Plant primary meristems: shared functions and regulatory mechanisms.

Primary plant meristems are the shoot and root meristems that are initiated at opposite poles of the plant embryo. They contain stem cells, which remain undifferentiated, and supply new cells for growth and the formation of tissues. The maintenance of a long-lasting stem cell population in meristems is achieved by signal exchange between organizing regions and the stem cells, and also by feedback signals emanating from differentiating cells. Related peptide signals that make use of different receptor classes were found to control the stem cell populations in both meristem types by regulating evolutionarily conserved homeodomain transcription factors. The precise interplay of auxin and cytokinin signaling pathways is central to keep cells in the meristem, or direct them toward differentiation.

Stahl Y ，Simon R 《-》

Conserved factors regulate signalling in Arabidopsis thaliana shoot and root stem cell organizers.

Sarkar AK ，Luijten M ，Miyashima S ，Lenhard M ，Hashimoto T ，Nakajima K ，Scheres B ，Heidstra R ，Laux T ... -  《-》

The molecular basis of cytokinin function.

Cytokinins are a class of phytohormones that regulate a wide variety of physiological and developmental processes such as shoot and root growth. Cytokinin signaling relies on a phosphorelay mechanism similar to the prokaryotic two-component system. Although the principal components mediating this cascade have been identified, only recently have we begun to understand the molecular basis of cytokinin action. For example cytokinins control cell differentiation rate during root meristem development by suppressing both auxin signaling and transport, whereas at early stages of embryo development auxin counteracts cytokinin signaling to establish the embryonic root stem-cell niche. The antagonistic interaction between cytokinins and auxin seems to also occur in other developmental processes, such as lateral root emergence and leaf initiation.

Perilli S ，Moubayidin L ，Sabatini S 《-》

A genetic framework for the control of cell division and differentiation in the root meristem.

Dello Ioio R ，Nakamura K ，Moubayidin L ，Perilli S ，Taniguchi M ，Morita MT ，Aoyama T ，Costantino P ，Sabatini S ... -  《-》

Cytokinins determine Arabidopsis root-meristem size by controlling cell differentiation.

Dello Ioio R ，Linhares FS ，Scacchi E ，Casamitjana-Martinez E ，Heidstra R ，Costantino P ，Sabatini S ... -  《CURRENT BIOLOGY》