Initial Characterization and Expression Pattern Analysis of Tobacco (Nicotiana Tabacum) Sucrose Synthase Gene

The complete mRNA sequence of one tobacco (nicotiana tabacum) gene—guanosine monophosphate (GMP)synthase, was amplified using the rapid amplification of cDNA ends methods. The full-length tobacco GMP synthase gene mRNA was 2,127bp containing a 1,617 bp open reading frame, which encodes a protein of 538 amino acids. Sequence analysis revealed that the GMP synthase of tobacco shares high homology with the GMP synthase of wood tobacco(99%), nicotiana attenuata(99%), nicotiana tomentosiformis(99%), potato(92%), Lycopersicon pennellii(92%), lycopersicon esculentum(92%), capsicum annuum(91%), capsicum chinense(91%) and capsicum baccatum(90%). BLAST analysis within the tobacco high throughout genomic sequences database revealed that this gene has 5 introns and 6 exons. Results also showed that tobacco GMP synthase gene has a closer genetic relationship with the GMP synthase gene of wood tobacco. Tissue expression profile analysis revealed that the tobacco GMP synthase gene was highly expressed in leaf, but moderately expressed in root, flower and stem. Our experiment established the foundation for further research on this tobacco gene.