Genome-Wide Identification of the Argonaute Protein Family and Its Expression Analysis under PEG6000, ABA and Heat Treatments in Populus alba × P. glandulosa

The argonaute (AGO) protein, as an important member of the small RNA (sRNA) regulatory pathway gene-silencing complex (RNA-induced silencing complex, RISC), is a key protein that mediates gene and plays role in recruitment sRNAs. In this study, bioinformatics was used to identify AGO family poplar study its expression various tissues response abiotic stress treatments. A total 15 PtAGO genes were identified poplar, which unevenly distributed 9 chromosomes. Most proteins predicted be located nucleus chloroplast. PtAGOs had similar motif structures conserved motifs, except for PtAGO3. All could clustered into 3 groups, Group II, including PtAGO2/3/7, smallest number exons, while others more than 20 exons. Cis-regulatory elements involved light response, growth development, hormone-induced responses found promoters members. Further analysis tissue-specific patterns. For example, PtAGO7 PtAGO10b mainly expressed xylem might secondary development. Furthermore, tests, heat, ABA PEG treatments, showed most respond quickly treatment, multiple constantly regulated under heat-shock stress. These results provide basis elucidation mechanism further molecular breeding poplar.