Mapping Structural Determinants within Third Intracellular Loop That Direct Signaling Specificity of Type 1 Corticotropin-releasing Hormone Receptor

Punn, Anu; Chen, Jing; Delidaki, Maria; Tang, Jinjin; Liapakis, George; Lehnert, Hendrik; Levine, Michael A.; Grammatopoulos, Dimitris K.

doi:10.1074/jbc.m111.272161

Cited by 15 publications

(14 citation statements)

References 44 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Residues 5.61 and 5.65 contact the transducin C-terminal peptide in the opsin structures [32], but a larger range of residues contact the G-protein in the β 2 -AR 3SN6 structure. Mutations, particularly to polar amino acids, at position 5.61 and 5.65 in class A [33–36] and class B [37–39] GPCRs inhibit G-protein coupling. It is important to consider the G-protein interaction when seeking to understand the mutagenesis results for residues at the intracellular end of TM5 Here, the 3SN6 β 2 -AR–G-protein complex is a reasonable model since both CLR and the β 2 -AR couple to Gs.…”

Section: Resultsmentioning

confidence: 99%

“…The KxxK 6.35 motif may interact with the C-terminus of Gαs, aided by flexing of TM6 around P 6.42 (class B) or P 6.50 (class A). This interaction is born out by MD simulations, but the analogous residues in the β 2 -AR–Gs complex (PDB code 3SN6) are poorly resolved and so the interpretation should be used with care, despite the observations from mutagenesis experiments that implicate K 6.32 and K 6.35 in G-protein coupling in both class A [36,46–48] and class B [39,49–52] GPCRs. For this reason, it is important to note that the alignment is based on mutagenesis results throughout the transmembrane region and not in just one region, such as the G-protein coupling region.…”

Section: Resultsmentioning

confidence: 99%

See 1 more Smart Citation

Similarity between class A and class B G-protein-coupled receptors exemplified through calcitonin gene-related peptide receptor modelling and mutagenesis studies

Vohra

Taddese

Conner

et al. 2013

J. R. Soc. Interface.

View full text Add to dashboard Cite

Modelling class B G-protein-coupled receptors (GPCRs) using class A GPCR structural templates is difficult due to lack of homology. The plant GPCR, GCR1, has homology to both class A and class B GPCRs. We have used this to generate a class A–class B alignment, and by incorporating maximum lagged correlation of entropy and hydrophobicity into a consensus score, we have been able to align receptor transmembrane regions. We have applied this analysis to generate active and inactive homology models of the class B calcitonin gene-related peptide (CGRP) receptor, and have supported it with site-directed mutagenesis data using 122 CGRP receptor residues and 144 published mutagenesis results on other class B GPCRs. The variation of sequence variability with structure, the analysis of polarity violations, the alignment of group-conserved residues and the mutagenesis results at 27 key positions were particularly informative in distinguishing between the proposed and plausible alternative alignments. Furthermore, we have been able to associate the key molecular features of the class B GPCR signalling machinery with their class A counterparts for the first time. These include the [K/R]KLH motif in intracellular loop 1, [I/L]xxxL and KxxK at the intracellular end of TM5 and TM6, the NPXXY/VAVLY motif on TM7 and small group-conserved residues in TM1, TM2, TM3 and TM7. The equivalent of the class A DRY motif is proposed to involve Arg2.39, His2.43 and Glu3.46, which makes a polar lock with T6.37. These alignments and models provide useful tools for understanding class B GPCR function.

show abstract

Section: Resultsmentioning

confidence: 99%

Section: Resultsmentioning

confidence: 99%

Similarity between class A and class B G-protein-coupled receptors exemplified through calcitonin gene-related peptide receptor modelling and mutagenesis studies

Vohra

Taddese

Conner

et al. 2013

J. R. Soc. Interface.

View full text Add to dashboard Cite

show abstract

“…CRF 1 and CRF 2 receptors are class B1 (secretin-like) GPCRs with complex signaling mechanisms that can couple to different G proteins in a cell-type-specific manner to produce an array of downstream signaling. Although both receptors are reported to activate Gas and cAMP signaling and Gq and Ca 2+ signaling [56,57], there is also clear evidence for coupling to Gq/11 and Gi/o proteins [30,[58][59][60]. The latter 2 contribute to activating ERK [58,61].…”

Section: Discussionmentioning

confidence: 99%

Frontline Science: Corticotropin-releasing factor receptor subtype 1 is a critical modulator of mast cell degranulation and stress-induced pathophysiology

