GENOME-WIDE IDENTIFICATION AND CHARACTERIZATION OF THE SBP GENE FAMILY IN EUCALYPTUS GRANDIS

SQUAMOSA promoter binding proteins (SBP) are a group of plant transcription factor (TF) families that play an important role in plant development and defence response. Genome-wide investigations of SBP genes have been carried out in many plant species, however this is the first comprehensive report on the identification and characterization of SBP genes in Eucalyptus grandis (E. grandis). According to the results herein, 16 SBP genes from E. grandis were identified and SBP proteins were clustered in eight clades. 16 SBP genes were presented to distribute 7 out of 11 chromosomes and three segmental duplicated gene couple were found throughout the entire genome of E. grandis. A total of 15 conserved motifs were described and 3 out of 15 were found to be conserved among all Egrandis_SBP proteins, due to forming of SBP domain which is essential for the function of SBP proteins. Gene structures of all Egrandis_SBP genes were investigated and the estimated number of exons among all genes extended from 2 to 11. According to the synteny analysis, it was seen that homologs of E. grandis genes were found in corresponding syntenic blocks of Arabidopsis thaliana and Vitis vinifera. Digital gene expression analyses showed that most of the Egrandis_SBP genes were highly expressed in shoot tips, young leaf, xylem, mature leaf, immature xylem and phloem tissues of E. grandis. Taken all together, the results of this study will provide an important source for literature and further works.