ANGUSTIFOLIA3 binds to SWI/SNF chromatin remodeling complexes to regulate transcription during Arabidopsis leaf development.
The transcriptional coactivator ANGUSTIFOLIA3 (AN3) stimulates cell proliferation during Arabidopsis thaliana leaf development, but the molecular mechanism is largely unknown. Here, we show that inducible nuclear localization of AN3 during initial leaf growth results in differential expression of important transcriptional regulators, including GROWTH REGULATING FACTORs (GRFs). Chromatin purification further revealed the presence of AN3 at the loci of GRF5, GRF6, CYTOKININ RESPONSE FACTOR2, CONSTANS-LIKE5 (COL5), HECATE1 (HEC1), and ARABIDOPSIS RESPONSE REGULATOR4 (ARR4). Tandem affinity purification of protein complexes using AN3 as bait identified plant SWITCH/SUCROSE NONFERMENTING (SWI/SNF) chromatin remodeling complexes formed around the ATPases BRAHMA (BRM) or SPLAYED. Moreover, SWI/SNF ASSOCIATED PROTEIN 73B (SWP73B) is recruited by AN3 to the promoters of GRF5, GRF3, COL5, and ARR4, and both SWP73B and BRM occupy the HEC1 promoter. Furthermore, we show that AN3 and BRM genetically interact. The data indicate that AN3 associates with chromatin remodelers to regulate transcription. In addition, modification of SWI3C expression levels increases leaf size, underlining the importance of chromatin dynamics for growth regulation. Our results place the SWI/SNF-AN3 module as a major player at the transition from cell proliferation to cell differentiation in a developing leaf.
Department of Plant Systems Biology, VIB, 9052 Ghent, Belgium.
Liesbeth
L
Vercruyssen
Aurine
A
Verkest
Nathalie
N
Gonzalez
Ken S
KS
Heyndrickx
Dominique
D
Eeckhout
Soon-Ki
SK
Han
Teddy
T
Jégu
Rafal
R
Archacki
Jelle
J
Van Leene
Megan
M
Andriankaja
Stefanie
S
De Bodt
Thomas
T
Abeel
Frederik
F
Coppens
Stijn
S
Dhondt
Liesbeth
L
De Milde
Mattias
M
Vermeersch
Katrien
K
Maleux
Kris
K
Gevaert
Andrzej
A
Jerzmanowski
Moussa
M
Benhamed
Doris
D
Wagner
Klaas
K
Vandepoele
Geert
G
De Jaeger
Dirk
D
Inzé
D000251:Adenosine Triphosphatases / Q000378:metabolism; D017360:Arabidopsis / Q000166:cytology / Q000235:genetics* / Q000254:growth & development; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D001665:Binding Sites; D002454:Cell Differentiation; D049109:Cell Proliferation; D042002:Chromatin Assembly and Disassembly; D002868:Chromosomal Proteins, Non-Histone / Q000378:metabolism / Q000502:physiology; D019926:Cyclin B / Q000235:genetics / Q000378:metabolism; D018506:Gene Expression Regulation, Plant; D018745:Genome, Plant; D018515:Plant Leaves / Q000166:cytology / Q000235:genetics / Q000254:growth & development; D011401:Promoter Regions, Genetic; D012097:Repressor Proteins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*
D000251:Adenosine Triphosphatases; D029681:Arabidopsis Proteins; D002868:Chromosomal Proteins, Non-Histone; D019926:Cyclin B; D012097:Repressor Proteins; C452846:DETORQEO protein, Arabidopsis; C462528:CycB1 protein, Arabidopsis; C587486:SWI3C protein, Arabidopsis; C514541:BRM protein, Arabidopsis