Assembly of major histocompatibility complex (MHC) class I molecules in human cells is dependent on the accessory protein tapasin, which mediates their interaction with the transporters associated with antigen processing (TAP) and thereby ensures efficient peptide binding. Analysis of a mouse tapasin complementary DNA defined a conserved polypeptide sharing sequences diagnostic of a transmembrane protein related to the immunoglobulin superfamily, and an endoplasmic reticulum retention motif. The mouse tapasin gene was mapped about 70 kilobases from H2-K at the centromeric end of the mouse MHC. Expression of mouse tapasin in a tapasin-deficient human mutant cell line restored the normal assembly and expression of class I alleles. Thus, tapasin is a structurally and functionally conserved component of the MHC class I antigen processing pathway. Its genetic linkage to the class I and TAP subunit genes in the MHC may be of significance in the coordinate expression and functional coadaptation of the diverse gene products.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1007/s002510050430 | DOI Listing |
J Med Virol
April 2023
Department of Infectious Diseases, Shanghai Sixth People's Hospital Affiliated to Shanghai Jiao Tong University School of Medicine, Shanghai, China.
Hepatitis B virus (HBV) specific T cell immune response plays a vital role in viral clearance. Dendritic cell derived exosomes (Dexs) can activate T cell immunity effectively. Tapasin (TPN) is involved in antigen processing and specific immune recognition.
View Article and Find Full Text PDFFront Cell Infect Microbiol
March 2023
Department of Microbiology, Immunology and Molecular Genetics, University of Kentucky College of Medicine, Lexington, KY, United States.
We previously demonstrated that brain-resident cells produce IFN-γ in response to reactivation of cerebral infection with . To obtain an overall landscape view of the effects of IFN-γ from brain-resident cells on the cerebral protective immunity, in the present study we employed NanoString nCounter assay and quantified mRNA levels for 734 genes in myeloid immunity in the brains of T and B cell-deficient, bone marrow chimeric mice with and without IFN-γ production by brain-resident cells in response to reactivation of cerebral infection. Our study revealed that IFN-γ produced by brain-resident cells amplified mRNA expression for the molecules to activate the protective innate immunity including 1) chemokines for recruitment of microglia and macrophages (CCL8 and CXCL12) and 2) the molecules for activating those phagocytes (IL-18, TLRs, NOD1, and CD40) for killing tachyzoites.
View Article and Find Full Text PDFFront Immunol
December 2022
Tumor Immunotherapy and Microenvironment (TIME) group, Department of Cancer Research, Luxembourg Institute of Health (LIH), Luxembourg City, Luxembourg.
Harmine is a dual-specificity tyrosine-regulated kinase 1A (DYRK1A) inhibitor that displays a number of biological and pharmacological properties. Also referred to as ACB1801 molecule, we have previously reported that harmine increases the presentation of major histocompatibility complex (MHC)-I-dependent antigen on melanoma cells. Here, we show that ACB1801 upregulates the mRNA expression of several proteins of the MHC-I such as Transporter Associated with antigen Processing TAP1 and 2, Tapasin and Lmp2 (hereafter referred to as MHC-I signature) in melanoma cells.
View Article and Find Full Text PDFProc Natl Acad Sci U S A
October 2022
Department of Pathology, University of Massachusetts Chan Medical School, Worcester, MA 01655.
MHC molecules are not randomly distributed on the plasma membrane but instead are present in discrete nanoclusters. The mechanisms that control formation of MHC I nanoclusters and the importance of such structures are incompletely understood. Here, we report a molecular association between tetraspanin-5 (Tspan5) and MHC I molecules that started in the endoplasmic reticulum and was maintained on the plasma membrane.
View Article and Find Full Text PDFFront Immunol
August 2022
Institute for Immunology and Infection Research, University of Edinburgh, Edinburgh, United Kingdom.
The functions of a wide variety of molecules with structures similar to the classical class I and class II molecules encoded by the major histocompatibility complex (MHC) have been studied by biochemical and structural studies over decades, with many aspects for humans and mice now enshrined in textbooks as dogma. However, there is much variation of the MHC and MHC molecules among the other jawed vertebrates, understood in the most detail for the domestic chicken. Among the many unexpected features in chickens is the co-evolution between polymorphic TAP and tapasin genes with a dominantly-expressed class I gene based on a different genomic arrangement compared to typical mammals.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!