title: Identification and functional validation of a unique set of drought induced genes preferentially expressed in response to gradual water stress in peanut.
abstract: Peanut, found to be relatively drought tolerant crop, has been the choice of study to characterize the genes expressed under gradual water deficit stress. Nearly 700 genes were identified to be enriched in subtractive cDNA library from gradual process of drought stress adaptation. Further, expression of the drought inducible genes related to various signaling components and gene sets involved in protecting cellular function has been described based on dot blot experiments. Fifty genes (25 regulators and 25 functional related genes) selected based on dot blot experiments were tested for their stress responsiveness using northern blot analysis and confirmed their nature of differential regulation under different field capacity of drought stress treatments. ESTs generated from this subtracted cDNA library offered a rich source of stress-related genes including signaling components. Additional 50% uncharacterized sequences are noteworthy. Insights gained from this study would provide the foundation for further studies to understand the question of how peanut plants are able to adapt to naturally occurring harsh drought conditions. At present functional validation cannot be deemed in peanut, hence as a proof of concept seven orthologues of drought induced genes of peanut have been silenced in heterologous N. benthamiana system, using virus induced gene silencing method. These results point out the functional importance for HSP70 gene and key regulators such as Jumonji in drought stress response.
authors.affiliation: Department of Crop Physiology, University of Agricultural Sciences, GKVK, Bangalore, 560 065, Karnataka, India. ggovind@ice.mpg.de
authors.forename: Geetha
authors.initials: G
authors.lastname: Govind
authors.forename: Vokkaliga ThammeGowda
authors.initials: VT
authors.lastname: Harshavardhan
authors.forename: Harshavardhan Vokkaliga
authors.initials: HV
authors.lastname: ThammeGowda
authors.forename: Jayaker Kalaiarasi
authors.initials: JK
authors.lastname: Patricia
authors.forename: Patricia Jayaker
authors.initials: PJ
authors.lastname: Kalaiarasi
authors.forename: Ramachandra
authors.initials: R
authors.lastname: Dhanalakshmi
authors.forename: Dhanalakshmi Ramchandra
authors.initials: DR
authors.lastname: Iyer
authors.forename: Muthappa
authors.initials: M
authors.lastname: Senthil Kumar
authors.forename: Senthil Kumar
authors.initials: SK
authors.lastname: Muthappa
authors.forename: Nese
authors.initials: N
authors.lastname: Sreenivasulu
authors.forename: Sreenivasulu
authors.initials: S
authors.lastname: Nese
authors.forename: Makarla
authors.initials: M
authors.lastname: Udayakumar
authors.forename: Udaya Kumar
authors.initials: UK
authors.lastname: Makarla
mesh_terms: D010367:Arachis / Q000235:genetics* / Q000502:physiology*; D001483:Base Sequence; D002734:Chlorophyll / Q000378:metabolism; D004247:DNA / Q000378:metabolism; D018076:DNA, Complementary / Q000378:metabolism; D003681:Dehydration; D055864:Droughts; D020224:Expressed Sequence Tags; D015723:Gene Library; D020868:Gene Silencing; D017343:Genes, Plant; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics; D008969:Molecular Sequence Data; D018515:Plant Leaves / Q000378:metabolism; D014026:Nicotiana / Q000235:genetics
chemical_list: D018076:DNA, Complementary; D018840:HSP70 Heat-Shock Proteins; D002734:Chlorophyll; D004247:DNA