Conserved factors regulate signalling in Arabidopsis thaliana shoot and root stem cell organizers.
Throughout the lifespan of a plant, which in some cases can last more than one thousand years, the stem cell niches in the root and shoot apical meristems provide cells for the formation of complete root and shoot systems, respectively. Both niches are superficially different and it has remained unclear whether common regulatory mechanisms exist. Here we address whether root and shoot meristems use related factors for stem cell maintenance. In the root niche the quiescent centre cells, surrounded by the stem cells, express the homeobox gene WOX5 (WUSCHEL-RELATED HOMEOBOX 5), a homologue of the WUSCHEL (WUS) gene that non-cell-autonomously maintains stem cells in the shoot meristem. Loss of WOX5 function in the root meristem stem cell niche causes terminal differentiation in distal stem cells and, redundantly with other regulators, also provokes differentiation of the proximal meristem. Conversely, gain of WOX5 function blocks differentiation of distal stem cell descendents that normally differentiate. Importantly, both WOX5 and WUS maintain stem cells in either a root or shoot context. Together, our data indicate that stem cell maintenance signalling in both meristems employs related regulators.
Sarkar
Ananda K
AK
Institute of Biology III, University of Freiburg, Schänzlestrasse 1, 79104 Freiburg, Germany.
Luijten
Marijn
M
Miyashima
Shunsuke
S
Lenhard
Michael
M
Hashimoto
Takashi
T
Nakajima
Keiji
K
Scheres
Ben
B
Heidstra
Renze
R
Laux
Thomas
T
D017360:Arabidopsis / Q000033:anatomy & histology / Q000166:cytology / Q000378:metabolism*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D002454:Cell Differentiation; D017124:Conserved Sequence; D035264:Flowers / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism*; D007210:Indoleacetic Acids / Q000378:metabolism; D018519:Meristem / Q000166:cytology / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation / Q000235:genetics; D018517:Plant Roots / Q000166:cytology* / Q000378:metabolism; D018520:Plant Shoots / Q000166:cytology* / Q000378:metabolism; D015398:Signal Transduction; D013234:Stem Cells / Q000166:cytology* / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism
D029681:Arabidopsis Proteins; D018398:Homeodomain Proteins; D007210:Indoleacetic Acids; C100978:SCR protein, Arabidopsis; C410510:SHORT ROOT protein, Arabidopsis; D014157:Transcription Factors; C116421:WUSCHEL protein, Arabidopsis