Reduced GRK2 level in T cells potentiates chemotaxis and signaling in response to CCL4

Vroon, Anne; Heijnen, Cobi J.; Lombardi, Maria Stella; Cobelens, Pieter M.; Mayor, Federico; Caron, Marc G.; Kavelaars, Annemieke

doi:10.1189/jlb.0403136

Cited by 95 publications

(75 citation statements)

References 37 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…In splenocytes from GRK2 hemizygous mice, an enhanced ERK activation is observed in response to chemokines. These findings are in excellent agreement with recent results (Vroon et al, 2004) showing that in T-cells, reduced GRK2 expression is also associated with increased phosphorylation of protein kinase B and MAPK activation by CCL4 and to increased migration toward chemokines. This effect can have interesting physiological consequences.…”

Section: Regulation Of Erk Activation By Grk2supporting

confidence: 83%

G Protein-coupled Receptor Kinase 2 Negatively Regulates Chemokine Signaling at a Level Downstream from G Protein Subunits

Jiménez-Sainz

Murga²,

Kavelaars³

et al. 2006

MBoC

Self Cite

View full text Add to dashboard Cite

The G protein-coupled receptor kinase 2 (GRK2) phosphorylates and desensitizes ligand-activated G protein-coupledreceptors. Here, evidence is shown for a novel role of GRK2 in regulating chemokine-mediated signals. The presence of increased levels of GRK2 in human embryonic kidney (HEK) 293 cells produced a significant reduction of the extracellular signal-regulated kinase (ERK) response to CCL2. This effect is independent of its role in receptor phosphorylation because the kinase-deficient mutant GRK2K220R was able to reduce this response, and ERK activation by CCR2BIX, a phosphorylation-defective receptor mutant, was also inhibited by GRK2. Constructs containing the G␣ q -binding RGS-like RH domain of GRK2 or its G␤␥-binding domain could not reproduce the inhibition, thus revealing that GRK2 acts downstream of G proteins. Interestingly, chemokine-driven mitogen-activated protein kinase kinase (MEK) stimulation is not affected in cells overexpressing GRK2 or GRK2K220R or in splenocytes from heterozygous GRK2 mice, where reduced kinase levels correlate with enhanced ERK activation by chemokines. We find GRK2 and MEK in the same multimolecular complex, thus suggesting a mechanism for GRK2 regulation of ERK activity that involves a direct or coordinate interaction with MEK. These results suggest an important role for GRK2 in the control of chemokine induction of ERK activation at the level of the MEK-ERK interface. INTRODUCTIONG protein-coupled receptor kinases (GRKs) are serine/threonine protein kinases that control the desensitization process of the G protein-coupled receptor family (Penela et al., 2003;Willets et al., 2003). GRK2 in particular is one of the best characterized GRK isoforms and has been shown to phosphorylate and desensitize the agonist-bound form of many G protein-coupled receptors (GPCRs) (Aragay et al., 1998b). Receptor phosphorylation is followed by high-affinity binding of arrestins to the receptor, which sterically inhibits further G protein activation. Although it is now clear that arrestins serve additional roles as multifunctional adaptor molecules, emerging new evidence also unveils unexpected roles for GRKs, including the phosphorylation of nonreceptor substrates, of non-GPCR receptors, and the association to different proteins such as phosphoinositide 3-kinase, GIT, or clathrin (Penela et al., 2003;Willets et al., 2003). Moreover, the GRK2/3 subfamily members contain a Cterminal G␤␥-binding region (Carman et al., 2000;Willets et al., 2003) and are able to inactivate G protein-dependent pathways in a phosphorylation-independent manner involving their avid interaction with G␣ q family members via their RGS-like RH N-terminal domain (Carman et al., 1999;Sallese et al., 2000).Chemokines bind to a variety of GPCRs, thus mediating chemotactic and proadhesion effects in leukocytes and other cell types (Rossi and Zlotnik, 2000). The CC chemokine receptor, CCR2, exclusively binds CCL2 produced by endothelial cells, smooth muscle cells, and macrophages in response to a variety of mediators. Dis...

