Abstract: This work is to reveal the roles of MeTPP1 gene in abiotic stresses such as drought and cold in cassava. Homology-based cloning method was used to clone MeTPP1 gene from cassava leaves,MEGA software to construct its neighbor-joining phylogenetic tree,DnaSP software to analyze its structural variations,and quantitative RT-PCR（qRT-PCR）to explore its expression characteristics under different abiotic treatments. The results showed that gene,MeTPP1 had a 1 131 bp open reading frame encoding 376 amino acids,and contained a conserved domain of TPP gene family. Phylogenetic analysis revealed that MeTPP1 had close genetic relationship to its homologues from Populus trichocarpa and Salix purpurea,and the sequence similarity was 77.8% and 74.5%,respectively. Genetic structural variation showed that a total of nine mis-sense mutations,which might be related to the expression of MeTPP1,were identified between cassava wild and cultivated species. qRT-PCR analysis demonstrated that the expression of MeTPP1 significantly changed in response to drought,cold,and ABA treatments. Together,these results indicate that MeTPP1 is involved in ABA-mediated drought and cold stresses of cassava at the transcriptional level,and can be served as a candidate to further study its functions in resistance of abiotic stress in cassava.

Key words: trehalose-6-phosphate, phosphatase,MeTPP1,drought,cold,expression, analysis