Symplastic communication spatially directs local auxin biosynthesis to maintain root stem cell niche in Arabidopsis ($)

Although plant cells are surrounded by walls, cytoplasmic strands connect adjacent cells through junctions called plasmodesmata. Liu et al. investigated the contributions of plasmodesmata to signaling between root quiescent center (QC) cells and the cells that surround the QC by expression of an inducible gene for callose production in the QC cells. Callose is a polysaccharide that blocks plasmodesmata and is usually produced following wounding or infection to prevent the spread of pathogens or damage. The authors show that blocking symplastic communication disrupted auxin biosynthesis, formation of an auxin gradient, and stem cell maintenance. Proc. Natl. Acad. Sci. USA 10.1073/pnas.1616387114