The stem cell population of Arabidopsis shoot meristems in maintained by a regulatory loop between the CLAVATA and WUSCHEL genes.
The higher-plant shoot meristem is a dynamic structure whose maintenance depends on the coordination of two antagonistic processes, organ initiation and self-renewal of the stem cell population. In Arabidopsis shoot and floral meristems, the WUSCHEL (WUS) gene is required for stem cell identity, whereas the CLAVATA1, 2, and 3 (CLV) genes promote organ initiation. Our analysis of the interactions between these key regulators indicates that (1) the CLV genes repress WUS at the transcript level and that (2) WUS expression is sufficient to induce meristem cell identity and the expression of the stem cell marker CLV3. Our data suggest that the shoot meristem has properties of a self-regulatory system in which WUS/CLV interactions establish a feedback loop between the stem cells and the underlying organizing center.
Schoof
H
H
Zentrum für Molekularbiologie der Pflanzen, Tübingen, Federal Republic of Germany.
Lenhard
M
M
Haecker
A
A
Mayer
K F
KF
Jürgens
G
G
Laux
T
T
D017360:Arabidopsis / Q000166:cytology* / Q000201:enzymology / Q000235:genetics*; D029681:Arabidopsis Proteins; D015971:Gene Expression Regulation, Enzymologic; D018506:Gene Expression Regulation, Plant; D018398:Homeodomain Proteins / Q000235:genetics / Q000378:metabolism*; D017403:In Situ Hybridization; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism; D018519:Meristem / Q000201:enzymology / Q000648:ultrastructure*; D008855:Microscopy, Electron, Scanning; D016296:Mutagenesis / Q000502:physiology; D010641:Phenotype; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D017346:Protein Serine-Threonine Kinases; D012333:RNA, Messenger / Q000032:analysis; D020794:Receptor Protein-Tyrosine Kinases / Q000235:genetics / Q000378:metabolism*; D012639:Seeds / Q000166:cytology / Q000502:physiology; D019076:Transgenes / Q000502:physiology
C118167:AT2G27250 protein, Arabidopsis; D029681:Arabidopsis Proteins; C401621:CLV2 protein, Arabidopsis; D018398:Homeodomain Proteins; D008565:Membrane Proteins; D010940:Plant Proteins; D012333:RNA, Messenger; C116421:WUSCHEL protein, Arabidopsis; D020794:Receptor Protein-Tyrosine Kinases; C118166:CLV1 protein, Arabidopsis; D017346:Protein Serine-Threonine Kinases