EP0223399B1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Effecting somatic changes in plants through the use of negative strand RNAS
Assignee: Monsanto Co
•
Filing: 1986-10-10
•
Granted: 1994-04-20
•
Expires: 2006-10-10
Abstract
Abstract A strategy is disclosed for effecting useful somatic changes in plants by causing the transcription in the plant cells of negative RNA strands which are substantially complementary to a target RNA strand. The target RNA strand can be an mRNA transcript created in gene expression, a viral RNA, or other RNA present in the plant cells. The negative RNA strand is complementary to at least a portion of the target RNA strand to inhibit its activity in vivo.
Inventors
- 👤 Francis P. Mccormick
- 👤 Kenneth A. Barton
- 👤 William F. Swain
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-07 13:55
CPC Classifications
C; C12; C12N; C12N15/00; C12N15/09; C12N15/11; C12N15/113; C12N15/1131; C12N15/1137; C12N15/63; C12N15/79; C12N15/82; C12N15/8216; C12N15/8218; C12Y; C12Y105/00; C12Y105/01; C12Y105/01019; C12N2310/00; C12N2310/10; C12N2310/11; C12N2310/111
Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
125 words
A method for effecting somatic changes in higher plants comprising the step of: introducing into a plant a DNA sequence including a promoter normally operable in plant cells and a coding sequence located 3' of the promoter, the orientation of the coding sequence being reversed relative to the promoter from its normal reading direction, which coding sequence causes transcription of a negative strand RNA having sufficient complementarity to an endogenous target RNA strand; or introducing into a plant a DNA sequence which causes the transcription of a negative strand RNA having sufficient complementarity to a target pathogenic RNA strand; sufficient complementarity being such that the negative strand RNA will effectively bind to the target RNA strand to inhibit target RNA strand activity in vivo .
Claim 2
Dependent Claim
27 words
A method as claimed in claim 1 wherein the target RNA strand is a messenger RNA and the inhibited activity is the expression of an endogenous protein.
Claim 3
Dependent Claim
21 words
A method as claimed in claim 1 wherein the target RNA strand is at least a portion of a pathogen RNA.
Claim 4
Dependent Claim
19 words
A method as claimed in claim 3 wherein the target RNA strand is the RNA of tobacco mosaic virus.
Claim 5
Dependent Claim
108 words
A method as claimed in claim 1 wherein the step of introducing the DNA sequence into the plant comprises the steps of constructing in a bacterium an expression vector plasmid including a promoter normally operable in plant cells and a DNA sequence coding for at least a portion of the target DNA located 3' of the promoter, the orientation of the DNA sequence being reversed relative to the promoter from its normal reading direction, transforming plant cells in culture with the expression vector from the expression vector plasmid, so that the transformed plant cells transcribe the negative RNA strand, and regenerating the transformed plant cells into whole plants.
Claim 6
Dependent Claim
39 words
A method as claimed in claim 5, wherein the transforming step includes the steps of conjugating the expression vector host with A. tumefaciens ; selecting for A. tumefaciens transconjugants; and infecting plant cells with the selected A. tumefaciens .
Claim 7
Dependent Claim
101 words
A chimeric gene construction operable in plants characterised in that it comprises a promoter sequence normally operable in plant cells; and a DNA coding sequence located 3' of the promoter and coding for at least a portion of a target RNA strand normally active in plant cells, the orientation of the DNA coding sequence being reversed relative to the promoter from its normal transcription direction so that the chimeric gene causes transcription of a negative strand RNA complementary to at least a portion of the target RNA strand so as to inhibit activity of the target RNA strand in vivo .
Claim 8
Dependent Claim
26 words
A chimeric gene as claimed in claim 7, characterised by further comprising a polyadenylation sequence normally operable in plants located 3' of the DNA coding sequence.
Claim 9
Dependent Claim
19 words
A morphologically normal plant comprising in its genome a chimeric gene construction as claimed in claim 7 or 8.
Claim 10
Dependent Claim
24 words
A seed of a morphologically normal plant, said seed comprising in its genome a chimeric gene construction as claimed in claim 7 or 8.
References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.