Poster: Emerging Technologies
Abs #
887: Toward introduction of single-copy transgenes in sugarcane
|
|
Presenter: |
Wang, Ming-Li , mwang@harc-hspa.com |
Authors | Wang, Ming-Li (A) Goldstein, Cindy S (A) Moore, Paul H (B) Albert, Henrik H (B) | | Affiliations: |
(A): Hawaii Agriculture Research Center
(B): Pacific Basin Agricultural Research Center, United States Department of Agriculture, Agricultural Research Service
|
|
|
A high level of post-transcriptional gene silencing in sugarcane [1] is a major barrier to its development as a biofactory crop. More than 400 sugarcane lines, transformed by bombardment with human granulocyte macrophage colony stimulating factor (GMCSF) whole plasmid DNA, accumulated the recombinant protein at <0.1% of total protein. Because high transgene copy numbers and complex integration patterns commonly occur with gene gun bombardment and are often associated with high levels of transgene silencing, we are evaluating alternatives for single- or low-copy introduction of transgenes, in attempts to reduce transgene silencing. Alternatives include the use of insert-only DNA for bombardment [2], Cre/lox site-specific recombination to resolve multiple transgene copies [3, 4], and the Ac/Ds transposon system to direct transgene integration by transposition [5]. Although linear expression cassette only DNA produced a high frequency of low copy transgene insertions with no evidence of silencing through the R4 generation of rice [2], we observed that only 3 of 27 selected plants containing three or fewer copies. Accumulation of GMCSF in the low copy lines was not higher than multi-copy lines. Sugarcane lines produced by the other gene introduction methods are undergoing selection.
1. Wei, H., et al. J Plant Physiol, 2003. accepted.
2. Fu, X., et al. Transgenic Res, 2000. 9(1): p. 11-19.
3. Srivastava, V., O.D. Anderson, and D.W. Ow. Proc Natl Acad Sci U S A, 1999. 96(20): p. 11117-21.
4. Srivastava, V. and D.W. Ow. Plant Molecular Biology, 2001. 46(5): p. 561-566.
5. Koprek, T., et al. Plant Physiol, 2001. 125(3): p. 1354-62.
