Principal investigator:

Timmermans, Marja, Prof. Dr.,
Zentrum für Molekularbiologie der Pflanzen (ZMBP)

Abteilung Entwicklungsgenetik und Zellbiologie

Auf der Morgenstelle 32

72076 Tübingen

Phone: 49 7071 29 78099

E-mail: marja.timmermansspam prevention@zmbp.uni-tuebingen.de

Summary:

Development of multicellular organisms depends on intercellular communication via mobile signals that provide positional information to coordinate cell fate decisions. In addition to peptide ligands, transcription factors, and hormones, plants use small RNAs as instructive positional cues. One obvious advantage of employing mobile small RNAs in development is that they represent a distinct class of signaling molecules whose movement can, in principle, be regulated independently from that of other mobile signals. However, while it is known that small RNAs can move symplastically via plasmodesmata, major questions regarding intercellular small RNA mobility remain: how do small RNAs move, via passive diffusion or facilitated transport, as free molecules or as part of a protein complex, is mobility a basic feature of all cells or carefully regulated during development? Our preliminary data indicates that miRNA mobility is dynamically regulated during development, and that even though both proteins and small RNAs move from cell to cell via plasmodesmata, distinct regulatory mechanisms control this mobility. The proposed project seeks to understand how this specificity is generated, and what the underlying molecular mechanisms are. This information will allow us to arrive at a comprehensive understanding of small RNAs as mobile instructive cues, which will be essential to understand the interplay of signals that coordinate the many patterning processes occurring in close spatial and temporal vicinity within plant stem cell niches.