A novel DUF740 gene family member ( OsSRDP ) from rice imparts better
climate resilience through multiple stress tolerance
Abstract
Domain of Unknown Function 740 (DUF740) is a gene family that has not
been functionally elucidated in rice, until now. We investigated the
function of rice DUF740 gene family member, LOC_Os04g59420 (
OsSRDP- O ryza s
ativa Stress Responsive DUF740
Protein) which showed upregulation in response to drought
stress in the available global expression data. Transgenic plants of
OsSRDP gene, driven by a stress-inducible promoter
AtRd29A, were developed in the background of a drought stress
sensitive rice cv. Pusa Sugandh 2 (PS2) and their transgene integration
and copy number were confirmed by molecular analysis. Homozygous
transformants showed better resilience than PS2 when subjected to
drought, salinity and cold stresses but not heat stress. Transgenic
plants maintained higher RWC, photosynthetic pigments and proline
accumulation under drought and salinity stresses. Further, they
exhibited less accumulation of reactive oxygen species (ROS) than PS2
under drought stress as seen from the transcript abundance studies of
the ROS genes. Under cold stress, OsSRDP transgenic lines
illustrated minimal cell membrane injury than PS2. Additionally, the
transgenic plants showed resistance to virulent strain of rice blast
fungus Magnaporthe oryzae. Altogether, our findings established
that stress-inducible expression of OsSRDP can significantly
enhance tolerance to multiple abiotic stresses and a biotic stress.