances ◽  
Autoimmune And Inflammatory Diseases

Histone deacetylases (HDACs) and bromodomain-containing proteins (BCPs) play a key role in chromatin remodeling. Based on their ability to regulate inducible gene expression in the context of inflammation and cancer, HDACs and BCPs have been the focus of drug discovery efforts, and numerous small-molecule inhibitors have been developed. However, dose-limiting toxicities of the first generation of inhibitors, which typically target multiple HDACs or BCPs, have limited translation to the clinic. Over the last decade, an increasing effort has been dedicated to designing class-, isoform-, or domain-specific HDAC or BCP inhibitors, as well as developing strategies for cell-specific targeted drug delivery. Selective inhibition of the epigenetic modulators is helping to elucidate the functions of individual epigenetic proteins and has the potential to yield better and safer therapeutic strategies. In accordance with this idea, several in vitro and in vivo studies have reported the ability of more selective HDAC/BCP inhibitors to recapitulate the beneficial effects of pan-inhibitors with less unwanted adverse events. In this review, we summarize the most recent advances with these strategies, discussing advantages and limitations of these approaches as well as some therapeutic perspectives, focusing on autoimmune and inflammatory diseases.

scholarly journals Escape of HIV-1 is associated with lack of V3 domain-specific antibodies in vivo

1997 ◽  
Vol 107 (1) ◽  
pp. 15-20 ◽  
Author(s):  
M. SCHREIBER ◽  
H. MULLER ◽  
C. WACHSMUTH ◽  
T. LAUE ◽  
F. T. HUFERT ◽  
...  
Keyword(s):  
Specific Antibodies ◽  
Domain Specific ◽  
Hiv 1

scholarly journals Distinctive binding properties of human monoclonal LGI1 autoantibodies determine pathogenic mechanisms

Brain ◽  
2020 ◽  
Vol 143 (6) ◽  
pp. 1731-1745 ◽  
Author(s):  
Melanie Ramberger ◽  
Antonio Berretta ◽  
Jeanne M M Tan ◽  
Bo Sun ◽  
Sophia Michael ◽  
...  
Keyword(s):  
Hippocampal Neurons ◽  
Molecular Mechanisms ◽  
Long Term Potentiation ◽  
Serum Samples ◽  
Pathogenic Potential ◽  
Binding Characteristics ◽  
Domain Specific ◽  
Rodent Brain ◽  
Specific Memory

Abstract Autoantibodies against leucine-rich glioma inactivated 1 (LGI1) are found in patients with limbic encephalitis and focal seizures. Here, we generate patient-derived monoclonal antibodies (mAbs) against LGI1. We explore their sequences and binding characteristics, plus their pathogenic potential using transfected HEK293T cells, rodent neuronal preparations, and behavioural and electrophysiological assessments in vivo after mAb injections into the rodent hippocampus. In live cell-based assays, LGI1 epitope recognition was examined with patient sera (n = 31), CSFs (n = 11), longitudinal serum samples (n = 15), and using mAbs (n = 14) generated from peripheral B cells of two patients. All sera and 9/11 CSFs bound both the leucine-rich repeat (LRR) and the epitempin repeat (EPTP) domains of LGI1, with stable ratios of LRR:EPTP antibody levels over time. By contrast, the mAbs derived from both patients recognized either the LRR or EPTP domain. mAbs against both domain specificities showed varied binding strengths, and marked genetic heterogeneity, with high mutation frequencies. LRR-specific mAbs recognized LGI1 docked to its interaction partners, ADAM22 and ADAM23, bound to rodent brain sections, and induced internalization of the LGI1-ADAM22/23 complex in both HEK293T cells and live hippocampal neurons. By contrast, few EPTP-specific mAbs bound to rodent brain sections or ADAM22/23-docked LGI1, but all inhibited the docking of LGI1 to ADAM22/23. After intrahippocampal injection, and by contrast to the LRR-directed mAbs, the EPTP-directed mAbs showed far less avid binding to brain tissue and were consistently detected in the serum. Post-injection, both domain-specific mAbs abrogated long-term potentiation induction, and LRR-directed antibodies with higher binding strengths induced memory impairment. Taken together, two largely dichotomous populations of LGI1 mAbs with distinct domain binding characteristics exist in the affinity matured peripheral autoantigen-specific memory pools of individuals, both of which have pathogenic potential. In human autoantibody-mediated diseases, the detailed characterization of patient mAbs provides a valuable method to dissect the molecular mechanisms within polyclonal populations.

