Campus Montpellier SupAgro/INRA de La Gaillarde (2, place P. Viala Montpellier)

 Thursday Sept 20, 2018. Room to be precised

Diego M. ALMEIDA

(B&PMP- Post-doct student of TSF team)

Regulation of the OsNHX1 Gene Expression: Identification and Characterization of Novel Transcription Factors

 Soil salinity is a major environmental constraint to crop production, resulting in considerable yield losses around the globe every year. Rice, a staple food of more than half of the world’s population, like as most of the crops is very sensitive to salt. Indeed, among the most agronomically important crops, rice is the most salt sensitive. However, some degree of genotype tolerance for salt stress is available in the rice germplasm. To cope with salt stress conditions, plants evolved several and diverse response mechanisms. One of these mechanisms is tissue tolerance, in which high salt concentration is found in leaves but is compartmentalized, especially in the vacuole, reducing the deleterious effect of Na+ in the cytosol. This Na+/H+ exchange is mediated by members of a family of transporters referred to as K+,Na+/H+ antiporters (NHX-type). Among them, NHX1 is the most abundant member. Several studies have shown that NHX1 overexpression leads to improved salt and drought stress tolerance in various plant species. Given that transcription factors can act as master regulators of different cellular processes, they are promising candidates for modifying complex traits in crop plants, such as salt stress tolerance. Nevertheless, NHX1 transcriptional regulation under salt stress is poorly understood. To investigate how OsNHX1 is transcriptionally regulated in response to salt stress in a salt-tolerant rice genotype (Hasawi), a salt stress-induced cDNA expression library was constructed and subsequently screened using the yeast one-hybrid system and the OsNHX1 promoter as bait. Five transcription factors belonging to three distinct TF families: one TCP (OsPCF2), one CPP (OsCPP5) and three NIN-like (OsNIN-like2, OsNIN-like3 and OsNIN-like4) were identified as binding to OsNHX1 promoter and further characterized.

Contact :  Tou Cheu Xiong (tou-cheu.xiong@inra.fr)