Promoters and UAS from opine synthase genes
The Biotechnology Research and Development Corporation and the Purdue Research Foundation co-own patents granted in the U.S., Australia and Russia. The United States and the Australian patents are directed to chimeric regulatory regions containing promoters and UAS derived from the opine genes mas and ocs of Agrobacterium tumefaciens. The UAS are essential for the transcription of the opine genes in natural conditions. The promoters of mas and ocs are themselves weak promoters, but linking UAS regions to them increases their activity and they behave in a more constitutive fashion.
Definition of promoter and UAS
A UAS is defined in these patents in functional terms as a cis-acting element that in the native state is usually at least 100 bp upstream of the native transcriptional start site and can exert influence on gene expression.
A promoter is not precisely defined in the specification, but it is referred to as a DNA sequence required for the transcription of genes that contains a functional TATA box and which directs the expression of a gene. Thus, the promoter has both structural and functional elements.
Approximate scope of protection
The chimeric regulatory regions claimed in the U.S. patent combine promoters and UAS elements as follows:
- a promoter and an UAS from a mas gene and at least one UAS from an ocs gene;
- a promoter from a mas gene and at least 3 UAS elements from an ocs gene; and
- a promoter and an UAS from a mas gene and at least 3 UAS elements from an ocs gene.
The Australian patent claims more combinations of promoters and UAS elements than the U.S. patent. In contrast with the U.S. patent, the promoters and UAS of some of the regulatory regions claimed in the Australian patent derive from any opine synthase gene. It also includes a claim to a regulatory region formed by a promoter and a UAS, both derived from amas gene.
Cassettes and methods for the expression of a foreign gene in a plant using the described chimeric regulatory regions are also claimed in both the U.S. and the Australian patents. Some of the cassettes are used for inducible expression of a gene of interest in a plant. Transgenic plants containing some of the cassettes are also claimed.
Some bibliographic data and a summary of the independent claims of the granted patents are presented in the table on the following page.