scholarly journals Analysis of novel domain-specific mutations in the zebrafish ndr2/cyclops gene generated using CRISPR-Cas9 RNPs

2018 ◽  
Author(s):  
Ashley N. Turner ◽  
Reagan S. Andersen ◽  
Ivy E. Bookout ◽  
Lauren N. Brashear ◽  
James C. Davis ◽  
...  
Keyword(s):  
Central Nervous System ◽  
Nervous System ◽  
Transforming Growth Factor ◽  
A Priori ◽  
Chemical Mutagenesis ◽  
Sequence Information ◽  
Small Indels ◽  
Domain Specific

AbstractNodal-related protein (ndr2) is a member of the transforming growth factor type β superfamily of factors and is required for ventral midline patterning of the embryonic central nervous system in zebrafish. In humans, mutations in the gene encoding nodal cause holoprosencephaly and heterotaxy. Mutations in the ndr2 gene in the zebrafish (Danio rerio) lead to similar phenotypes, including loss of the medial floor plate, severe deficits in ventral forebrain development, and cyclopia. Alleles of the ndr2 gene have been useful in studying patterning of ventral structures of the central nervous system. Fifteen different ndr2 alleles have been reported in zebrafish, of which eight were generated using chemical mutagenesis, four were radiation-induced, and the remaining alleles were obtained via random insertion, gene targeting (TALEN), or unknown methods. Therefore, most mutation sites were random and could not be predicted a priori. Using the CRISPR-Cas9 system from Streptococcus pyogenes, we targeted distinct regions in all three exons of zebrafish ndr2 and observed cyclopia in the injected (G0) embryos. We show that the use of sgRNA-Cas9 ribonucleoprotein (RNP) complexes can cause penetrant cyclopic phenotypes in injected (G0) embryos. Targeted PCR amplicon analysis using Sanger sequencing showed that most of the alleles had small indels resulting in frameshifts. The sequence information correlates with the loss of ndr2 activity. In this study, we validate multiple CRISPR targets using an in vitro nuclease assay and in vivo analysis using embryos. We describe one specific mutant allele resulting in loss of conserved terminal cysteine-coding sequences. This study is another demonstration of the utility of the CRISPR-Cas9 system in generating domain- specific mutations and provides further insights into the structure-function of the ndr2 gene.

A Preliminary Investigation of the Efficacy of Disgust Exposure Techniques in a Subclinical Population With Blood and Injection Fears

2008 ◽  
Vol 25 (3) ◽  
pp. 129-148 ◽  
Author(s):  
Michiyo Hirai ◽  
Heather M. Cochran ◽  
Jennifer S. Meyer ◽  
Jennifer L. Butcher ◽  
Laura L. Vernon ◽  
...  
Keyword(s):  
Preliminary Investigation ◽  
Effect Sizes ◽  
Single Session ◽  
Treatment Groups ◽  
Domain Specific ◽  
Injection Injury ◽  
Blood Injection ◽  
Bii Phobia ◽  
Over Time

AbstractThe current study examined whether a traditional exposure-based treatment for blood-injection-injury (BII) phobia would be effective at reducing disgust responses to BII stimuli and whether the addition of modules targeting disgust would provide incremental efficacy. Participants, many of whom reported subclinical BII phobia symptoms, underwent one of two single-session exposure protocols, one targeting fear alone, and the other targeting both fear and disgust. Both treatments consisted of education components (fear-only or fear-disgust) and in vivo exposure (fear-only or fear-disgust). Both the fear-only and the fear-disgust treatment groups significantly decreased fear and avoidance behaviour toward BII stimuli over time. The two groups also experienced similar reductions in disgust responses to BII-related stimuli and global as well as domain-specific disgust sensitivity. The effect sizes indicated that the fear-disgust group evidenced greater reduction in symptoms than did the fear-only group. The implications of the results for models of phobia maintenance and treatment are discussed.

