PMID- 7821715
OWN - NLM
STAT- MEDLINE
DCOM- 19950216
LR  - 20190813
IS  - 0303-7207 (Print)
IS  - 0303-7207 (Linking)
VI  - 105
IP  - 1
DP  - 1994 Oct
TI  - Quantitative increases in DNA binding affinity and positional effects determine 
      9-cis retinoic acid induced activation of the retinoid X receptor beta homodimer.
PG  - 27-35
AB  - Retinoid X receptors (RXRs) exert transcriptional activities through 
      heterodimerization with members of the nuclear hormone receptor superfamily. RXRs 
      also act as homodimers and stimulate transcription from an RXR responsive element 
      (RXRE) when bound to 9-cis-retinoic acid (9cRA). Here direct effects of 9cRA have 
      been examined on biochemical and mechanistic parameters of RXR beta. It is shown 
      that 9cRA significantly increases RXR beta homodimer binding affinity to an RXRE 
      (Kd without ligand = 18 nM, Kd with ligand = 6 nM), while decreasing 
      significantly the affinity of RXR beta/thyroid hormone receptor (T3R alpha) 
      heterodimer binding to the same element. Effects on other response elements are 
      also examined. The RXR beta homodimer was found to contact both halves of the 
      RXRE direct repeat, irrespective of the effect of added ligand, while the RXR 
      beta/T3R alpha heterodimer contacted the element only through a specific 
      half-site. Binding of the homodimer to the element functionally activates RXR 
      beta, since RXR beta enhanced transcription in vitro from a specific template in 
      a ligand-dependent fashion. In agreement, transfection of RXR beta alone (but not 
      RXR beta/T3R alpha) led to ligand-dependent activation of a reporter containing 
      the RXRE. Taken together, 9cRA facilitates functional activation of the RXR beta 
      homodimer in an element-dependent manner.
FAU - Medin, J A
AU  - Medin JA
AD  - Laboratory of Molecular Growth Regulation, National Institute of Child Health and 
      Human Development, National Institutes of Health, Bethesda, MD 20892.
FAU - Minucci, S
AU  - Minucci S
FAU - Driggers, P H
AU  - Driggers PH
FAU - Lee, I J
AU  - Lee IJ
FAU - Ozato, K
AU  - Ozato K
LA  - eng
PT  - Journal Article
PT  - Research Support, Non-U.S. Gov't
PL  - Ireland
TA  - Mol Cell Endocrinol
JT  - Molecular and cellular endocrinology
JID - 7500844
RN  - 0 (Macromolecular Substances)
RN  - 0 (Receptors, Retinoic Acid)
RN  - 0 (Recombinant Proteins)
RN  - 0 (Retinoid X Receptors)
RN  - 0 (Transcription Factors)
RN  - 0 (retinoic acid binding protein II, cellular)
RN  - 5688UTC01R (Tretinoin)
RN  - 9007-49-2 (DNA)
SB  - IM
MH  - Animals
MH  - Baculoviridae/genetics
MH  - Base Sequence
MH  - DNA/*metabolism
MH  - Macromolecular Substances
MH  - Molecular Sequence Data
MH  - Plasmids
MH  - Promoter Regions, Genetic
MH  - Rats
MH  - Receptors, Retinoic Acid/drug effects/genetics/*metabolism
MH  - Recombinant Proteins/metabolism
MH  - Repetitive Sequences, Nucleic Acid
MH  - Retinoid X Receptors
MH  - Spodoptera/metabolism
MH  - Templates, Genetic
MH  - Transcription Factors/drug effects/genetics/*metabolism
MH  - Transcription, Genetic
MH  - Transfection
MH  - Tretinoin/*pharmacology
MH  - Tumor Cells, Cultured
EDAT- 1994/10/01 00:00
MHDA- 1994/10/01 00:01
CRDT- 1994/10/01 00:00
PHST- 1994/10/01 00:00 [pubmed]
PHST- 1994/10/01 00:01 [medline]
PHST- 1994/10/01 00:00 [entrez]
AID - 10.1016/0303-7207(94)90032-9 [doi]
PST - ppublish
SO  - Mol Cell Endocrinol. 1994 Oct;105(1):27-35. doi: 10.1016/0303-7207(94)90032-9.