Synthase Gene from Ricinus communis L

1 L-myo-Inositol-1-phosphate synthase (EC 5.5.1.4, MIPS), an evolutionarily conserved enzyme protein, catalyzes the conversion of D-glucose-6-phosphate into 1 L-myo-inositol-1-phosphate (MIP), which is the fi rst and rate-limiting step in the biosynthesis of all inositol-containing compounds (Ray Chaudhuri et al., 1997; Abid et al., 2009). MIPS is found in diverse organisms, both eukaryotic and prokaryotic, suggesting that the pathway for 1 L-myo-inositol-1-phosphate from D-glucose-6-phosphate arose early in the evolution of life. The properties and generally accepted catalytic mechanisms of the enzyme are similar in all organisms where such assessment has been undertaken (Bachhawat and Mande, 2000). MIPS-encoding sequences represent multi-gene families in some plant species. The multiple MIPS genes in plant species may be applied to attune its differential expression to specifi c physiological functions (Abid et al., 2009). MIPS-coding sequences have been isolated and characterized from a number of plant species, such as chickpea (Kaur et al., 2008), Arabidopsis (Johnson and Sussex, 1995), Phaseolus vulgaris (Johnson and Wang, 1996), and Sesamum indicum (Chun et al., 2003). Recently, some experimental data have demonstrated that the expression levels of the MIPS gene might be up-regulated and the MIPS activity increased when plants were exposed to strong light treatment and salinity stress as well (Ray Chaudhuri and Majumder, 1996; Ishitani et al., 1996; Chun et al., 2003). In addition, studies of MIPS in Arabidopsis and Glycine max using an RNAi approach revealed the critical role of the MIPS genes in early seed development through the regulation of endosperm formation (Nunes et al., 2006; Chiera and Grabau, 2007; Mitsuhashi et al., 2008). Although MIPS has been characterized in some plant species, identifi cation of its gene and function is still to come. Ricinus communis L., belonging to the Euphorbiaceae family, is widely distributed in tropical and partially in subtropical areas. Various parts of the plant hold potential for the use as a source of lubricating oil and chemical materials (Sujatha et al., 2008). As shown by a previous review of the literature, little information concerning the MIPS gene and its transcription level in R. communis L. under drought stress is available. In the present study, a MIPS cDNA from R. communis L. was Cloning and Expression Analysis of 1 L-myo-Inositol-1-phosphate Synthase Gene from Ricinus communis L.