Dataset Information

Novel Role of TRPML2 in the Regulation of the Innate Immune Response.

ABSTRACT: TRPMLs (or mucolipins) constitute a family of endosomal cation channels with homology to the transient receptor potential superfamily. In mammals, the TRPML family includes three members: TRPML1-3. Although TRPML1 and TRPML3 have been well characterized, the cellular function of TRPML2 has remained elusive. To address TRPML2 function in a physiologically relevant cell type, we first analyzed TRPML2 expression in different mouse tissues and organs and found that it was predominantly expressed in lymphoid organs and kidney. Quantitative RT-PCR revealed tight regulation of TRPML2 at the transcriptional level. Although TRPML2 expression was negligible in resting macrophages, TRPML2 mRNA and protein levels dramatically increased in response to TLR activation both in vitro and in vivo. Conversely, TRPML1 and TRPML3 levels did not change upon TLR activation. Immunofluorescence analysis demonstrated that endogenous TRPML2 primarily localized to recycling endosomes both in culture and primary cells, in contrast with TRPML1 and TRPML3, which distribute to the late and early endosomal pathway, respectively. To better understand the in vivo function of TRPML2, we generated a TRPML2-knockout mouse. We found that the production of several chemokines, in particular CCL2, was severely reduced in TRPML2-knockout mice. Furthermore, TRPML2-knockout mice displayed impaired recruitment of peripheral macrophages in response to i.p. injections of LPS or live bacteria, suggesting a potential defect in the immune response. Overall, our study reveals interesting differences in the regulation and distribution of the members of the TRPML family and identifies a novel role for TRPML2 in the innate immune response.

SUBMITTER: Sun L

PROVIDER: S-EPMC4637233 | biostudies-other | 2015 Nov

REPOSITORIES: biostudies-other

ACCESS DATA

Publications

Novel Role of TRPML2 in the Regulation of the Innate Immune Response.

Sun Lu L Hua Yinan Y Vergarajauregui Silvia S Diab Heba I HI Puertollano Rosa R

Journal of immunology (Baltimore, Md. : 1950) 20151002 10

TRPMLs (or mucolipins) constitute a family of endosomal cation channels with homology to the transient receptor potential superfamily. In mammals, the TRPML family includes three members: TRPML1-3. Although TRPML1 and TRPML3 have been well characterized, the cellular function of TRPML2 has remained elusive. To address TRPML2 function in a physiologically relevant cell type, we first analyzed TRPML2 expression in different mouse tissues and organs and found that it was predominantly expressed in ...[more]

PMID: 26432893

Similar Datasets

Project description:Background: We have hypothesized that different factors are involved in the severity of ACD and AD because some but not all patients with atopic dermatitis (AD) present with allergic conjunctival disease (ACD) including severe types such as atopic keratoconjunctivitis (AKC) with/without giant papillae. We previously reported that plasma miR-628-3p was up-regulated in AD with severe ACD, but not in severe AD without severe ACD or in our healthy controls. In this study, to investigate the pathogenesis of AD with and without severe ACD, we performed comprehensive plasma miRNA analysis and studied the function of some miRNAs which were significantly up-regulated in ACD. Methods: Transcriptomics analysis of miRNA was performed using the microarray platform from the plasma of nine individuals (AD, severe ACD, controls: n = 3 each). To confirm up-regulation of the 12 miRNAs of the eight miRNA groups we focused on, we performed quantitative miRNA polymerase chain reaction (PCR) assays using 80 plasma samples (AD: 23, severe ACD: 17, controls: 40). To study the function of the eight miRNAs which were significantly up-regulated in ACD, we transfected their mimic to THP-1 cells, a monocyte cell line, and performed comprehensive gene expression analysis of them. The up-regulation of gene expression of interest in transfected THP-1 cells with the hsa-let-7a-5p miRNA mimic was confirmed by quantitative RT-qPCR assay. Results: Quantitative miRNA PCR assays showed that hsa-let-7a-5p, hsa-let-7days-3p, hsa-let-7e-5p, and hsa-miR-151a-5p were significantly up-regulated in both AD-ACD + and AD-ACD - as were hsa-miR-130a-3p, hsa-miR-151a-3p, has-miR-27b-3p, and hsa-miR-146a-5p in AD-ACD + but not in AD-ACD - . The functions of each miRNA were investigated by comprehensive gene expression analysis of THP-1 cells transfected with each miRNA mimic. Of the eight miRNAs, hsa-let-7a-5p, hsa-let-7e-5p, has-miR-27b-3p, and hsa-miR-146a-5p mimic-transfected THP-1 cells showed the up-regulation of CXCL10 (IP-10; interferon gamma-induced protein 10), which might be one of the innate immune-related genes. Quantitative RT-qPCR assays of transfected THP-1 cells with the hsa-let-7a-5p miRNA mimic showed that the 17 genes up-regulated more than 10-fold in the comprehensive gene expression analysis, and TLR3, RIG-I, and MDA5, important innate immune-related genes, were significantly up-regulated. TNFSF13B, AIM2, USP41, STAP1, GBP4, CCL8, and IFI27, reportedly down-regulated by the hsa-miR-628-3p mimic, were also significantly up-regulated in the transfected cells. Conclusion: Hsa-let-7a-5p, which was significantly up-regulated in AD-ACD + and AD-ACD - , could positively regulate the important innate immune-related genes such as TLR3, RIG-I, and MDA5. It is possible that in an allergic disease such as atopic keratoconjunctivitis and/or dermatitis, innate immune responses might be positively regulated by hsa-let-7a-5p in the plasma.

Dataset Information

Novel Role of TRPML2 in the Regulation of the Innate Immune Response.

Publications

Novel Role of TRPML2 in the Regulation of the Innate Immune Response.

Similar Datasets

OmicsDI is part of the ELIXIR infrastructure

Tweets