Keywords: 
• sugarcane /
• B12D gene /
• bioinformatics /
• real-time PCR

Abstract: A full length cDNA sequence of sugarcane gene was obtained from sugarcane（Saccharum officinarum L.） stem full length cDNA library through large-scale sequencing and validated by the corresponding bioinformatics analysis,termed ScB12D（Genbank Accession number: KF714497）. The full length of ScB12 D gene was771 bp,with a 264 bp open reading frame（ ORF）,encoding 87 amino acids residues. The ScB12 D of sugarcane was a basic protein,which has a conserved functional domain with the main function for energy metabolism,and this protein was located in plasma membrane. The main secondary structure element was random coil.At the same time,the ScB12 D genes is conservative in different species,especially highly conservative in kindred plants. The B12 D gene in sugarcane has a homology of more than 90% with the same genes in the monocotyledonous gramineous plants of maize,millet,sorghum and rice,and around 70% with the same genes in the dicotyledonous plants of sweet potatoes and camellia. Real-time quantitative PCR（ RT-qPCR） analysis revealed that the expression of ScB12 D was higher in root and sheath than in leaf sheath,stem（contain pith and skin）,lateral buds and leaf. Moreover,after inoculation with Sporisorium scitamineum,the expression of this gene decreased in the different time points. Meanwhile,the expression of ScB12D in the NaCl stress was the highest in abiotic stresses and slightly lower under the abscisic acid stress. It can be inferred that the sugarcane B12 D gene be associated with the reaction mechanism of sugarcane to biotic and abiotic stresses.