Genetic transformation of plants allows the introduction of genes of any origin into the target species providing novel products for e.g. agricultural, horticultural, nutritional and chemical applications. Furthermore, transgenic plants provide more information about basic plant biology, gene function and regulation. In many plant species, traditional plant breeding is limited due to the fact that the existing gene pool is narrow and prevents further development. Alteration of single characteristics can be time-consuming and even impossible without changing any other properties. Major applications of genetic transformation focus on the improvement of for example disease resistance, insect resistance, herbicide tolerance, modified quality characteristics such as modification of oil and protein compositions as well as on improving stress tolerance and modifying growth characteristics. In other applications transgenic plants are used as bioreactors for producing foreign proteins or plant secondary metabolites.
Several vector systems have been developed to be used in higher plants for transferring genes into plant tissue e.g. the use of plant viruses as vectors, direct gene transfer using DNA fragments not attached to a vector and Agrobacterium-mediated gene transformation.
Agrobacterium-mediated gene transformation is the most widely used method to transfer genes in plants using either Agrobacterium tumefaciens or Agrobacterium rhizogenes. Several Agrobacterium-mediated systems and methods for transforming plants and plant cells have been disclosed for example in WO 84/02920, EP 289478, U.S. Pat. No. 5,352,605, U.S. Pat. No. 5,378,619, U.S. Pat. No. 5,416,011, U.S. Pat. No. 5,569,834, U.S. Pat. No. 5,959,179, U.S. Pat. No. 6,018,100, and WO 00/42207.
Many of said methods are especially applied for oil crops such as Brassicaceae including Brassica rapa ssp. oleifera (Radke et al., Plant Cell Rep. 11:499-505, 1992) and Brassica campestris (Kuvshinov et al. Plant Cell Rep. 18:773-777, 1999). U.S. Pat. No. 5,188,958, U.S. Pat. No. 5,463,174 and U.S. Pat. No. 5,750,871 disclose the transformation of Brassica species using Agrobacterium-mediated transformation system. However, the conditions described in these publications do not give successful transformation result with Camelina sativa. 
Several transformation strategies utilizing the Agrobacterium-mediated transformation system have been developed. The binary vector strategy is based on a two-plasmid system where T-DNA is in a different plasmid from the rest of the Ti plasmid. In the cointegration strategy a small portion of the T-DNA is placed in the same vector as the foreign gene, which vector subsequently recombines with the Ti plasmid.
The production of transgenic plants has become routine for many plant species, but no universal transformation method for different plant species exists, since transformation and regeneration capacity varies among species and even with different explants. However, there is a need for developing alternative transformation systems and methods especially in oil crop. Camelina sativa (gold of pleasure or false flax), one of the most important oil crops in Europe during bronze and iron age, has been grown in Europe for centuries. It was especially used to production of lamp oil, but also in edible products. Oil products obtained from Camelina sativa have been used for producing food spreads as described in the U.S. Pat. No. 6,117,476.
Camelina sativa (L. Crantz) belongs to the family Brassicaceae in the tribe Sisymbrieae and both spring- and winter forms are in production. It is a low-input crop adapted to low fertility soils. Results from long-term experiments in Central Europe have shown that the seed yields of Camelina sativa are comparable to the yields of oil seed rape.
Due to the high oil content of Camelina sativa seeds varying about 30-40%, there has been a renewed interest in Camelina sativa oil. Camelina sativa seeds have a high content of polyunsaturated fatty acids, about 50-60% with an excellent balance of useful fatty acids including 30-40% of alpha-linolenic acid, which is omega-3 oil. Omega-3 oils resemble marine oils and are rarely found in other oil crops. Furthermore, Camelina sativa seed contains a high amount of tocopherols (appr. 600 ppm) with a unique oxidative stability. Moreover, the oil is low in glucosinolates (Matthäus and Zubr, Industrial Crops and Products 12:9-18, 2000). A quality problem for food and feed uses of Camelina sativa is that it contains relatively high amount of erucic acid (2-4%) and 11-eicosenoic acid (gondoic acid). Erucic acid is poorly digested and causes myocardial lesions in animals. Said problem causing erucic and 11-eicosenoic acids can be removed from the oil and used for other non-nutritional applications, which include the use of high-erucic acid containing oils as lubricants. Industrial applications might require prominence of such fatty acid of singular importance.
As Camelina sativa is a minor crop species, very little has been done in terms of its breeding aside from testing different accessions for agronomic traits and oil profiles. A mutation breeding experiment to induce variation in the fatty acid profiles has reported three to four fold differences (Buchsenschutz-Northdurft et al., 3rd European Symposium on Industrial Crops and Products, France, 1996). Applications of tissue culture techniques to Camelina sativa are restricted to two approaches. Camelina sativa has been used in a somatic fusion with other Brassica species (Narasimhulu et al., Plant Cell Rep. 13:657-660, 1994; Hansen, Crucifer. News 19:55-56, 1997; Sigareva and Earle, Theor. Appl. Genet. 98:164-170, 1999) and regenerated interspecific hybrid plants were obtained (Sigareva and Earle, Theor. Appl. Genet. 98:164-170, 1999). Recently, Camelina sativa shoots have been regenerated from leaf explants (Tattersall and Millam, Plant Cell Tissue and Organ Culture 55:147-149, 1999).
Present invention provides a genetic transformation system for Camelina sativa, which would address rapid improvement of this crop for different end-uses, which include the production of homologous and heterologous recombinant DNA products. Examples of homologous recombinant products comprise e.g. unique protein or oil products which are specific for Camelina sativa, whereas heterologous products include foreign proteins, enzymes, etc.
Another embodiment of the present invention is to provide a novel model plant for replacing e.g. Arabidopsis and tobacco.
A further embodiment is to provide transgenic Camelina sativa plants, plant tissue, plant cells and cell lines and seed.
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