Assessment of miR156 and miR172 expression level in Ilex paraguariensis leaves

DUARTE, MARÍA J.; ACEVEDO, RAÚL M.; SANSBERRO, PEDRO A.

Santa Fé

Congreso; RAFV Conference 2021. XXXIII Argentinian meeting of Plant Physiology; 2022

Sociedad Argentina de Fisiología Vegetal

Currently, the genetic improvement of yerba mate based on the selection of elite genotypes is limited due to the impossibility to propagate adult plants. In general, woody species lose the competence to form adventitious roots as they progress from the juvenile to the adult vegetative phase. Recent studies suggest that miR156 and miR172 participate in the regulation of the ageing process. Therefore, to compare the miRNA expression levels between genotypes at different vegetative phases, it is necessary to verify that their expression is stable among plants in the same phase. To determine whether miRNAs quantitative expression is affected by leaf position, total RNA was isolated from the 3rd, 7th, 12th, and last leaf (counting from the shoot apical meristem) from plants of similar ages obtained by macropropagation. Three different protocols using stem-loop primers were evaluated to reverse transcribe mature miRNAs 156 and 172 into cDNA. Then, real-time PCR with the SYBR green method was employed to quantify their expression level. The results obtained suggest that the method described by Varkonyi-Gasic et al. is the most effective for yerba mate leaves, getting the older leaf on the stem the most stable expression of miR156 and miR172.