Abstract:In order to understand the evolutionary characteristics of miR172 family members and their expression in different tissues, we explored miR172 family members of Chinese kale in this study. The evolution characteristics of miR172s and their expression patterns in different tissues were analyzed. The results showed that:(1) there were 20 miR172 members in Chinese kale. By comparison, all 20 sequences have an overlapping region, in which 8 bases of ACTAGATC are highly conserved. (2)The results of mfold prediction showed that folding free energy of five precursor components of miR172a family ranges from -54.55 kal/mol to -78.60 kal/mol, both of which could spontaneously form a typical and stable stemloop secondary structure. (3) Phylogenetic tree shows that the miR172 in Chinese kale is closely related to Carica papaya miR172. (4) A total of 13 different genes were predicted to be targets of miR172a in Chinse kale and multiple members could also target the same gene. (5)The expression of different members of premiR172a and premiR172b was significantly different in different tissues. The premiR172a1, premiR172a2, premiR172a3 and premiR172b were highly expressed in pods of Chinese kale and the premiR172b5p and premiR172b5p2 were highly expressed in flowers, indicating that miR172 plays an important role in the development of Chinese kale flowers and pods.