Cloning And Functional Analysis Of Inflorescence Meristem-Specific Expressed Genes In Rice (Orysa Sativa. L.)

In rice, the floral transition occurs when the vegetative shoot apical meristem converts to the inflorescence meristem. According to the result of SSH, six inflorescence meristem-specific expressed genes in rice was obtained by the method of rapid amplification of cDNA ends. EMBRYONIC FLOWER 2 gene play a major role in maintains vegetative development by repressing embryonic and flowering programs. The full-length cDNA of 0sEMF2 was 1899 bp and contained an 1872bp open reading frame (ORF) encoding a 624 amino acid protein. Sequence alignment shows that there is a homology between the deduced amino acid sequence of 0sEMF2 and EMF2 in Zea ways (60%). No late-flowering phenotype was observed in the sense transformants Enhancement of only EMF2 expression might be insufficient to repress the reproductive program in rice development. Origin recognition complex (ORC) governs the initiation site of DNA replication and formation of the prereplication complex. The full-length cDNA contained an 1140bp open reading frame encoding a 379 amino acid polypeptide. Sequence alignment shows that there is a high homology between the deduced amino sequence of 0s0RC2 and maize 0RC2 (85%). The tissue-specific expression pattern of OsORC2 reveals that it is abundant in roots, seedling and inflorescence meristem, while its expression level is much lower in mature leaves and shoot. The FK506-binding proteins (FKBPs) belong to the peptidyl prolyl cis-trans isomerase (PPIase) family, and catalyse the rotation of the peptide bond preceding a proline. 0sFKBP66contained a 1758bp open reading frame encoding a 585 amino acid polypeptide. Sequence alignment shows that there is a high homology between the deduced amino sequence of OsFKBP66 and wheat FKBP66 (79%). The heat shock expression suggested that heat shock significantly increased the accumulation of the 0sFKBP66 transcript .The tissue-specific expression pattern of 0sFKBP66 reveals that it is abundant in inflorescence meristem and seed, while its expression level is much lower in shoot, seedling, root and mature leaves. Cytochrome p450 are membrane-bound hemoproteins that are involved in a variety of oxidative reactions. CYP81B contained a 1599bp open reading frame encoding a 533 amino acid polypeptide. Sequence alignment shows that there is a homology between the deduced amino sequence of CYP81B and CYP81B1(43%). The tissue-specific expression pattern of CYP81B reveals that it is abundant in inflorescence meristem and mature leaves, while its expression level is much lower in stem, seedling, root and seed.Among the known functions for leucine-rich repeat receptor-like kinases are several significant physiological roles including disease resistance; plant growth and development and self-incompatibility. According the result of previous QTL experiment, Oryza rufipogon putative leucine-rich repeatreceptor-like kinase cluster 50Kb was sequenced. Two leucine-rich repeat receptor-like kinases were cloned by RT-PCR. Intraspecies variation analysis reveals that Expression of OsLnlk2 existed in Indica type rice, while it was not exist in japonica rice. The tissue-related expression pattern of OsLnlk2 shows that the mRNA level was extensively high in stem and immature seed, while it was much lower in leaf and root. The result of southern blot analysis indicating the OsLnlk2 belongs to a multi-copy gene family.