Spatiotemporal regulation of cell-cycle genes by SHORTROOT links patterning and growth.
The development of multicellular organisms relies on the coordinated control of cell divisions leading to proper patterning and growth. The molecular mechanisms underlying pattern formation, particularly the regulation of formative cell divisions, remain poorly understood. In Arabidopsis, formative divisions generating the root ground tissue are controlled by SHORTROOT (SHR) and SCARECROW (SCR). Here we show, using cell-type-specific transcriptional effects of SHR and SCR combined with data from chromatin immunoprecipitation-based microarray experiments, that SHR regulates the spatiotemporal activation of specific genes involved in cell division. Coincident with the onset of a specific formative division, SHR and SCR directly activate a D-type cyclin; furthermore, altering the expression of this cyclin resulted in formative division defects. Our results indicate that proper pattern formation is achieved through transcriptional regulation of specific cell-cycle genes in a cell-type- and developmental-stage-specific context. Taken together, we provide evidence for a direct link between developmental regulators, specific components of the cell-cycle machinery and organ patterning.
Sozzani
R
R
Department of Biology and IGSP Center for Systems Biology, Duke University, Durham, North Carolina 27708, USA.
Cui
H
H
Moreno-Risueno
M A
MA
Busch
W
W
Van Norman
J M
JM
Vernoux
T
T
Brady
S M
SM
Dewitte
W
W
Murray
J A H
JA
Benfey
P N
PN
D017360:Arabidopsis / Q000166:cytology / Q000196:embryology / Q000235:genetics* / Q000254:growth & development*; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism*; D019521:Body Patterning / Q000235:genetics* / Q000502:physiology*; D002453:Cell Cycle / Q000235:genetics / Q000502:physiology; D002455:Cell Division / Q000235:genetics; D056741:Cyclin D / Q000235:genetics / Q000378:metabolism; D018844:Cyclin-Dependent Kinases / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D018816:Genes, cdc / Q000502:physiology*; D038081:Organogenesis / Q000235:genetics / Q000502:physiology; D018517:Plant Roots / Q000166:cytology / Q000196:embryology / Q000235:genetics / Q000254:growth & development; D013997:Time Factors; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*
D029681:Arabidopsis Proteins; D056741:Cyclin D; C100978:SCR protein, Arabidopsis; C410510:SHORT ROOT protein, Arabidopsis; D014157:Transcription Factors; D018844:Cyclin-Dependent Kinases