show abstract

Section: Regulation Of Erk Activation By Grk2supporting

confidence: 83%

G Protein-coupled Receptor Kinase 2 Negatively Regulates Chemokine Signaling at a Level Downstream from G Protein Subunits

Jiménez-Sainz

Murga²,

Kavelaars³

et al. 2006

MBoC

Self Cite

View full text Add to dashboard Cite

show abstract

“…The chemokine CCL3 acts via GPCRs regulated by GRK2 Vroon et al, 2004). However, CCL3 receptors do not signal to cAMP but to an IP 3 /calcium-dependent pathway.…”

Section: Discussionmentioning

confidence: 99%

Low Nociceptor GRK2 Prolongs Prostaglandin E₂Hyperalgesia via Biased cAMP Signaling to Epac/Rap1, Protein Kinase Cε, and MEK/ERK

et al. 2010

View full text Add to dashboard Cite

Hyperexcitability of peripheral nociceptive pathways is often associated with inflammation and is an important mechanism underlying inflammatory pain. Here we describe a completely novel mechanism via which nociceptor G-protein-coupled receptor kinase 2 (GRK2) contributes to regulation of inflammatory hyperalgesia. We show that nociceptor GRK2 is downregulated during inflammation. In addition, we show for the first time that prostaglandin E 2 (PGE 2 )-induced hyperalgesia is prolonged from Ͻ6 h in wild-type (WT) mice to 3 d in mice with low GRK2 in Na v 1.8 ϩ nociceptors (SNS-GRK2 ϩ/Ϫ mice). This prolongation of PGE 2 hyperalgesia in SNS-GRK2 ϩ/Ϫ mice does not depend on changes in the sensitivity of the prostaglandin receptors because prolonged hyperalgesia also developed in response to 8-Br-cAMP. PGE 2 or cAMP-induced hyperalgesia in WT mice is PKA dependent. However, PKA activity is not required for hyperalgesia in SNS-GRK2 ϩ/Ϫ mice. SNS-GRK2 ϩ/Ϫ mice developed prolonged hyperalgesia in response to the Exchange proteins directly activated by cAMP (Epac) activator 8-pCPT-2Ј-O-Me-cAMP (8-pCPT). Coimmunoprecipitation experiments showed that GRK2 binds to Epac1. In vitro, GRK2 deficiency increased 8-pCPT-induced activation of the downstream effector of Epac, Rap1, and extracellular signal-regulated kinase (ERK). In vivo, inhibition of MEK1 or PKC prevented prolonged PGE 2 , 8-Br-cAMP, and 8-pCPT hyperalgesia in SNS-GRK2 ϩ/Ϫ mice. In conclusion, we discovered GRK2 as a novel Epac1-interacting protein. A reduction in the cellular level of GRK2 enhances activation of the Epac-Rap1 pathway. In vivo, low nociceptor GRK2 leads to prolonged inflammatory hyperalgesia via biased cAMP signaling from PKA to Epac-Rap1, ERK/PKC pathways.

show abstract

“…In addition to identifying a number of previously annotated secondary structures such as miRNA stem loops (e.g., miR-296) and snoRNAs (e.g., snoRNA-HACA39/HACA60), our analysis also unearthed a number of high-confidence novel structures (supplemental Table S8). For example, the ncRNA (AK154685) is a noncoding isoform of Ccl4, a chemokine important in T cell adhesion and migration (90). Up-regulated in both memory and activated T cells, this ncRNA overlaps the entire Ccl4 premRNA and then extends ϳ750 bp downstream (Fig.…”

