Transcriptional and post-transcriptional regulation of the miR171-LaSCL6module during somatic embryogenesis inLarix kaempferi

Key message Expression analysis ofLarix kaempferimature miR171s and their primary transcripts and target geneLaSCL6during somatic embryogenesis revealed the transcriptional and post-transcriptional regulation of the miR171-LaSCL6module. Somatic embryogenesis provides a useful experimental system for studying the regulatory mechanisms of plant development. The level and activity of microRNA171 (miR171) fluctuate during somatic embryogenesis inLarix kaempferi, but the underlying mechanisms are still unclear. Here, inL. kaempferiwe identified five members of the miR171 family, which cleaveLaSCL6mRNA at different sites. In addition, we improved the method of measuring miRNA activity in a more direct way. Furthermore, we measured the expression patterns of mature miR171s and their primary transcripts during somatic embryogenesis inL. kaempferiand found that their patterns differed, indicating that the transcription ofMIR171genes and the subsequent cleavage of their intermediate products are regulated. Taken together, our findings not only offer a means to study the regulation of miRNA activity, but also provide further insight into the regulation ofL.kaempferisomatic embryogenesis by miR171-LaSCL6.

Automated summary

The study investigated the expression and regulatory mechanisms of miR171 and its target gene LaSCL6 during somatic embryogenesis in Larix kaempferi. It identified five members of the miR171 family that cleave LaSCL6 mRNA at different sites and improved a method for measuring miRNA activity. The expression patterns of mature miR171s and their primary transcripts differed during somatic embryogenesis, indicating regulation of MIR171 gene transcription and cleavage of intermediate products.