To analyze the autoantigenic epitopes of the Sm B polypeptide of the U1 small nuclear RNP (snRNP) using complementary DNA (cDNA) clones. Expression of Sm B fusion proteins in lambda phage vectors, immunoblots, immunoprecipitations, and affinity purification of antibodies. Immunoblots using antibodies affinity-purified from B fusion proteins demonstrated that there were cross-reactive epitopes between the B'/B and A polypeptides of the U1 snRNP. Immunoprecipitation assays suggested that there were at least 3 different autoantigenic epitopes on the B polypeptide that could be classified into 2 general groups based upon autoantibody reactivity. The first group of autoantibodies, which bound 2 separate autoantigenic epitopes (BU1-1, BU1-2), participated in immunoprecipitation of the U1 snRNP alone. The second group, which bound the third type of autoantigenic epitope (BSm-1), immunoprecipitated all the abundant Sm snRNPs. There is at least 1 region on the B proteins that is accessible to antibodies only within the structure of the U1 snRNP, as well as a region that is accessible on all Sm snRNPs. These data support the notion that the native U1 RNP, perhaps containing B proteins in a different conformation than those found on other...Continue Reading
Electrophoretic transfer of proteins from polyacrylamide gels to nitrocellulose sheets: procedure and some applications
Epitope patterns of anti-RNP antibodies in rheumatic diseases. Evidence for an antigen-driven autoimmune response
Evidence for three distinct D proteins, which react differentially with anti-Sm autoantibodies, in the cores of the major snRNPs U1, U2, U4/U6 and U5
A repeated proline-rich sequence in Sm B/B' and N is a dominant epitope recognized by human and murine autoantibodies
Immunization of mice with purified U1 small nuclear ribonucleoprotein (RNP) induces a pattern of antibody specificities characteristic of the anti-Sm and anti-RNP autoimmune response of patients with lupus erythematosus, as measured by monoclonal antibodies
Small nuclear RNA-associated proteins are immunologically related as revealed by mapping of autoimmune reactive B-cell epitopes.
Biochemical and immunological heterogeneity of the Ro ribonucleoprotein particles. Analysis with sera specific for the RohY5 particle.
Molecular cloning of cDNA encoding Sm autoantigen: derivation of a cDNA for a B polypeptide of the U series of small nuclear ribonucleoprotein particles
The U1 RNA-binding site of the U1 small nuclear ribonucleoprotein (snRNP)-associated A protein suggests a similarity with U2 snRNPs.
A specific 31-nucleotide domain of U1 RNA directly interacts with the 70K small nuclear ribonucleoprotein component.
The U2 small nuclear ribonucleoprotein particle as an autoantigen. Analysis with sera from patients with overlap syndromes.
Tissue-specific expression and cDNA cloning of small nuclear ribonucleoprotein-associated polypeptide N.
Human U1 snRNP-specific C protein: complete cDNA and protein sequence and identification of a multigene family in mammals.
Plant small nuclear RNAs. IV. The structure of U1 RNA from Chlorella saccharophila: a phylogenetic support, in terms of RNA structure, for the probable interaction between U1 and U2 and RNPs during the splicing of pre-mRNA
Distinctive immune response patterns of human and murine autoimmune sera to U1 small nuclear ribonucleoprotein C protein
A major, novel systemic lupus erythematosus autoantibody class recognizes the E, F, and G Sm snRNP proteins as an E-F-G complex but not in their denatured states
Lupus autoantibodies discriminate between the highly homologous Sm polypeptides B/B' and SmN by binding an epitope restricted to B/B'
No evidence of epitope spreading after immunization with the major Sm epitope P-P-G-M-R-P-P anchored to sequential oligopeptide carriers (SOCs)
Autoimmune diseases occur as a result of an attack by the immune system on the body’s own tissues resulting in damage and dysfunction. There are different types of autoimmune diseases, in which there is a complex and unknown interaction between genetics and the environment. Discover the latest research on autoimmune diseases here.