Identification and functional validation of a unique set of drought induced genes preferentially expressed in response to gradual water stress in peanut.
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.
Govind
Geetha
G
Department of Crop Physiology, University of Agricultural Sciences, GKVK, Bangalore, 560 065, Karnataka, India. ggovind@ice.mpg.de
Harshavardhan
Vokkaliga ThammeGowda
VT
ThammeGowda
Harshavardhan Vokkaliga
HV
Patricia
Jayaker Kalaiarasi
JK
Kalaiarasi
Patricia Jayaker
PJ
Dhanalakshmi
Ramachandra
R
Iyer
Dhanalakshmi Ramchandra
DR
Senthil Kumar
Muthappa
M
Muthappa
Senthil Kumar
SK
Sreenivasulu
Nese
N
Nese
Sreenivasulu
S
Udayakumar
Makarla
M
Makarla
Udaya Kumar
UK
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
D018076:DNA, Complementary; D018840:HSP70 Heat-Shock Proteins; D002734:Chlorophyll; D004247:DNA