CLE4 peptide hormone regulatesde novoshoot regeneration in potato

Background De novo shoot regeneration involves reconstitution of stem cells under control of stem cell regulators. The WUSCHEL (WUS) transcription factor acts as a master regulator of de novo shoot regeneration controlling genotype-dependent regeneration efficiency. Previously we found that potato plants overexpressing the StCLE4 gene encoding Solanum tuberosum CLAVATA3/EMBRYO SURROUNDING REGION-RELATED peptide hormone exhibited a wus -like phenotype with inhibited growth of the shoot apical meristem. We hypothesized that StCLE4 could also modulate de novo shoot regeneration. Methods and results In this study the role of the StCLE4 peptide in de novo shoot regeneration was studied by CRISPR/Cas9 mutant analysis, evaluation of overexpression effects and gene expression analysis. We found that cle4 mutation enhanced shoot regeneration in potato. Conclusions We have found a gene in potato, the loss of which can lead to increased shoot formation. These results can be used to improve the efficiency of shoot regeneration in potato.