title: GSL2 over-expression confers resistance to Pectobacterium atrosepticum in potato.
abstract: Over-expression of the potato Gibberellin Stimulated-Like 2 ( GSL2 ) gene in transgenic potato confers resistance to blackleg disease incited by Pectobacterium atrosepticum and confirms a role for GSL2 in plant defence. The Gibberellin Stimulated-Like 2 (GSL2) gene (also known as Snakin 2) encodes a cysteine-rich, low-molecular weight antimicrobial peptide produced in potato plants. This protein is thought to play important roles in the innate defence against invading microbes. Over-expression of the GSL2 gene in potato (cultivar Iwa) was achieved using Agrobacterium-mediated gene transfer of a plant expression vector with the potato GSL2 gene under the regulatory control elements of the potato light-inducible Lhca3 gene. The resulting plants were confirmed as being transgenic by PCR, and subsequently analysed for transcriptional expression of the Lhca3-GSL2-Lhca3 chimeric potato gene. Quantitative RT-PCR analysis demonstrated that the majority of the transgenic potato lines over-expressed the GSL2 gene at the mRNA level. Based on qRT-PCR results and evaluation of phenotypic appearance, eight lines were selected for further characterisation and evaluated in bioassays for resistance to Pectobacterium atrosepticum (formerly Erwinia carotovora subsp. atroseptica), the causal agent of blackleg in potato. Three independent pathogenicity bioassays showed that transgenic lines with significantly increased transcriptional expression of the GSL2 gene exhibit resistance to blackleg disease. This establishes a functional role for GSL2 in plant defence against pathogens in potato.
authors.affiliation: The New Zealand Institute for Plant & Food Research Ltd, Private Bag 4704, Christchurch, 8140, New Zealand.
authors.forename: Sara
authors.initials: S
authors.lastname: Mohan
authors.forename: Sathiyamoorthy
authors.initials: S
authors.lastname: Meiyalaghan
authors.forename: Julie M
authors.initials: JM
authors.lastname: Latimer
authors.forename: Michelle L
authors.initials: ML
authors.lastname: Gatehouse
authors.forename: Katrina S
authors.initials: KS
authors.lastname: Monaghan
authors.forename: Bhanupratap R
authors.initials: BR
authors.lastname: Vanga
authors.forename: Andrew R
authors.initials: AR
authors.lastname: Pitman
authors.forename: E Eirian
authors.initials: EE
authors.lastname: Jones
authors.forename: Anthony J
authors.initials: AJ
authors.lastname: Conner
authors.forename: Jeanne M E
authors.initials: JM
authors.lastname: Jacobs
mesh_terms: D018744:DNA, Plant / Q000235:genetics; D060467:Disease Resistance / Q000235:genetics*; D017343:Genes, Plant; D044043:Pectobacterium; D010935:Plant Diseases / Q000382:microbiology; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism; D011198:Solanum tuberosum / Q000235:genetics* / Q000382:microbiology
chemical_list: D018744:DNA, Plant; D010940:Plant Proteins