Studies on differentiation without cleavage in Chaetopterus variopedatus: requirements for nucleic acid and protein synthesis.

Activation of unfertilized Chaetopterus eggs by treatment with an excess of KCl may lead to the production of unicellular ciliated larvae (Lillie's differentiation without cleavage). The effects of a number of inhibitors of protein (puromycin, cycloheximide, emetin), RNA (actinomycin D), and DNA (hydroxyurea) synthesis of differentiation without cleavage and on normal development have been studied in Chaetopterus. Incorporation of radioactive leucine, uridine, and thymine has been followed by biochemical methods and by autoradiography.

RNA-dependent DNA polymerase: possible role in the amplification of ribosomal DNA in Xenopus oocytes.

2',5' - dimethyl - N(4')benzyl - N(4') - [desmethyl]rifampicin, a derivative of rifampicin, is used to acquire autoradiographic evidence that RNA-dependent DNA synthesis is involved in gene amplification during the early oogenesis of Xenopus laevis.