Expression of coordinately regulated defence response genes and analysis of their role in disease resistance in Medicago truncatula

Molecular Plant Pathology - Tập 12 Số 8 - Trang 786-798 - 2011
Deborah A. Samac1, Silvia Peñuela, Judy A. Schnurr, E Nicole Hunt, Dawn Foster‐Hartnett, Kathryn A. VandenBosch, J. Stephen Gantt
1USDA-ARS-Plant Science Research Unit, St. Paul, MN 55108, USA. [email protected]

Tóm tắt

SUMMARYMicroarray technology was used to identify the genes associated with disease defence responses in the model legume Medicago truncatula. Transcript profiles from M. truncatula cv. Jemalong genotype A17 leaves inoculated with Colletotrichum trifolii and Erysiphe pisi and roots infected with Phytophthora medicaginis were compared to identify the genes expressed in response to all three pathogens and genes unique to an interaction. The A17 genotype is resistant to C. trifolii and E. pisi, exhibiting a hypersensitive response after inoculation, and is moderately susceptible to P. medicaginis. Among the most strongly up‐regulated genes in all three interactions were those encoding a hevein‐like protein, thaumatin‐like protein (TLP) and members of the pathogenesis response (PR)10 family. Transcripts of genes for enzymes in the phenylpropanoid pathway leading to the production of isoflavonoid phytoalexins increased dramatically in response to inoculation with the foliar pathogens. In P. medicaginis‐inoculated roots, transcripts of genes in the phenylpropanoid pathway peaked at 5 days post‐inoculation, when symptoms became visible. Transcript accumulation of three PR10 family members, a TLP and chalcone synthase (CHS) was assessed in M. truncatula genotype R108 plants. The R108 plants are resistant to C. trifolii and moderately susceptible to E. pisi and P. medicaginis. Transcript accumulation paralleled the stages of pathogen development. To evaluate the role of a TLP, a PR10 family member and CHS in disease resistance, transgenic R108 plants containing interfering RNA (RNAi) constructs were produced. Reduced expression of PR10 and TLP had no effect on the disease phenotype, whereas reduced expression of CHS resulted in increased susceptibility to necrotrophic pathogens.

Từ khóa


Tài liệu tham khảo

10.1007/s10681-006-6767-1

10.1094/MPMI-21-1-0061

10.1023/A:1006475303115

10.1007/BF00240890

10.1007/s11103-009-9496-8

10.1007/s00425-006-0344-7

10.1007/s11103-005-0184-z

10.1007/s00425-006-0466-y

10.1016/S0065-2296(04)41001-5

10.1046/j.1364-3703.2002.00131.x

10.1016/j.plantsci.2007.08.001

10.1111/j.1364-3703.2007.00395.x

He X.Z., 2000, Genetic manipulation of isoflavones 7‐O‐methyltransferase enhances biosynthesis of 4′‐O‐methylated isoflavonoid phytoalexins and disease resistance in alfalfa, Plant Cell, 12, 1689

10.1071/FP02033

10.1007/s00122-005-1969-9

10.1016/j.plaphy.2009.05.004

10.1007/s00299-007-0485-6

10.1016/j.pmpp.2006.06.004

10.1007/s00299-010-0826-8

10.1104/pp.105.070326

10.1146/annurev.phyto.44.070505.143425

10.1016/j.pbi.2008.04.007

10.1094/MPMI-20-8-0887

10.1094/MPMI.2004.17.10.1051

10.1094/Phyto-84-283

10.1046/j.1365-313X.2003.01951.x

10.1007/BF00029598

10.1007/s10725-006-0022-6

10.1111/j.1467-7652.2006.00201.x

10.1071/FP04135

10.1094/MPMI.2004.17.8.909

10.1007/s002990050405

10.1073/pnas.091062498

10.1046/j.0931-1785.2003.00768.x

Velazhahan R., 1999, Pathogenesis‐Related Proteins in Plants, 107

10.1105/tpc.105.038232

10.1186/1471-2229-6-26

10.1094/MPMI-18-1161

Thông tin
Thông tin xuất bản

Molecular Plant Pathology

Tập 12 Số 8

786-798

Thông tin tác giả