Cloning and Expression Analysis of SlAGO7 in Tomato
Based on EST sequences from tomato genome database(SGN),the full-length cDNA and genomic DNA sequence of SlAGO7 were isolated by using RACE and PCR.Bioinformatics methods were used to analyze the sequence characteristics of this gene and the Real-time PCR method was used to investigate the temporal and spatial expression pattern of SlAGO7 gene.These results showed that the cloned full-length cDNA of SlAGO7 was 3 238 bp in length(Genbank:JX467714),containing a 3 003 bp open reading frame(ORF)which encoding 1 000 amino acids.In addition,the full length of genomic DNA contained three extrons and two introns.The deduced SlAGO7 protein with two conserved PAZ and PIWI domains had the typical characteristics of the AGO family.This deduced amino acid had a high identity with the known AGO7 protein.Phylogenetic analysis showed that SlAGO7 was classified into the ZIPPY/AGO7 subfamily of the AGO family.Real-time PCR analysis indicated that the expression of the SlAGO7 gene was detected in vegetative tissues such as roots and stems,but not in leaves.SlAGO7 gene was mainly expressed in flower organs(Buds and flowers),while its mRNA was not detected in fruits.Therefore,SlAGO7 was probably involved in the development of flower organ in tomato.The results would provide a foundation for further dissection of the molecular and genetics mechanisms of SlAGO7 in the control of floral organ development by the ta-siRNA pathway.