PMID- 22167189
OWN - NLM
STAT- MEDLINE
DCOM- 20120409
LR  - 20240321
IS  - 1083-351X (Electronic)
IS  - 0021-9258 (Print)
IS  - 0021-9258 (Linking)
VI  - 287
IP  - 8
DP  - 2012 Feb 17
TI  - REF4 and RFR1, subunits of the transcriptional coregulatory complex mediator, are 
      required for phenylpropanoid homeostasis in Arabidopsis.
PG  - 5434-45
LID - 10.1074/jbc.M111.312298 [doi]
AB  - The plant phenylpropanoid pathway produces an array of metabolites that impact 
      human health and the utility of feed and fiber crops. We previously characterized 
      several Arabidopsis thaliana mutants with dominant mutations in REDUCED EPIDERMAL 
      FLUORESCENCE 4 (REF4) that cause dwarfing and decreased accumulation of 
      phenylpropanoids. In contrast, ref4 null plants are of normal stature and have no 
      apparent defect in phenylpropanoid biosynthesis. Here we show that disruption of 
      both REF4 and its paralog, REF4-RELATED 1 (RFR1), results in enhanced expression 
      of multiple phenylpropanoid biosynthetic genes, as well as increased accumulation 
      of numerous downstream products. We also show that the dominant ref4-3 mutant 
      protein interferes with the ability of the PAP1/MYB75 transcription factor to 
      induce the expression of PAL1 and drive anthocyanin accumulation. Consistent with 
      our experimental results, both REF4 and RFR1 have been shown to physically 
      associate with the conserved transcriptional coregulatory complex, Mediator, 
      which transduces information from cis-acting DNA elements to RNA polymerase II at 
      the core promoter. Taken together, our data provide critical genetic support for 
      a functional role of REF4 and RFR1 in the Mediator complex, and for Mediator in 
      the maintenance of phenylpropanoid homeostasis. Finally, we show that wild-type 
      RFR1 substantially mitigates the phenotype of the dominant ref4-3 mutant, 
      suggesting that REF4 and RFR1 may compete with one another for common binding 
      partners or for occupancy in Mediator. Determining the functions of diverse 
      Mediator subunits is essential to understand eukaryotic gene regulation, and to 
      facilitate rational manipulation of plant metabolic pathways to better suit human 
      needs.
FAU - Bonawitz, Nicholas D
AU  - Bonawitz ND
AD  - Department of Biochemistry, Purdue University, West Lafayette, Indiana 
      47907-2063, USA.
FAU - Soltau, Whitney L
AU  - Soltau WL
FAU - Blatchley, Michael R
AU  - Blatchley MR
FAU - Powers, Brendan L
AU  - Powers BL
FAU - Hurlock, Anna K
AU  - Hurlock AK
FAU - Seals, Leslie A
AU  - Seals LA
FAU - Weng, Jing-Ke
AU  - Weng JK
FAU - Stout, Jake
AU  - Stout J
FAU - Chapple, Clint
AU  - Chapple C
LA  - eng
GR  - Howard Hughes Medical Institute/United States
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PT  - Research Support, U.S. Gov't, Non-P.H.S.
DEP - 20111213
PL  - United States
TA  - J Biol Chem
JT  - The Journal of biological chemistry
JID - 2985121R
RN  - 0 (Arabidopsis Proteins)
RN  - 0 (Membrane Proteins)
RN  - 0 (Organic Chemicals)
RN  - 0 (Pancreatitis-Associated Proteins)
RN  - 0 (Protein Subunits)
RN  - 0 (REF4 protein, Arabidopsis)
RN  - 0 (REG3A protein, human)
RN  - 0 (RNA, Messenger)
SB  - IM
MH  - Arabidopsis/anatomy & histology/genetics/*metabolism
MH  - Arabidopsis Proteins/chemistry/genetics/*metabolism
MH  - *Gene Expression Regulation, Plant
MH  - Homeostasis/*genetics
MH  - Membrane Proteins/chemistry/deficiency/genetics/*metabolism
MH  - Mutation
MH  - Organic Chemicals/*metabolism
MH  - Pancreatitis-Associated Proteins
MH  - Phenotype
MH  - Phylogeny
MH  - Protein Subunits/metabolism
MH  - RNA, Messenger/genetics/metabolism
MH  - Sequence Homology, Amino Acid
MH  - *Transcription, Genetic
PMC - PMC3285322
EDAT- 2011/12/15 06:00
MHDA- 2012/04/10 06:00
PMCR- 2013/02/17
CRDT- 2011/12/15 06:00
PHST- 2011/12/15 06:00 [entrez]
PHST- 2011/12/15 06:00 [pubmed]
PHST- 2012/04/10 06:00 [medline]
PHST- 2013/02/17 00:00 [pmc-release]
AID - S0021-9258(20)61205-4 [pii]
AID - M111.312298 [pii]
AID - 10.1074/jbc.M111.312298 [doi]
PST - ppublish
SO  - J Biol Chem. 2012 Feb 17;287(8):5434-45. doi: 10.1074/jbc.M111.312298. Epub 2011 
      Dec 13.