ABSTRACT

The disclosure provides a synthetic biology toolkit that enables precise and effective control of gene expression in A. tumefaciens and related Rhizobia. Inducible expression systems were constructed, characterized, and optimized to obtain an expression system regulated through amplifier introduction and promoter engineering, and cognate promoters were produced and evaluated. To establish a fine-tunability, a series of spacers and a promoter library were constructed to systematically modulate both translational and transcriptional rates. The application of the tools was demonstrated by coexpressing genes with altered expression levels using a single signal. The studies carried out provide precise expression tools, facilitating rational engineering of in A. tumefaciens and related Rhizobia bacteria for advanced plant biotechnological applications.

A plant material comprises a genomic nucleotide sequence encoding a SUSIBA2 or SUSIBA2-like transcription factor under transcriptional control of a promoter active in the plant material. The genomic nucleotide sequence encoding the SUSIBA2 or SUSIBA2-like transcription factor lacks at least a portion of an activation region of a SUSIBA1 or SUSIBA1-like promote represent in an intron of a wild-type version of the genomic nucleotide sequence encoding the SUSIBA2 or SUSIBA2-like transcription factor. The plant material has a controlled production of carbohydrates, in particular starch or starch and fructan. In particular, the plant material can be designed to produce carbohydrates at enhanced levels.

Synthetic signal transduction systems are provided. The synthetic signal transduction system may be a hormone degradable CRISPR-based transcription factor including a nuclease null Cas9 protein, a nuclear localization signal, a phytohormone degron, and a transcriptional regulation domain. Methods of generating non-naturally occurring plants are also provided. The methods may include expressing a synthetic signal transduction system in a plant. Non-naturally occurring plants formed by the methods are also provided.

In one aspect, the present application discloses a chimeric gene comprising (a) a first nucleic acid sequence comprising at least 400 consecutive nucleotides of SEQ ID NO: 1 or SEQ ID NO: 2 or a nucleic acid sequence having at least 80% sequence identity thereto any of which confers stress inducibility on said chimeric gene; (b) a second nucleic acid sequence encoding an expression product of interest, which is involved in the response of a cotton plant to stress; and optionally (c) a transcription termination and polyadenylation sequence. In another aspect, the application discloses a cotton plant cell comprising (a) a chimeric gene comprising a first nucleic acid sequence comprising at least 400 consecutive nucleotides of SEQ ID NO: 1 or SEQ ID NO: 2 or a nucleic acid sequence having at least 80 sequence identity thereto any of which confers stress inducibility on said chimeric gene; (b) a second nucleic acid sequence encoding an expression product of interest; and optionally (c) a transcription termination and polyadenylation sequence. In addition, the present application discloses a cotton plant, a method of expressing a transgene in cotton under stress conditions, a method of producing a cotton plant, a method of detecting the expression of a transgene under stress conditions and a method for modulating the resistance of a cotton plant to stress as characterized in the claims.

The present technology provides dominant negative forms of transcription factors for modifying nicotine biosynthesis and nucleic acid molecules that encode such dominant negative transcription factors. Also provided are methods of using these nucleic acids to modulate nicotine production in plants and for producing plants and plant cells having reduced nicotine content.

The present application provides novel algal regulatory elements including inducible nitrate/nitrite promoter sequences and terminator sequences. The application further discloses DNA constructs comprising these novel regulatory elements, and recombinant microorganisms comprising these regulatory elements. Methods of modifying, producing, and using the regulatory elements are also disclosed. Methods disclosed in the present application are suited for inducible expressions of genes, such as a transgene or a native gene in algal species.

This invention relates to systems, methods, and devices for inducing and/or repressing the expression of proteins. More particularly, the invention relates to systems, methods, and devices for inducing and/or repressing the expression of proteins in plastids. An exemplary embodiment involves the regulation of the expression of proteins involved in hydrogen production to stimulate the production of hydrogen gas using the methods, systems, and devices described herein.

The present application provides novel algal regulatory elements including inducible nitrate/nitrite promoter sequences and terminator sequences. The application further discloses DNA constructs comprising these novel regulatory elements, and recombinant microorganisms comprising these regulatory elements. Methods of modifying, producing, and using the regulatory elements are also disclosed. Methods disclosed in the present application are suited for inducible expressions of genes, such as a transgene or a native gene in algal species.

Provided are compositions comprising polynucleotides encoding BG1 polypeptides. Also provided are recombinant DNA constructs, plants, plant cells, seed, grain comprising the polynucleotides, and plants, plant cells, seed, grain comprising a BG1 polypeptide. Additionally, various methods of employing the polynucleotides and genetic modifications in plants, such as methods for increasing BG1 level in a plant and methods for increasing yield of a plant, nutrient utilization efficiency and/or drought tolerance, are also provided herein.