|
Table 4. Genetic transformation
of wheat for pathogen and pest resistance.
|
Gene |
Source |
Mode of Action |
Construct (Promoter) |
Comment/Reference
|
|
Coat Protein |
Barley yellow mosaic virus |
Coat protein-mediated resistance |
pEmuPAT-cp (35S) |
|
|
Ribosome Inactivating protein (RIP) |
Hordeum vulgare |
Specific glycosidases that remove a conserved adenine residue from the large rRNA of the large ribosomal subunit Inactivates ribosome and blocks translation elongation |
pRipChi (Ubi)
I-Sec1 (35S-RTBV intron) |
Interfere with normal plant regeneration
and development (Bliffeld et al. 1999) Moderate/no protection against Erysiphe graminis (Bieri et al. 2000) |
|
Chitinase |
Oryza sativa |
Cell wall degradative enzyme Act on cell wall polysachharide, chitin |
pAHG11 Chi11_Ubi pro-bar-nos |
Lack of transgene expression (Chen et al. 1998; Chen et al. 1999) |
| Hordeum vulgare | Ubi | Increased resistance to infection by Erysiphe graminis (Bliffeld et al. 1999) | ||
|
Thaumatin like Protein (tlp) |
Oryza sativa |
Alter membrane permeability and/or |
pGL2ubi-tlp (Ubi/tlp/CaMV 35S/hpt) |
Enhanced resistance against Fusarium graminnearum in T1, T2 and T3 plants (Chen et al. 1999) |
|
Stilbene synthase |
Vitis vinifera |
Phytoalexin synthesis Synthesizes the phytoalexin trans-reveratrol |
pGBI, pGBII (Vst1) |
Induction of stilbene synthase mRNA after wounding and infection in T1 and T2 plants (Leckband and Lorz, 1998) |
|
Killer protein (KP) |
Ustilago maydis infecting virus |
Virally encoded antifungal protein. Inhibit growth of sensitive cells |
pUbi:KP4 (Ubi) |
Increased endogenous resistance against Tilletia tritici (Clausen et al. 2000) |
|
Lectin |
Galanthus nivalis agglutinin (GNA) |
Binding to the insect gut surface |
pRSsGNA (Rss1) pUbiGNA (Ubi) |
Decreases the fecundity, but not the survival of the grain aphid Sitobion avenae (Stoger et al. 1999) |
|
Proteinase Inhibitor |
Hordeum vulgare (Barley trypsin inhibitor-CMe) |
Regulators of endogenous proteinases Lower protease activity in insect guts leading to direct shortage of amino acids |
C-Me (BTI-CMe) |
Inhibition of early insect larvae in transgenic seeds; No significant effect on leaf feeding insects (Altpeter et al. 1999) |
|
|
Sagittaria trifolia [arrowhead proteinase inhibitor (API)] |
Serine proteinase inhibitor |
pBIAH-A(B) |
Introduction of arrowhead proteinase inhibitor genes into wheat genome by pollen tube pathway (Mu et al. 1999) |
|
Abbreviations: |
|
|