scholarly journals Restoration of RPGR expression in vivo using CRISPR/Cas9 gene editing

Gene Therapy ◽  
2021 ◽  
Author(s):  
Jessica D. Gumerson ◽  
Amal Alsufyani ◽  
Wenhan Yu ◽  
Jingqi Lei ◽  
Xun Sun ◽  
...  
Keyword(s):  
Expression Vectors ◽  
End Joining ◽  
Reading Frame ◽  
Guide Rna ◽  
Domain Specific ◽  
Somatic Gene ◽  
Non Homologous End Joining ◽  
Cone Opsins ◽  
Inherited Retinal Degeneration

AbstractMutations in the gene for Retinitis Pigmentosa GTPase Regulator (RPGR) cause the X-linked form of inherited retinal degeneration, and the majority are frameshift mutations in a highly repetitive, purine-rich region of RPGR known as the OFR15 exon. Truncation of the reading frame in this terminal exon ablates the functionally important C-terminal domain. We hypothesized that targeted excision in ORF15 by CRISPR/Cas9 and the ensuing repair by non-homologous end joining could restore RPGR reading frame in a portion of mutant photoreceptors thereby correcting gene function in vivo. We tested this hypothesis in the rd9 mouse, a naturally occurring mutant line that carries a frameshift mutation in RPGRORF15, through a combination of germline and somatic gene therapy approaches. In germline gene-edited rd9 mice, probing with RPGR domain-specific antibodies demonstrated expression of full length RPGRORF15 protein. Hallmark features of RPGR mutation-associated early disease phenotypes, such as mislocalization of cone opsins, were no longer present. Subretinal injections of the same guide RNA (sgRNA) carried in AAV sgRNA and SpCas9 expression vectors restored reading frame of RPGRORF15 in a subpopulation of cells with broad distribution throughout the retina, confirming successful correction of the mutation. These data suggest that a simplified form of genome editing mediated by CRISPR, as described here, could be further developed to repair RPGRORF15 mutations in vivo.

scholarly journals All four putative ligand-binding domains in megalin contain pathogenic epitopes capable of inducing passive Heymann nephritis.

1998 ◽  
Vol 9 (9) ◽  
pp. 1638-1644
Author(s):  
H Yamazaki ◽  
R Ullrich ◽  
M Exner ◽  
A Saito ◽  
R A Orlando ◽  
...  
Keyword(s):  
Ligand Binding ◽  
Rat Kidney ◽  
Target Antigen ◽  
Specific Antibodies ◽  
Domain Specific ◽  
Binding Domains ◽  
Heymann Nephritis ◽  
Extracellular Region ◽  
Putative Ligand Binding

Megalin (gp330) is the main target antigen involved in the induction of Heymann nephritis (HN), a rat model of human membranous nephropathy. Its large extracellular region contains four putative ligand-binding domains separated by spacer regions. Previously, it was reported that the second ligand-binding domain (LBD II) of megalin is involved in the pathogenesis of passive HN because it is capable of binding antibodies in vivo and initiating formation of immune deposits (ID). This study explores the possibility that pathogenic epitopes might also be present in the other putative ligand-binding domains. Recombinant fragments of ligand-binding domains (LBD) I through IV expressed in a baculovirus system were used to generate polyclonal domain-specific antibodies. Antibodies raised against each of the recombinant megalin fragments reacted preferentially with its respective antigen and with whole megalin by immunoblotting. Each of the antibodies also gave a characteristic brush-border staining for megalin by indirect immunofluorescence on rat kidney. When rats were injected with the domain-specific antibodies to test their ability to produce passive HN, glomerular ID were present in kidneys of all injected animals. The staining pattern in glomeruli of rats injected with LBD I, III, or IV was similar to that obtained with antibodies to LBD II. It is concluded that passive HN can be induced with antibodies against LBD I, III, and IV, as well as LBD II, and that each of the ligand-binding domains contains a pathogenic epitope. These findings provide further evidence for the multiple epitope model of HN.

