Weight reduction of the transformed plant tissue

Patent applications filed by Monsanto

During co-cultivation of plant tissue with Agrobacterium it is desirable to reduce the weight of the explant in order to facilitate the DNA transfer process and the formation of embryogenic callus.

Monsanto‘s disclosure teaches methods for reducing the weight of the explant during the co-cultivation period. Preferred methods of the inventors include reduction of moisture conditions, applying vacuum, increasing the osmotic potential of the media by use of mannitol, sorbitol or polyethylene glycol, air drying the explant by evaporation or applied air, or applying chemicals (desiccants) such as calcium oxide to extract moisture from the explant.

Specific Patent Information

Patent Number Title, Independent Claims and Summary of Claims Assignee
US 2001/054186 AA

  • Earliest priority – 11 December 1998
  • Filed – 10 December 1999
  • Published – 20 December 2001
  • Expected expiry – N/A
  • Status -pending

WO 200034491 A2

  • Earliest priority – 11 December 1998
  • Filed – 9 December 1999
  • OPI – 15 June 2000
  • Expected expiry – N/A
Title – An improved efficiency Agrobacterium-mediated plant transformation method

Claim 1
A method for producing a fertile transgenic plant, comprising the steps of:(a) introducing one or more genetic component(s) one desires to introduce into the genome of a plant by co-culturing a regenerable plant cell or tissue with Agrobacterium containing said genetic component(s);
(b) co-culturing said Agrobacterium and regenerable plant cells or tissues of step (a) under conditions that decrease the weight of saidArobacterium-inoculated explant;
(c) identifying or selecting a transformed cell line; and
(d) regenerating a fertile transgenic plant therefrom.

The claims as filed of both the United States and PCT applications recite a method for producing a fertile transgenic plant by co-culturing a plant cell or tissue with Agrobacterium having the genes of interest under conditions that decrease the weight of the explant. The transformed cell lines are selected and regenerated into a fertile transgenic plant.

According to the specification, the method to reduce the weight of the inoculated explant ‘comprises any method that reduces the weight of the inoculated explant and facilitates the DNA transfer process.’

Preferred methods to reduce the weight of the explant are (but not limited to):

  • restricting exogenous moisture to the explant during co-culture
  • reducing the weight of the explant by applying a vacuum during co-culture
  • increasing the osmotic potential of the media, for example, by use of mannitol, sorbitol, raffinose, or polyethylene glycol or combinations thereof
  • air drying the explant to reduce the weight of the explant by evaporation or applied air
  • chemical means of extracting moisture from the explant during co-culture, for example, by placing the explant in a dessicating environment
Monsanto
AU 773764

  • Earliest priority – 11 December 1998
  • Filed – 9 December 1999
  • Granted – 3 June 2004
  • Expected expiry – 8 December 2019
Title – An improved efficiency Agrobacterium-mediated plant transformation method

Claim 1

A method for producing a fertile transgenic plant, comprising the steps of:

(a) introducing one or more genetic component(s) into the genome of a plant by co-culturing a regenerable plant cell or tissue with Agrobacterium containing said genetic component(s);
(b) co-culturing said Agrobacterium and regenerable plant cells or tissues of step (a) in a manner controlling a reduction in the weight of said Agrobacterium-inoculated explant of from about 20% to 35% of the weight of the plant cell or tissue prior to co-culture, wherein the manner for controlling a reduction in the weight of the Agrobacterium-inoculted explant comprises limitation or removal of water from the explant;
(c) identifying or selecting a transformed cell line; and
(d) regenerating a fertile transgenic plant therefrom.

Granted AU 773764 recites a method for producing a fertile transgenic plant using Agrobacterium, where the method of weight reduction of the inoculated explant is limited to ‘limitation or removal of water from the explant‘.

Remarks
  1. National phase entries of WO 2000/34491 in Canada (CA 2353796), Europe (EP 1137790) and Japan (JP 2002531132) are pending.
  2. Other national phase entries of WO 2000/34491 include: Brazil (BR 9916103), South Africa (ZA 200104091).

Note: Patent information on this page was last updated on 7 March 2006.