title: Alteration of Ringer pH and its effects on precursor incorporation into Drosophila salivary gland nuclei.
abstract: Drosophila salivary glands were explanted and incubated with 3-H-uridine (or 3-H-thymidine) in Ringer's solution (Ephrussi-Beadle modified saline) adjusted to pH values in the integral range, 4 to 10. The results of autoradiographic investigations indicate a differential effect of altering Ringer pH on 3-H-uridine as opposed to 3-H-thymidine incorporation: a) Relatively uniform levels of chromosomal incorporation of 3-H-thymidine occured over the range of test pH. Some decrease of incorporation was noted at pH 5 and some increase at pH 9. b) Chromosomal incoroporation of 3H-uridine was severely depressed at pH 4 and 7 relative to the high incorporation levels observed at other pH values. Controlling pH of Ephrussi-Beadle Ringer's solution in such experiments a necessity. This appears especially important for studies involving 3-H-uridine incorporation.
mesh_terms: D000818:Animals; D001345:Autoradiography; D002467:Cell Nucleus; D002478:Cells, Cultured; D002875:Chromosomes; D004331:Drosophila melanogaster / Q000033:anatomy & histology*; D006863:Hydrogen-Ion Concentration; D007553:Isotope Labeling; D012469:Salivary Glands / Q000166:cytology*; D012996:Solutions; D013936:Thymidine; D014316:Tritium; D014529:Uridine
chemical_list: D012996:Solutions; D014316:Tritium; D013936:Thymidine; D014529:Uridine