Somatic cell selection for chlorsulfuron-resistant mutants in potato: identification of point mutations in the acetohydroxyacid synthase gene

BMC Biotechnology

Research Article

Anthony J. Conner¹  Philippa J. Barrell²  Julie M. Latimer²  Michelle L. Thompson²  Samantha J. Baldwin²  Jeanne M.E. Jacobs³ 

[1] Bio-Protection Research Centre, Lincoln University, PO Box 85084, 7647, Lincoln, New Zealand;AgResearch Ltd, Lincoln Research Centre, Private Bag 4749, 8140, Christchurch, New Zealand;The New Zealand Institute for Plant & Food Research Limited, Private Bag 4704, 8140, Christchurch, New Zealand;The New Zealand Institute for Plant & Food Research Limited, Private Bag 4704, 8140, Christchurch, New Zealand;Bio-Protection Research Centre, Lincoln University, PO Box 85084, 7647, Lincoln, New Zealand;

关键词: Acetohydroxyacid synthase;    Acetolactate synthase;    Chlorsulfuron resistance;    Intragenic selectable marker;    Potato;    Somatic cell selection;    Sulfonylurea resistance;   

DOI  :  10.1186/s12896-017-0371-4

 received in 2017-03-21, accepted in 2017-06-01,  发布年份 2017

来源: Springer

【 摘 要 】

BackgroundSomatic cell selection in plants allows the recovery of spontaneous mutants from cell cultures. When coupled with the regeneration of plants it allows an effective approach for the recovery of novel traits in plants. This study undertook somatic cell selection in the potato (Solanum tuberosum L.) cultivar ‘Iwa’ using the sulfonylurea herbicide, chlorsulfuron, as a positive selection agent.ResultsFollowing 5 days’ exposure of potato cell suspension cultures to 20 μg/l chlorsulfuron, rescue selection recovered rare potato cell colonies at a frequency of approximately one event in 2.7 × 105 of plated cells. Plants that were regenerated from these cell colonies retained resistance to chlorsulfuron and two variants were confirmed to have different independent point mutations in the acetohydroxyacid synthase (AHAS) gene. One point mutation involved a transition of cytosine for thymine, which substituted the equivalent of Pro-197 to Ser-197 in the AHAS enzyme. The second point mutation involved a transversion of thymine to adenine, changing the equivalent of Trp-574 to Arg-574. The two independent point mutations recovered were assembled into a chimeric gene and binary vector for Agrobacterium-mediated transformation of wild-type ‘Iwa’ potato. This confirmed that the mutations in the AHAS gene conferred chlorsulfuron resistance in the resulting transgenic plants.ConclusionsSomatic cell selection in potato using the sulfonylurea herbicide, chlorsulfuron, recovered resistant variants attributed to mutational events in the AHAS gene. The mutant AHAS genes recovered are therefore good candidates as selectable marker genes for intragenic transformation of potato.

【 授权许可】

CC BY   
© The Author(s). 2017