SOL1 and SOL2 regulate fate transition and cell division in stomatal lineage ($) (Development)

Stomata and pavement cell development in the leaves occur through programmed asymmetric cell division. In this paper the authors demonstrated the role of two CHC domain proteins, SOL1 and SOL2 that were identified previously by the same group to be downstream targets of a bHLH transcriptional factor SPEECHLESS. The two genes are close homologs of TSO1 which is known to play crucial role in floral meristem maintenance. SOL1 is expressed in the early stages of stomatal lineage cells ahead of cell division and SOL2 in the meristemoid and GMC as illustrated by co-expression with lineage specific markers. The double loss of function mutant sol1sol2 causes development of stomatal pairs and increased small cell phenotype which is rescued by gene complementation. Together these results showed the function of two important components in stomatal development. (Summary by Suresh Damodaran) Development