Analysis of the transcription factor WUSCHEL and its functional homologue in Antirrhinum reveals a potential mechanism for their roles in meristem maintenance.
One of the most significant features of plant development is the way in which it can be elaborated and modulated throughout the life of the plant, an ability that is conferred by meristems. The Arabidopsis thaliana WUSCHEL gene (WUS), which encodes a homeodomain transcription factor, is required to maintain the stem cells in the shoot apical meristem in an undifferentiated state. The mechanism by which WUS prevents the differentiation of stem cells is unknown. We have characterized a meristem maintenance mutant in Antirrhinum majus and shown that it arises from a defect in the WUS orthologue ROSULATA (ROA). Detailed characterization of a semidominant roa allele revealed an essential role for the conserved C-terminal domain. Expression of either ROA or WUS lacking this domain causes a failure of meristem maintenance. The conserved domain mediates an interaction between WUS and two members of a small family of corepressor-like proteins in Arabidopsis. Our results suggest that WUS functions by recruiting transcriptional corepressors to repress target genes that promote differentiation, thereby ensuring stem cell maintenance.
Kieffer
Martin
M
Centre for Plant Sciences, University of Leeds, Leeds LS2 9JT, United Kingdom.
Stern
Yaniv
Y
Cook
Holly
H
Clerici
Elena
E
Maulbetsch
Christoph
C
Laux
Thomas
T
Davies
Brendan
B
D000483:Alleles; D000595:Amino Acid Sequence; D032161:Antirrhinum / Q000166:cytology* / Q000235:genetics / Q000378:metabolism; D017360:Arabidopsis / Q000166:cytology* / Q000235:genetics / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000737:chemistry* / Q000378:metabolism / Q000502:physiology; D002454:Cell Differentiation / Q000235:genetics; D017124:Conserved Sequence; D018398:Homeodomain Proteins / Q000737:chemistry* / Q000378:metabolism / Q000502:physiology; D018519:Meristem / Q000166:cytology* / Q000378:metabolism / Q000648:ultrastructure; D008969:Molecular Sequence Data; D010641:Phenotype; D010802:Phylogeny; D010940:Plant Proteins / Q000737:chemistry* / Q000378:metabolism / Q000502:physiology; D025941:Protein Interaction Mapping; D017434:Protein Structure, Tertiary; D012097:Repressor Proteins / Q000737:chemistry / Q000378:metabolism; D016415:Sequence Alignment; D014157:Transcription Factors / Q000737:chemistry / Q000378:metabolism / Q000502:physiology
D029681:Arabidopsis Proteins; D018398:Homeodomain Proteins; D010940:Plant Proteins; D012097:Repressor Proteins; D014157:Transcription Factors; C510418:WSIP2 protein, Arabidopsis; C116421:WUSCHEL protein, Arabidopsis; C511291:At1g15750 protein, Arabidopsis