Modified ubiquitin regulatory system
A modified ubiquitin regulatory system which lacks heatshock elements and so is not heat inducible can be used to regulate expression of a structural gene under the control thereof, e.g. by introducing an appropriate DNA construct into plant tissue.
1. An isolated DNA sequence comprising a ubiquitin regulatory system lacking heat shock elements wherein the ubiquitin regulatory system comprises the nucleotide sequence according to SEQ.ID.NO. 8.
2. A DNA construct comprising the DNA sequence of claim 1 operably linked to a plant-expressible structural coding sequence.
3. An expression vector comprising a DNA construct in accordance with claim 2 .
4. A method of transforming a host cell by introducing into the cell the DNA sequence of claim 1 , the DNA construct of claim 2 or the expression vector of claim 3 .
5. A method according to claim 4 wherein the host cell is a plant cell.
6. A host cell transformed with the DNA sequence of claim 1 , the DNA construct of claim 2 , or the expression vector of claim 3 .
7. A method of expressing a structural sequence in a host cell in a constitutive manner comprising transforming the host cell with the DNA sequence of claim 1 , the DNA construct of claim 3 , or the expression vector of claim 3 , wherein the structural coding sequence is constitutively expressed in the host cell.
8. A transgenic plant comprising the DNA sequence of claim 1 , the DNA construct of claim 2 , or the expression vector of claim 3 .
9. The transgenic plant of claim 8 wherein the plant is a monocot selected from the group consisting of wheat, barley, oat, corn or maize.
10. A transgenic plant seed comprising the DNA sequence of claim 1 , the DNA construct of claim 2 , or the expression vector of claim 3 .