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Evaluation of selectable markers for obtaining stable transformants in the gramineae 总被引:13,自引:5,他引:8 下载免费PDF全文
Hauptmann RM Vasil V Ozias-Akins P Tabaeizadeh Z Rogers SG Fraley RT Horsch RB Vasil IK 《Plant physiology》1988,86(2):602-606
Cell suspension cultures of Triticum monococcum, Panicum maximum, Saccharum officinarum, Pennisetum americanum, and a double cross trispecific hybrid between Pennisetum americanum, P. purpureum, and P. squamulatum were tested for resistance to kanamycin, hygromycin, and methotrexate for use in transformation studies. All cultures showed high natural levels of resistance to kanamycin, in excess of 800 milligrams per liter, and variable levels of resistance to hygromycin. Methotrexate was a potent growth inhibitor at low concentrations with all species. Kanamycin and hygromycin were growth inhibitory only if added early (within 5 days after protoplast isolation and culture). Protoplasts of T. monococcum, P. maximum, S. officinarum, and the tri-specific hybrid were electroporated with plasmid DNA containing hygromycin (pMON410), kanamycin (pMON273), or methotrexate (pMON806) resistance genes. Resistant colonies were obtained at low frequencies (1 × 10−5 to 2 × 10−6) when selected under conditions which were growth inhibitory to protoplasts electroporated without DNA. Southern blot hybridization confirmed stable integration of plasmid DNA into T. monococcum using hygromycin vectors and P. maximum using the methotrexate vector with 1 to 10 copies integrated per haploid genome. 相似文献
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Tatiana I. Gerasimova Yurii V. Ilyin Lev J. Mizrokhi Liliya V. Semjonova Georgii P. Georgiev 《Molecular & general genetics : MGG》1984,193(3):488-492
Summary A family of unstable mutations at the cut locus in Drosophila melanogaster was obtained under the conditions of hybrid dysgenesis (Gerasimova 1981, 1982). The in situ hybridization experiments have shown that, in the original unstable ct
MR2 mutation, the 7B region of the X chromosome (where cut is located) contains a mobile dispersed genetic element, mdg4. All other unstable ct mutations derived from ct
MR2 including visible and lethal alleles and unstable ct
+ reversions, also contain mdg4 in the 7B region. The X chromosomes of the parent strain (wild type) do not contain mdg4 at all. All stable revertants derived from ct
MR2, from other unstable ct mutations, or from ct lethals lost mdg4 from the 7B region. The ct
MR2 X chromosome does not contain P-elements, although a few copies are present in the autosomes. The instability of the ct
MR2./ct
MR2 strain remained at a high level for 50 generations (1.5 years) and then rapidly decreased. A new cross with an MRh12/Cy strain (originally used for dysgenesis induction and containing a number of P-elements) increased the instability to a level exceeding the original one. The data strongly suggest that unstable ct mutations in our system are induced by transpositions of mdg4, possibly activated by P-elements. 相似文献
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