This Article Full Text (PDF) Alert me when this article is cited Alert me if a correction is posted Services Email this article to a friend Similar articles in this journal Similar articles in Web of Science Similar articles in PubMed Alert me to new issues of the journal Download to citation manager Citing Articles Citing Articles via CrossRef Citing Articles via Web of Science (6) Citing Articles via Google Scholar Google Scholar Articles by Gomez-Navarrete, G. Articles by Moore, T. C. Search for Related Content PubMed PubMed Citation Articles by Gomez-Navarrete, G. Articles by Moore, T. C. Agricola Articles by Gomez-Navarrete, G. Articles by Moore, T. C.

Articles

Effects of Protein Synthesis Inhibitors on ent-Kaurene Biosynthesis during Photomorphogenesis of Etiolated Pea Seedlings ¹

Department of Botany and Plant Pathology, Oregon State University, Corvallis, Oregon 97331

Excised shoot tips from 10-day-old etiolated pea (Pisum sativum L. cv. Alaska) seedlings were incubated in solutions of chloramphenicol, cycloheximide, and lincomycin at different concentrations during periods of 0, 4, 8, and 12 hours of irradiation with high intensity white light. Enzyme extracts were prepared from the whole shoot tips and compared with extracts from nontreated shoot tips for their capacity to synthesize ent-kaurene from mevalonate. In control samples, kaurene synthesis increased during the first 8 hours of irradiation and decreased after 12 hours. Chlorophyll content increased steadily up to 12 hours of irradiation. Chloramphenicol and cycloheximide reduced both kaurene synthesis and chlorophyll formation to a similar extent during all periods of irradiation, the reduction being greatest after 8 hours of irradiation. Lincomycin, a specific inhibitor of the formation of chloroplast ribosomes in detached pea shoot tips, did not significantly affect kaurene synthesis activity but strongly inhibited chlorophyll formation. It is tentatively concluded that the increase in kaurene synthesis activity during normal photomorphogenesis in pea seedlings is due to photoinduction of de novo synthesis of one or more proteins involved in the biosynthetic pathway from mevalonate to kaurene.

³ Author to whom inquiries should be made.

¹ This work constitutes a portion of a thesis presented by G. G.-N. to the Graduate School of Oregon State University in partial fulfillment of the requirements for the M.S. degree. The investigations were supported in part by a scholarship awarded by the Latin American Scholarship Program of American Universities to the senior author and by Grant PCM75-22119 from the National Science Foundation.