Skip to main content
. 2002 May;14(5):969–977. doi: 10.1105/tpc.002196

Figure 5.

Figure 5.

Model of CLV3 Localization and Action.

The Arabidopsis SAM consists of three clonally distinct cell layers. The L1 epidermal layer and the L2 subepidermal layer are each single cell layers (outlined in green), whereas the interior L3 cells make up the bulk of the meristem (cells outlined in red). CLV3 is expressed at the apex of the SAM, predominantly in the superficial L1 and L2 cell layers and in a few cells of the L3. CLV1, which encodes a receptor for CLV3, is expressed in the underlying L3 cell layers. CLV3 is localized to the extracellular space and is predicted to travel through the apoplast from the L1 and L2 to the CLV1-expressing cells in the L3, which are isolated symplastically from the tunica (L1 and L2). Signaling by CLV3 through the CLV1 receptor complex causes the downregulation of WUS, restricting the WUS expression domain to the interior cells of the meristem.