Merck
  • Home
  • Search Results
  • The Chlamydia pneumoniae Inclusion Membrane Protein Cpn1027 Interacts with Host Cell Wnt Signaling Pathway Regulator Cytoplasmic Activation/Proliferation-Associated Protein 2 (Caprin2).

The Chlamydia pneumoniae Inclusion Membrane Protein Cpn1027 Interacts with Host Cell Wnt Signaling Pathway Regulator Cytoplasmic Activation/Proliferation-Associated Protein 2 (Caprin2).

PloS one (2015-05-23)
Rhonda Flores, Guangming Zhong
ABSTRACT

We previously identified hypothetical protein Cpn1027 as a novel inclusion membrane protein that is unique to Chlamydia pneumoniae. In the current study, using a yeast-two hybrid screen assay, we identified host cell cytoplasmic activation/proliferation-associated protein 2 (Caprin2) as an interacting partner of Cpn1027. The interaction was confirmed and mapped to the C-termini of both Cpn1027 and Caprin2 using co-immunoprecipitation and GST pull-down assays. A RFP-Caprin2 fusion protein was recruited to the chlamydial inclusion and so was the endogenous GSK3β, a critical component of the β-catenin destruction complex in the Wnt signaling pathway. Cpn1027 also co-precipitated GSK3β. Caprin2 is a key regulator of the Wnt signaling pathway by promoting the recruitment of the β-catenin destruction complex to the cytoplasmic membrane in the presence of Wnt signaling while GSK3β is required for priming β-catenin for degradation in the absence of Wnt signaling. The Cpn1027 interactions with Caprin2 and GSK3β may allow C. pneumoniae to actively sequester the β-catenin destruction complex so that β-catenin is maintained even in the absence of extracellular Wnt activation signals. The maintained β-catenin can trans-activate Wnt target genes including Bcl-2, which may contribute to the chlamydial antiapoptotic activity. We found that the C. pneumoniae-infected cells were more resistant to apoptosis induction and the anti-apoptotic activity was dependent on β-catenin. Thus, the current study suggests that the chlamydial inclusion protein Cpn1027 may be able to manipulate host Wnt signaling pathway for enhancing the chlamydial anti-apoptotic activity.

MATERIALS
Product Number
Brand
Product Description

Sigma-Aldrich
DAPI, for nucleic acid staining
Sigma-Aldrich
Triton X-100, laboratory grade
Sigma-Aldrich
2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt, ≥98% (HPLC)
Sigma-Aldrich
2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt, tablet, 10 mg substrate per tablet
Sigma-Aldrich
2,2′-Azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) diammonium salt, ≥98% (HPLC)
Sigma-Aldrich
L-Glutathione reduced, BioXtra, ≥98.0%
Sigma-Aldrich
L-Glutathione reduced, suitable for cell culture, BioReagent, ≥98.0%, powder
Sigma-Aldrich
IPTG, ≥99% (TLC), ≤0.1% Dioxane
Sigma-Aldrich
Isopropyl β-D-1-thiogalactopyranoside, ≥99% (TLC)
Sigma-Aldrich
L-Glutathione reduced, ≥98.0%
SAFC
Isopropyl β-D-1-thiogalactopyranoside
Sigma-Aldrich
Isopropyl β-D-thiogalactopyranoside solution, ReadyMade IPTG solution for Blue-white screening
Sigma-Aldrich
Phenylmethanesulfonyl fluoride, ≥98.5% (GC)
Sigma-Aldrich
Phenylmethanesulfonyl fluoride, ≥99.0% (T)