Advanced

Globular C1q receptor (p33) binds and stabilizes pro-inflammatory MCP-1 : a novel mechanism for regulation of MCP-1 production and function

Anders, Emma LU ; Nebel, Daniel LU ; Westman, Johannes LU ; Herwald, Heiko LU ; Nilsson, Bengt Olof LU and Svensson, Daniel LU (2018) In Biochemical Journal 475(4). p.775-786
Abstract

The protein gC1qR (globular C1q receptor), also named p33, was originally identified as a binding partner of the globular heads of C1q in the complement system. gC1qR/p33 is abundantly expressed in many cell types, but the functional importance of this protein is not completely understood. Here, we investigate the impact of gC1qR/p33 on the production and function of the pathophysiologically important chemokine monocyte chemoattractant protein-1 (MCP-1) and the underlying molecular mechanisms. Knockdown of gC1qR/p33 negatively regulated the production of MCP-1, but had no effect on the expression of transcript for MCP-1 in human periodontal ligament cells, suggesting a translational/post-translational mechanism of action. Laser scanning... (More)

The protein gC1qR (globular C1q receptor), also named p33, was originally identified as a binding partner of the globular heads of C1q in the complement system. gC1qR/p33 is abundantly expressed in many cell types, but the functional importance of this protein is not completely understood. Here, we investigate the impact of gC1qR/p33 on the production and function of the pathophysiologically important chemokine monocyte chemoattractant protein-1 (MCP-1) and the underlying molecular mechanisms. Knockdown of gC1qR/p33 negatively regulated the production of MCP-1, but had no effect on the expression of transcript for MCP-1 in human periodontal ligament cells, suggesting a translational/post-translational mechanism of action. Laser scanning confocal microscopy showed considerable cytosolic co-localization of gC1qR/p33 and MCP-1, and co-immunoprecipitation disclosed direct physical interaction between gC1qR/p33 and MCP-1. Surface plasmon resonance analysis revealed a high-affinity binding (KD = 10.9 nM) between gC1qR/p33 and MCP-1. Using a transwell migration assay, we found that recombinant gC1qR/p33 enhances MCP-1-induced migration of human THP-1 monocytes, pointing to a functional importance of the interaction between gC1qR/p33 and MCP-1. An in vitro assay revealed a rapid turnover of the MCP-1 protein and that gC1qR/ p33 stabilizes MCP-1, hence preventing its degradation. We propose that endogenous gC1qR/p33 physically interacts with MCP-1 causing stabilization of the MCP-1 protein and stimulation of its activity in human periodontal ligament cells, suggesting a novel gC1qR/p33-mediated pro-inflammatory mechanism of action.

(Less)
Please use this url to cite or link to this publication:
author
organization
publishing date
type
Contribution to journal
publication status
published
subject
in
Biochemical Journal
volume
475
issue
4
pages
12 pages
publisher
Portland Press Limited
external identifiers
  • scopus:85046906814
  • pmid:29358188
ISSN
0264-6021
DOI
10.1042/BCJ20170857
language
English
LU publication?
yes
id
084ff24a-c79e-4542-817d-38670480c636
date added to LUP
2018-05-25 12:43:53
date last changed
2019-11-20 05:19:35
@article{084ff24a-c79e-4542-817d-38670480c636,
  abstract     = {<p>The protein gC1qR (globular C1q receptor), also named p33, was originally identified as a binding partner of the globular heads of C1q in the complement system. gC1qR/p33 is abundantly expressed in many cell types, but the functional importance of this protein is not completely understood. Here, we investigate the impact of gC1qR/p33 on the production and function of the pathophysiologically important chemokine monocyte chemoattractant protein-1 (MCP-1) and the underlying molecular mechanisms. Knockdown of gC1qR/p33 negatively regulated the production of MCP-1, but had no effect on the expression of transcript for MCP-1 in human periodontal ligament cells, suggesting a translational/post-translational mechanism of action. Laser scanning confocal microscopy showed considerable cytosolic co-localization of gC1qR/p33 and MCP-1, and co-immunoprecipitation disclosed direct physical interaction between gC1qR/p33 and MCP-1. Surface plasmon resonance analysis revealed a high-affinity binding (K<sub>D</sub> = 10.9 nM) between gC1qR/p33 and MCP-1. Using a transwell migration assay, we found that recombinant gC1qR/p33 enhances MCP-1-induced migration of human THP-1 monocytes, pointing to a functional importance of the interaction between gC1qR/p33 and MCP-1. An in vitro assay revealed a rapid turnover of the MCP-1 protein and that gC1qR/ p33 stabilizes MCP-1, hence preventing its degradation. We propose that endogenous gC1qR/p33 physically interacts with MCP-1 causing stabilization of the MCP-1 protein and stimulation of its activity in human periodontal ligament cells, suggesting a novel gC1qR/p33-mediated pro-inflammatory mechanism of action.</p>},
  author       = {Anders, Emma and Nebel, Daniel and Westman, Johannes and Herwald, Heiko and Nilsson, Bengt Olof and Svensson, Daniel},
  issn         = {0264-6021},
  language     = {eng},
  month        = {02},
  number       = {4},
  pages        = {775--786},
  publisher    = {Portland Press Limited},
  series       = {Biochemical Journal},
  title        = {Globular C1q receptor (p33) binds and stabilizes pro-inflammatory MCP-1 : a novel mechanism for regulation of MCP-1 production and function},
  url          = {http://dx.doi.org/10.1042/BCJ20170857},
  doi          = {10.1042/BCJ20170857},
  volume       = {475},
  year         = {2018},
}