US 7,842,853 B2 · Transgenic plants synthesizing high amylose starch

Abstract

Transgenic plant cells and plants are described which synthesise a starch which is modified in comparison with corresponding wild type plant cells and plants. The plant cells and plants described show a reduced activity of R1, BEI and BEII proteins. Furthermore, modified starches as well as methods for their production are described.

An isolated starch comprising an amylose content of at least 75% and a phosphate content which is reduced by at least 50% in comparison to starch from corresponding wild type potato plant cells,

wherein said starch is derived from transgenic potato plant cells comprising
(1) a first foreign nucleic acid molecule comprising
(a) a nucleic acid sequence comprising at least 500 nucleotides of a starch phosphorylating (R1) gene operably linked to a promoter in an antisense orientation leading to reduced expression of an endogenous gene encoding a R1 protein compared to expression in the non-transgenic potato plant cell;
(b) a nucleic acid sequence comprising at least 500 nucleotides of a starch phosphorylating (R1) gene which, via a co-suppression effect, reduces the expression of an endogenous gene encoding a R1 protein compared to expression in the non-transgenic potato plant cell;
or
(c) a nucleic acid sequence comprising at least 500 nucleotides of a starch phosphorylating (R1) gene that simultaneously encodes at least one antisense RNA and at least one sense RNA, where said antisense RNA and said sense RNA form a double-stranded RNA molecule that reduces the expression of at least one endogenous gene encoding a R1 protein compared to expression in the non-transgenic potato plant cell;
(2) a second foreign nucleic acid molecule comprising
(a) a nucleic acid sequence comprising at least 500 nucleotides of a branching enzyme I (BEI) gene operably linked to a promoter in an antisense orientation leading to reduced expression of an endogenous gene encoding a BEI protein compared to expression in the non-transgenic potato plant cell;
(b) a nucleic acid sequence comprising at least 500 nucleotides of a branching enzyme I (BEI) gene which, via a co-suppression effect, reduces the expression of an endogenous gene encoding a BEI protein compared to expression in the non-transgenic potato plant cell;
or
(c) a nucleic acid sequence comprising at least 500 nucleotides of a branching enzyme I (BEI) gene that simultaneously encodes at least one antisense RNA and at least one sense RNA, where said antisense RNA and said sense RNA form a double-stranded RNA molecule that reduces the expression of at least one endogenous gene encoding a BEI protein compared to expression in the non-transgenic potato plant cell;
and
(2) a third foreign nucleic acid molecule comprising
(a) a nucleic acid sequence comprising at least 500 nucleotides of a branching enzyme II (BEII) gene operably linked to a promoter in an antisense orientation leading to reduced expression of an endogenous gene encoding a BEII protein compared to expression in the non-transgenic potato plant cell;
(b) a nucleic acid sequence comprising at least 500 nucleotides of a branching enzyme II (BEII) gene which, via a co-suppression effect, reduces the expression of an endogenous gene encoding a BEII protein compared to expression in the non-transgenic potato plant cell;
or
(c) a nucleic acid sequence comprising at least 500 nucleotides of a branching enzyme II (BEII) gene that simultaneously encodes at least one antisense RNA and at least one sense RNA, where said antisense RNA and said sense RNA form a double-stranded RNA molecule that reduces the expression of at least one endogenous gene encoding a BEII protein compared to expression in the non-transgenic potato plant cell.

14 more elements

Description16,531 words

Summary12,802 words

#(a) Field of the Invention

#The present invention relates to genetically modified plant cells and plants wherein the genetic modification leads to the reduction of the activity of R1 and BEI and BEII proteins in comparison with corresponding plant cells of wild type plants that have not been genetically modified. Furthermore, the present invention relates to means and methods for the production thereof. Plant cells and plants of that type synthesise a modified starch characterised in that it has an amylose content of at least 75% and—in comparison with starch of corresponding wild type plants which have not been genetically modified—a reduced phosphate content and/or a modified distribution of the side chains and/or an increased gel strength in the texture analyser and/or a modified starch granule morphology and/or a modified average starch granule size. Thus, the present invention also relates to starch that can be synthesised by the plant cells and plants of the invention as well as methods for the production of this starch.

#(b) Description of the Related Art

Brief description of the drawings4 figures

#FIG. 1: Schematic representation of the expression vector ME 5/6 as described further below.

#FIG. 2: Light-microscopic view of starch granules of wild type potato plants.

#FIG. 3: Light-microscopic view of starch granules of 072VL036 potato plants having a reduced gene expression of the R1 and BEI gene.

Detailed description3,666 words

#The following Methods were Used in the Examples:

#Analysis of the Starch

#a) Determination of the Amylose/Amylopectin Ratio

Facts

Application

11/527,099Filed 25 Sep 2006 · division

Priority

DE 101 28 36312 Jun 2001

Published

US 2007/0174932 A126 Jul 2007

Granted

30 Nov 2010

Term ended

16 Oct 2024

Estimated · how

20 years from earliest known nonprovisional domestic filing plus recorded patent term adjustment, including 858 days of adjustment. Maintenance-fee lapses, terminal disclaimers and statutory extensions have not been checked. The continuity chain may be incomplete; this is not an enforceability determination.

Classification5 codes

C12N 9/1051
Glycosyltransferases: hexosyltransferases
C07K 14/415
Peptides having more than 20 amino acids; Gastrins; Somatostatins; Melanotropins; Derivatives thereof: from plants
C12N 15/8245
Involving biosynthetic or metabolic pathways, i.e. metabolic engineering, e.g. nicotine, caffeine: involving modified carbohydrate or sugar…
C12N
Microorganisms or enzymes

Timeline

12 Jun 2001Priority claimedDE 101 28 363
25 Sep 2006Application filedUS 11/527,099
25 Jun 2007Assigned to Bayer Cropscience GmbHassignment of assignor's interest
26 Jul 2007PublishedUS 2007/0174932 A1
16 Oct 2007Assigned to Bayer Cropscience AGchange of name
30 Nov 2010GrantedUS 7,842,853 B2
2 Apr 2015Assigned to Bayer Intellectual Property GmbHassignment of assignor's interest
9 May 2019Assigned to BASF Agricultural Solutions Seed, US LLCassignment of assignor's interest
16 Oct 2024Term endedEstimated, includes 858 days of adjustment

Transgenic plants synthesizing high amylose starch

Life of this patent

Transgenic plants synthesizing high amylose starch

Life of this patent

Life of this patent

Abstract

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Drawings

Claims13

Description16,531 words

Drawings

Classification5 codes

Life of this patent

Description16,531 words