UC San Diego

In Arabidopsis thaliana the majority of the fruit comprises an ovary with three primary tissue regions; the valve, the valve margin and the replum. Interestingly, there exists active cell proliferation in the replum domain, which leads to the formation of specialized structures located inside of the ovary, including the ovules. This feature makes the replum tissue to be considered one of the "quasi-meristem" structures present in the Arabidopsis thaliana fruit. A set of regulatory genes has been identified to control different aspects of replum development and growth, including the replum identity genes RPL and BP. However, keeping in mind the meristem-like features that the replum has we wanted to explore whether additional meristem-related genes are also impinging upon replum formation. We have uncovered an additional player participating in replum morphopgenesis, which, interestingly, is post-transcriptionally regulated by small RNAs. A comprehensive and detailed analysis of this novel factor in the context of replum development, as well as the importance of its regulation by small RNA in this developmental process are the main focuses of this work