title: Immunoglobulin switch region-like sequences in Drosophila melanogaster.
abstract: We found immunoglobulin switch (S) region-like sequences in DNAs of wide variety of organisms including sea urchin, yeast and Drosophila that do not produce immunoglobulins. DNA fragments carrying Smu-like sequences were cloned from Drosophila and the nucleotide sequence of a clone is almost identical to that of the mouse Smu region. Restriction fragments of Drosophila Smu-like sequences and their flanking regions seem to vary among Drosophila species. Possible evolutionary significance of the Smu-like sequence in invertebrates was discussed.
mesh_terms: D000818:Animals; D001483:Base Sequence; D005075:Biological Evolution; D003001:Cloning, Molecular; D004262:DNA Restriction Enzymes; D004274:DNA, Recombinant; D004331:Drosophila melanogaster / Q000235:genetics / Q000276:immunology*; D005796:Genes; D007136:Immunoglobulins / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000235:genetics; D012617:Sea Urchins / Q000235:genetics; D013045:Species Specificity
chemical_list: D004274:DNA, Recombinant; D007136:Immunoglobulins; D004262:DNA Restriction Enzymes