Identification & Characterization
of Stress Related Genes from Local Habitat
in the North-West Coastal Region of Egypt

Much of the land of Egypt has become desertified (e.g. North-West Coastal region) due to overgrazing and collection of firewood. Because many of these areas are not being considered for cultivation, much of the present land reclamation programs are not directed toward their rehabilitation. There is a need to reclaim much of this land and restore it to greater use, particularly for grazing purposes. These lands can be rehabilitated by revegetating with perennial shrubs (e.g. Atriplex) that have excellent forage quality. Local shrub flora, which are stress-tolerant, can be used for fodder production and/or range reseeding, but it is important to understand the basis of adaptation to stressed environments. Thus, there is a need to identify and characterize stress tolerance (drought, salinity and heat shock) genes from local habitat in the North-West Coastal region of Egypt. Study of the induction and expression of these stress genes in wild plants and forage shrubs could provide understanding of how these plants adapt to the arid environment. Furthermore, it will provide information for selection of stress tolerance among different wild plant sources.

OBJECTIVES

•  Investigation and characterization of genetic diversity among wild germplasm to determine the gene pools and genetic distances between related species.

•  Stress (drought, salinity and heat-shock) cDNA clones which have been isolated from other plants will be used as hybridization probes to screen wild plants.

•  PCR specific-primers will be used for screening for stress-related sequences.

•  Isolated clones will be studied both structurally and functionally. Structural analysis includes restriction site mapping and DNA sequencing. Functional analysis involves Southern and Northern blot hybridizations.

•  In vitro expression of cloned genes in E.coli will be carried out in order to know whether these genes are biologically active.

•  Finally, biologically active genes will be subcloned into eukaryotic expression vectors for transfer to economically important crop plants.

ACHIEVEMENTS

•  The genetic diversity among different taxa representing Vicia, Pisum, Lathyrus and Astragalus species was investigated and characterized using cluster analysis based on the data from protein, isozyme and RAPD-PCR.

•  A PCR DNA fragment representing an osmotin gene from Atriplex nummularia was amplified, isolated and sequenced, which showed 70% homology with other osmotin genes.

•  Glycine aldhyde dehydrogenase gene was isolated and characterized from the halophytic plant Arthrocnemon gluacum, its expression under different salt concentrations was also studied.

•  Dehydrin gene was recently isolated, characterized and sequenced from the Egyptian wild plant Vicia monantha.