Enhancement of soybean RNA polymerase I by auxin.
When etiolated soybean seedlings are treated with the synthetic auxin, 2,4-dichlorophenoxy-acetic acid, cells of the mature hypocotyl become swollen and proliferate abnormally. This abnormal growth induced by auxin coincides with a 5- to 8-fold increase in the alpha-amanitin-insensitive RNA polymerase associated with isolated chromatin or nuclei. The alpha-amanitin-sensitive RNA polymerase activity of the auxin-treated hypocotyl was similar to that of control tissue. The increase in RNA polymerase I activity of chromatin and nuclei was maintained after solubilization and fractionation on DEAE-cellulose. Auxin thus appears to enhance RNA synthetic activity (i.e., ribosomal RNA) in mature soybean tissue by altering RNA polymerase I directly rather than by altering RNA polymerase I directly rather than by altering the chromatin template.
D015084:2,4-Dichlorophenoxyacetic Acid / Q000494:pharmacology; D002455:Cell Division / Q000187:drug effects; D002458:Cell Fractionation; D002467:Cell Nucleus / Q000201:enzymology; D002843:Chromatin / Q000201:enzymology; D002848:Chromatography, DEAE-Cellulose; D012321:DNA-Directed RNA Polymerases / Q000378:metabolism*; D007210:Indoleacetic Acids / Q000494:pharmacology*; D010937:Plant Growth Regulators / Q000494:pharmacology*; D010944:Plants / Q000201:enzymology; D012335:RNA, Ribosomal / Q000096:biosynthesis; D013025:Glycine max
D002843:Chromatin; D007210:Indoleacetic Acids; D010937:Plant Growth Regulators; D012335:RNA, Ribosomal; D015084:2,4-Dichlorophenoxyacetic Acid; D012321:DNA-Directed RNA Polymerases