title: The effect of ecdysterone on nonhistone proteins in salivary gland chromosomes of Sciara coprophila.
abstract: Synthesis and transport of proteins to the cell nucleus during puff induction was studied in S. coprophila. Changes in grain distribution along chromosomes (L-methionine [35S] incorporation into protein) were correlated with puffs induced by ecdysterone in vitro; A pattern of specific labelling at the sites of incipient puffs was noted within 2 h after the addition of the hormone, i.e. grains on the chromosomes were in clusters, characteristic for this time point and not seen in the controls (where only non-specific labeling was noted 0-4 h). Characteristic chromosomal puffs appeared between 3-4 h after the addition of ecdysterone. It was concluded that during ecdysterone-induced puff formation in salivary gland chromosomes, proteins which had been previously synthesized were selectively transported from the cytoplasm to specific sites on the chromosomes.
mesh_terms: D000818:Animals; D001692:Biological Transport / Q000187:drug effects; D002868:Chromosomal Proteins, Non-Histone / Q000096:biosynthesis / Q000378:metabolism*; D002875:Chromosomes / Q000187:drug effects* / Q000378:metabolism; D003513:Cycloheximide / Q000494:pharmacology; D004247:DNA / Q000096:biosynthesis; D004175:Diptera / Q000187:drug effects* / Q000378:metabolism; D004441:Ecdysterone / Q000494:pharmacology*; D005260:Female; D012313:RNA / Q000096:biosynthesis; D012469:Salivary Glands / Q000648:ultrastructure
chemical_list: D002868:Chromosomal Proteins, Non-Histone; D004441:Ecdysterone; D012313:RNA; D004247:DNA; D003513:Cycloheximide