Section: Expressed Ncrnas Exhibit Evolutionary Conservation Of Primarmentioning

confidence: 99%

Genome-Wide Identification of Long Noncoding RNAs in CD8+ T Cells

Pang

Dinger²,

Mercer³

et al. 2009

The Journal of Immunology

212

191

View full text Add to dashboard Cite

Previous research into the molecular mechanisms that underlie Ag-specific CD8؉ T cell differentiation and function has largely focused on the role of proteins. However, it is now apparent that the mammalian genome expresses large numbers of long (>200 nt) nonprotein-coding RNAs (ncRNAs), and there is increasing evidence that these RNAs have important regulatory functions, particularly in the regulation of epigenetic processes underpinning cell differentiation. In this study, we show that CD8 ؉ T cells express hundreds of long ncRNAs, many of which are lymphoid-specific and/or change dynamically with lymphocyte differentiation or activation. Numerous ncRNAs surround or overlap immunologically important protein-coding genes and can be predicted to function via a range of regulatory mechanisms. The overlap of many long ncRNAs expressed in CD8 ؉ T cells with microRNAs and small interfering RNAs further suggests that long ncRNAs may be processed into and exert their effects via smaller functional species. Finally, we show that the majority of long ncRNAs expressed in CD8 ؉ T cells harbor signatures of evolutionary conservation, secondary structures, and/or regulated promoters, further supporting their functionality. Taken together, our findings represent the first systematic discovery of long ncRNAs expressed in CD8؉ T cells and suggest that many of these transcripts are likely to play a role in adaptive immunity. The Journal of Immunology, 2009, 182: 7738 -7748. C ytotoxic CD8ϩ T cells represent a critical arm of the adaptive immune system. They originate from common lymphoid precursors in the bone marrow and undergo subsequent selection in the thymus. Following viral infection, naive CD8 ϩ T cells develop into effector cells that, upon activation, kill infected host cells and limit viral spread. Once an infection is cleared, most CD8 ϩ T cells undergo programmed cell death, leaving behind a minority of self-renewable memory CD8 ϩ T cells that are able to rapidly mount a protective response upon subsequent viral challenge. Intensive study over the past few decades has considerably advanced our knowledge of the functional and phenotypic changes that occur throughout the CD8 ϩ T cell life cycle. Nevertheless, our knowledge of the underlying regulatory basis for CD8 ϩ T cell differentiation and function remains incomplete. In the past decade, it has become increasingly evident that nonprotein-coding RNAs (ncRNAs) 4 fulfill critical regulatory roles in mammalian biology. Most attention has focused on short RNAs, including small interfering RNAs (siRNAs), microRNAs (miRNAs), and PIWI-interacting RNAs, which regulate gene expression at the transcriptional and/or posttranscriptional levels (reviewed in Refs. 1 and 2). Although less prominent, long ncRNAs (Ͼ200nt) have also been recognized as serving important biological functions (reviewed in Ref.3). Air and HOTAIR, for instance, coordinate and regulate gene expression within the Igf2r and HOX loci, respectively, whereas Xist does so across an entire chromosome (4 -6). In ...

show abstract

Reduced GRK2 level in T cells potentiates chemotaxis and signaling in response to CCL4

Cited by 95 publications

References 37 publications

G Protein-coupled Receptor Kinase 2 Negatively Regulates Chemokine Signaling at a Level Downstream from G Protein Subunits

G Protein-coupled Receptor Kinase 2 Negatively Regulates Chemokine Signaling at a Level Downstream from G Protein Subunits

Low Nociceptor GRK2 Prolongs Prostaglandin E₂Hyperalgesia via Biased cAMP Signaling to Epac/Rap1, Protein Kinase Cε, and MEK/ERK

Genome-Wide Identification of Long Noncoding RNAs in CD8+ T Cells

Contact Info

Product

Resources

About

Reduced GRK2 level in T cells potentiates chemotaxis and signaling in response to CCL4

Cited by 95 publications

References 37 publications

G Protein-coupled Receptor Kinase 2 Negatively Regulates Chemokine Signaling at a Level Downstream from G Protein Subunits

G Protein-coupled Receptor Kinase 2 Negatively Regulates Chemokine Signaling at a Level Downstream from G Protein Subunits

Low Nociceptor GRK2 Prolongs Prostaglandin E2Hyperalgesia via Biased cAMP Signaling to Epac/Rap1, Protein Kinase Cε, and MEK/ERK

Genome-Wide Identification of Long Noncoding RNAs in CD8+ T Cells

Contact Info

Product

Resources

About

Low Nociceptor GRK2 Prolongs Prostaglandin E₂Hyperalgesia via Biased cAMP Signaling to Epac/Rap1, Protein Kinase Cε, and MEK/ERK