title: The DNA puff 4C expresses a salivary secretion protein in Trichosia pubescens (Diptera; Sciaridae).
abstract: DNA puffs are genomic regions of polytene chromosomes that undergo developmentally controlled DNA amplification and transcription in salivary glands of sciarid flies. Here, we tested the hypothesis that DNA puff genes code for salivary proteins in Trichosia pubescens. To do that, we generated antibodies against saliva and immunoscreened a cDNA library made from salivary glands. We isolated clones corresponding to DNA puff regions, including clone D-50 that contained the entire coding sequence of the previously isolated C4B1 gene from puff 4C. Indeed, we showed that puff 4C is a DNA puff region detecting its local transcription and its extra rounds of DNA incorporation compared to neighboring regions. We further confirmed D-50 clone identity in Western blots reacted with the anti-saliva anitiserum. We detected a recombinant protein expressed by this clone that had the expected size for a full-length product of the gene. We end with a discussion of the relationship between DNA puff genes and their products.
authors: Departamento de Genética e Biologia Evolutiva, Instituto de Biociências, Universidade de São Paulo, São Paulo, Brazil. lpma@ib.usp.br
authors: Luiz Paulo
authors: LP
authors: Andrioli
authors: Eduardo
authors: E
authors: Gorab
authors: José Mariano
authors: JM
authors: Amabis
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D000906:Antibodies / Q000378:metabolism; D001483:Base Sequence; D015153:Blotting, Western; D002875:Chromosomes / Q000378:metabolism / Q000648:ultrastructure; D004261:DNA Replication / Q000235:genetics; D018076:DNA, Complementary / Q000737:chemistry; D004175:Diptera / Q000235:genetics* / Q000378:metabolism; D005260:Female; D015870:Gene Expression / Q000235:genetics*; D015723:Gene Library; D019476:Insect Proteins / Q000235:genetics* / Q000378:metabolism; D008297:Male; D051379:Mice; D008969:Molecular Sequence Data; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000378:metabolism; D012471:Salivary Proteins and Peptides / Q000235:genetics* / Q000378:metabolism; D013936:Thymidine / Q000378:metabolism; D013997:Time Factors; D014316:Tritium / Q000032:analysis
chemical_list: D000906:Antibodies; D018076:DNA, Complementary; D019476:Insect Proteins; D011994:Recombinant Proteins; D012471:Salivary Proteins and Peptides; D014316:Tritium; D013936:Thymidine