Abstract 278: Domain-specific Roles for GRK2 in Cardiac Hypertrophy and Heart Failure

2016 ◽  
Vol 119 (suppl_1) ◽  
Author(s):  
Sarah M Schumacher ◽  
Erhe Gao ◽  
J. Kurt Chuprun ◽  
Walter J. Koch
Keyword(s):  
Heart Failure ◽  
Interstitial Fibrosis ◽  
Heart Function ◽  
Pressure Overload ◽  
Left Ventricular ◽  
Cross Sectional ◽  
Amino Terminal ◽  
Domain Specific ◽  
Rgs Domain

During heart failure (HF), cardiac levels and activity of the G protein-coupled receptor (GPCR) kinase (GRK) GRK2 are elevated and contribute to adverse remodeling and contractile dysfunction, while inhibition via a carboxyl-terminal peptide, βARKct, enhances heart function and can prevent HF. Mounting evidence supports the idea of a dynamic “interactome” in which GRK2 can uncouple GPCRs via novel protein-protein interactions. Several GRK2 interacting partners are important for adaptive and maladaptive myocyte growth; therefore, an understanding of domain-specific interactions with signaling and regulatory molecules could lead to novel targets for HF therapy. For instance, GRK2 contains a putative amino-terminal R egulator of G protein S ignaling (RGS) domain (βARKrgs) that directly interacts with Gαq and inhibits signaling. Previously, our lab investigated cardiac-specific transgenic expression of a fragment of this RGS domain (βARKnt), that did not reduce acute hypertrophy after pressure overload or demonstrate RGS activity in vivo against Gαq-mediated signaling. In contrast, βARKnt induced hypertrophy and elevated β-adrenergic receptor (βAR) density without altering agonist-induced contractility or adenylyl cyclase activity, due to a compensatory increase in GRK2 activity. Importantly, βAR downregulation in response to chronic agonist administration was attenuated by βARKnt expression, indicating a novel regulation of βAR receptor density. Herein, we investigated the effect of βARKnt expression during chronic pressure overload post trans-aortic constriction (TAC). Echocardiographic analysis revealed increased posterior wall thickness and left-ventricular mass 4 weeks post-TAC compared to non-transgenic littermate controls. Importantly, despite enhanced hypertrophy, the progression to HF was inhibited in βARKnt mice 14 weeks post-TAC. Histological analysis of interstitial fibrosis and cross-sectional area is underway to determine alterations in maladaptive remodeling. Further, cardiomyocyte signaling and βARKnt protein-binding partners are a focus, since our data indicate that βARKnt-mediated regulation of βAR density may provide a novel means of cardioprotection during pressure-overload induced HF.

scholarly journals Whole-neuron synaptic mapping reveals local balance between excitatory and inhibitory synapse organization

2018 ◽  
Author(s):  
Daniel Maxim Iascone ◽  
Yujie Li ◽  
Uygar Sümbül ◽  
Michael Doron ◽  
Hanbo Chen ◽  
...  
Keyword(s):  
Spatial Organization ◽  
Pyramidal Neurons ◽  
Neural Circuits ◽  
Dendritic Tree ◽  
Neuronal Firing ◽  
Source Reconstruction ◽  
Domain Specific ◽  
Absolute Density ◽  
Cortical Pyramidal Neurons

SUMMARYThe balance between excitatory and inhibitory (E and I) synaptic inputs is thought to be critical for information processing in neural circuits. However, little is known about the principles of spatial organization of E and I synapses across the entire dendritic tree of mammalian neurons. We developed a new, open-source, reconstruction platform for mapping the size and spatial distribution of E and I synapses received by individual, genetically-labeled, layer 2/3 cortical pyramidal neurons (PNs) in vivo. We mapped over 90,000 E and I synapses across twelve L2/3 PNs and uncovered structured organization of E and I synapses across dendritic domains as well as within individual dendritic segments in these cells. Despite significant, domain-specific, variations in the absolute density of E and I synapses, their ratio is strikingly balanced locally across dendritic segments. Computational modeling indicates that this spatially-precise E/I balance dampens dendritic voltage fluctuations and strongly impacts neuronal firing output.

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