RNA-Mediated RNA Degradation and Chalcone Synthase A Silencing in Petunia

• Published in: Cell Vol. 88; no. 6; pp. 845 - 854
• Main Authors: Metzlaff, M, O'Dell, M, Cluster, P.D, Flavell, R.B
• Format: Journal Article
• Language: English
• Published: United States Elsevier Inc 21-03-1997
• Subjects: Acyltransferases - genetics; Blotting, Northern; Endoribonucleases - metabolism; Gene Expression Regulation, Enzymologic - physiology; Gene Expression Regulation, Plant - physiology; Genes, Plant - physiology; Molecular Sequence Data; Nucleic Acid Conformation; Nucleic Acid Hybridization; Petunia; Phenotype; Plant Leaves - enzymology; Plant Leaves - genetics; Plants, Genetically Modified - physiology; Polymerase Chain Reaction; RNA, Double-Stranded - metabolism; RNA, Messenger - analysis; RNA, Messenger - chemistry; RNA, Messenger - physiology; RNA, Plant - chemistry; RNA, Plant - genetics; RNA, Plant - metabolism; Transcription, Genetic - physiology; Transgenes - physiology
• ISSN: 0092-8674; 1097-4172
• DOI: 10.1016/S0092-8674(00)81930-3

Transgenic Petunia plants with a
chsA coding sequence under the control of a 35S promoter sometimes lose endogene and transgene chalcone synthase activity and purple flower pigment through posttranscriptional
chsA RNA degradation. In these plants, shorter poly(A)
+ and poly(A)
−
chsA RNAs are found, and a 3′ end–specific RNA fragment from the endogene is more resistant to degradation. The termini of this RNA fragment are located in a region of complementarity between the
chsA 3′ coding region and its 3′ untranslated region. Equivalent
chsA RNA fragments remain in the white flower tissue of a nontransgenic Petunia variety. We present a model involving cycles of RNA–RNA pairing between complementary sequences followed by endonucleolytic RNA cleavages to describe how RNA degradation is likely to be promoted.