Light-inducible promoters

The United States patent US 5750385 assigned to Calgene Inc, does not specifically claim a single, individual light-inducible promoter. Rather, the patent claims the use of a promoter activated by light in order to control expression of a gene introduced into plants by transformation. In at least some cases, the phenotype of the tissue expressing the gene is modified.

The specification of the patent discloses promoters such as fruit-specific and seed specific. Related patents (US 5420034US 5753475 and US 6281410) have claims directed to these aspects. The claims in the instant patent are directed only to induced gene expression or modification of the phenotypic property in transformed plants as a result of light induced processes in chloroplasts.

The patent specification makes particular reference to the promoter from the soybean SSU gene (small subunit SSU) of ribulose-1,5-bisphophate-carboxylase, although the claims are not so limited. Through the use of the soybean SSU promoter, the expression of the gene under its control can be light-induced. Thus in the presence of light, its expression is increased, while its expression is substantially reduced in the absence of light. Moreover, the vector construct may also include enhancers, operators, activators, or other regions involved with transcriptional regulation.

The patent claims methods for obtaining a transformed plant with a modified phenotype or for altering the phenotype of transformed plant tissues containing chloroplasts using a vector construct comprising:

  • a promoter region from a gene that is light-inducible in a chloroplast-co ntaining tissue,
  • DNA sequence of interest, and
  • a transcription termination region.

In dependent claims, the promoter is from a soybean SSU gene, and the plant is soybean, tomato, or rapeseed. Because the claims do not limit the source of the light-inducible promoter, the Calgene assigned patent has the broadest scope in the patent landscape surrounding light-inducible promoters.

Calgene Inc. was bought by Monsanto in 1996 and therefore its patents are probably now controlled by Monsanto(

Specific Patent Information

Patent Number Title, Independent Claims and Summary of Claims Assignee
US 5750385

  • Earliest priority – 17 January 1985
  • Filed – 7 June 1995
  • Granted 12 May 1998
  • Expected expiry – 12 May  2015
Title – Methods and compositions for regulated transcription and expression of heterologous genes.

Claim 1
A method for obtaining a plant having a modified phenotype, said method comprising:transforming a host plant cell with a DNA construct under genomic integration conditions, wherein said construct comprises as operably linked components in the direction of transcription,
a promoter region obtainable from a gene, wherein transcription of said gene is light-inducible in a plant chloroplast containing tissue,
a DNA sequence of interest other than the native coding sequence of said gene, and
a transcription termination region, wherein said components are functional in a plant cell, whereby said DNA construct becomes integrated into a genome of said plant cell;

regenerating a plant from said transformed plant cell, and

growing said plant under conditions whereby said DNA sequence of interest is expressed and a plant having said modified phenotype is obtained.

Claim 2
A method for altering the phenotype of chloroplast containing plant tissue as distinct from other plant tissue, said method comprising:growing a plant, wherein said plant comprises cells containing a DNA construct integrated into their genome, said DNA constructcomprising, in the 5′ to 3′ direction of transcription,
a transcriptional initiation region from a gene, wherein transcription of said gene is light-inducible in a plant chloroplast containing tissue,
a DNA sequence of interest other than the coding sequence native to said transcriptional initiation region, and
a transcriptional termination region, whereby said DNA sequence of interest is transcribed under transcriptional control of said transcriptional initiation region and a plant having an altered phenotype is obtained.

The claims are generally directed to methods for transforming plants for a modified phenotype using a DNA construct. The construct comprises a promoter that provides for light-inducible transcription in either a specific plant tissue or a plant part. Transcription may be induced during a particular stage of growth or in response to an external stimulus.

Calgene Inc.

Note: Patent information was last updated on 11 May 2006. Search terms: “Promoter” in abstract and “Calgene” in applicant. Patent database: PatentLens in combination with INPADOC.

University of Warwick had granted patents in Europe (EP 310619) and Canada (CA 1321563) regarding a light inducible promoter. The claims are generally related to a DNA sequence comprising a promoter isolated from myxobacterium. The promoter is linked to a sequence further containing a restriction site for the insertion of a desired sequence. A method of producing a polypeptide under the control of the myxobacterium promoter is also claimed but limited to a transformed bacterial host.

However, the fact that both the European and the Canadian patents lapsed and the related Australian patent application (AU 75421/87) also lapsed suggested that this patent family had been abandoned.