In collaboration with:

• Italian National Agency for New technologies, Energy and Environment (ENEA).
  ENEA-Casaccia RC, BAS BIOTEC-GEN
  Via Anguillarese, 301
  00123 Rome
  Italy

Website : http://www.enea.it/com/ingl/default.htm

Laboratory Leader: Dr. P. Galeffi
Principal Researcher: Dr. A. Latini

Abstract

The Triticum durum Dehydration Responsive Factor 1 gene, TdDRF1, belonging to the DREB gene family, is expressed in response to dehydration and encodes for abiotic stress responsive transcription factors that impart stress endurance to the plants (Latini et al. 2007). Recently, the expression profile of this gene was finely examined in several wheat varieties in both greenhouse and in field conditions, during a water stress time-course (Latini et al. 2008). All obtained data spotlighted that the targeting of this gene could help the selection of cultivars for improving plant tolerance to drought.

The fine mapping of this gene, determining the exact locus position on chromosomes will be very interesting and useful. Actually, it is already established that homeologous loci of this gene exist in 1A, 1B chromosomes of durum wheat and 1A, 1B and 1D chromosomes of bread wheat; in addiction, there are some evidences about the existence of some paralogous gene copies and also pseudogenes without introns.

The collaboration with the CNRGV is highly fruitful, because it holds the most relevant BAC genomic DNA collections of wheat. In addiction to several collections of bread wheat, at CNRGV, durum wheat (Cenci et al. 2003) and chromosome-specific (such as 1D, 4D, 6D and 1AS or 1AL of hexaploid wheat – Janda et al. 2004) genomic BAC libraries are also available.

Actually, the bread wheat Chinese Spring BAC library (Tae-B-CS) was screened by both PCR on pools and microarray hybridization techniques with primers specific for the TdDRF1 sequence. A durum wheat library is still under screening. Several clones containing the target sequence were identified and are being characterized by restriction analyses, chromosome walking and complete BAC sequencing.

From the positive BAC clones, the upstream and downstream TdDRF1 gene regions will be sequenced, allowing the identification of the promoter and other regulatory sequences (enhancers, alternative splicing signals, and so on). Furthermore, the complete sequence of a selected BAC clone will reveal if some other dehydration-responsive gene is located next to the target locus and this information will be precious for developing applications in molecular assisted breeding programs aimed to the release of drought tolerant wheat cultivars.

- Latini A, Rasi C, Sperandei M, Cantale C, Iannetta M, Dettori M, Ammar K, Galeffi P: Identification of a DREB-related gene in Triticum durum and its expression under water stress conditions. Annals of Applied Biology (2007), 150: 187-195.
- Latini A, Sperandei M, Sharma S, Cantale C, Iannetta M, Dettori M, Ammar K, Galeffi P: Molecular analyses of a dehydration-related gene from the DREB family in durum wheat and triticale. In Biosaline Agriculture and High Salinity Tolerance. Published by Birkhäuser and Verlag. Edited by Abdelly C, Öztürk M, Ashraf M, Grignon C. (2008), 286-295.
- Cenci a, Chantret N, Kong X, Gu Y, Anderson OD, Fahima T, Distelfeld, Dubcovsky J: Construction and characterization of a half million clone BAC library of durum wheat (Triticum turgidum ssp. durum). Theoretical and Applied Genetics (2003), 107: 931-939.
- Janda J, Bartoš J, Šafář J, Kubaláková M, Valárik M, Čihalíková J, Šimková H, Caboche M, Sourdille P, Bernard M, Chalhoumb B, Doležel J: Construction of a subgenomic BAC library specific for chromosomes 1D, 4D and 6D of Hexaploid wheat. Theoretical and Applied Genetics (2004) 109: 1337-1345.

This collaboration was also supported by a COST-STSM-FA0604 grant, given to A. Latini.

CNRGV involvement

Responsible : Elisa PRAT/ Sonia VAUTRIN

- Macroarray production/ screening
- 2D DNA pools screening