Ayyadurai

Gibson²,

D’Costa

et al. 2017

Journal of Leukocyte Biology

View full text Add to dashboard Cite

Life stress is a major risk factor in the onset and exacerbation of mast cell-associated diseases, including allergy/anaphylaxis, asthma, and irritable bowel syndrome. Although it is known that mast cells are highly activated upon stressful events, the mechanisms by which stress modulates mast cell function and disease pathophysiology remains poorly understood. Here, we investigated the role of corticotropin-releasing factor receptor subtype 1 (CRF) in mast cell degranulation and associated disease pathophysiology. In a mast cell-dependent model of IgE-mediated passive systemic anaphylaxis (PSA), prophylactic administration of the CRF-antagonist antalarmin attenuated mast cell degranulation and hypothermia. Mast cell-deficient mice engrafted with CRF bone marrow-derived mast cells (BMMCs) exhibited attenuated PSA-induced serum histamine, hypothermia, and clinical scores compared with wild-type BMMC-engrafted mice. mice engrafted with CRF BMMCs also exhibited suppressed in vivo mast cell degranulation and intestinal permeability in response to acute restraint stress. Genetic and pharmacologic experiments with murine BMMCs, rat RBL-2H3, and human LAD2 mast cells demonstrated that although CRF activation did not directly induce MC degranulation, CRF signaling potentiated the degranulation responses triggered by diverse mast cell stimuli and was associated with enhanced release of Ca from intracellular stores. Taken together, our results revealed a prominent role for CRF signaling in mast cells as a positive modulator of stimuli-induced degranulation and in vivo pathophysiologic responses to immunologic and psychologic stress.

show abstract

“…In 1988, using flash photolysis, Franke et al (59) demonstrated that a mutation of K248 in IL3 of rhodopsin did not affect G‐protein (transducin) binding but impaired G‐protein activation. Since this early report, other studies have shown the importance of IL3 in G‐protein binding and activation, including a recent report on the corticotropin‐releasing hormone receptor that showed the importance of several arginine and lysine residues in this domain in the activation of G‐proteinmediated signaling cascades (60). Although an increasing number of studies have implicated arginine residues in ILs as important for GPCR signaling, no consensus sequence for G‐protein coupling has been identified, likely due to the high sequence diversity within these loops among GPCRs.…”

Section: Discussionmentioning

confidence: 99%

TACR3mutations disrupt NK3R function through distinct mechanisms in GnRH‐deficient patients

Noel

Abreu

et al. 2013

FASEB j.

View full text Add to dashboard Cite

Neurokinin B (NKB) and its G-protein-coupled receptor, NK3R, have been implicated in the neuroendocrine control of GnRH release; however, little is known about the structure-function relationship of this ligand-receptor pair. Moreover, loss-of-function NK3R mutations cause GnRH deficiency in humans. Using missense mutations in NK3R we previously identified in patients with GnRH deficiency, we demonstrate that Y256H and Y315C NK3R mutations in the fifth and sixth transmembrane domains (TM5 and TM6), resulted in reduced whole-cell (79.3±7.2%) or plasma membrane (67.3±7.3%) levels, respectively, compared with wild-type (WT) NK3R, with near complete loss of inositol phosphate (IP) signaling, implicating these domains in receptor trafficking, processing, and/or stability. We further demonstrate in a FRET-based assay that R295S NK3R, in the third intracellular loop (IL3), bound NKB but impaired dissociation of Gq-protein subunits from the receptor compared with WT NK3R, which showed a 10.0 ± 1.3% reduction in FRET ratios following ligand binding, indicating activation of Gq-protein signaling. Interestingly, R295S NK3R, identified in the heterozygous state in a GnRH-deficient patient, also interfered with dissociation of G proteins and IP signaling from wild-type NK3R, indicative of dominant-negative effects. Collectively, our data illustrate roles for TM5 and TM6 in NK3R trafficking and ligand binding and for IL3 in NK3R signaling.

show abstract

Mapping Structural Determinants within Third Intracellular Loop That Direct Signaling Specificity of Type 1 Corticotropin-releasing Hormone Receptor

Cited by 15 publications

References 44 publications

Similarity between class A and class B G-protein-coupled receptors exemplified through calcitonin gene-related peptide receptor modelling and mutagenesis studies

Similarity between class A and class B G-protein-coupled receptors exemplified through calcitonin gene-related peptide receptor modelling and mutagenesis studies

Frontline Science: Corticotropin-releasing factor receptor subtype 1 is a critical modulator of mast cell degranulation and stress-induced pathophysiology

TACR3mutations disrupt NK3R function through distinct mechanisms in GnRH‐deficient patients

Contact Info

Product

Resources

About