RXR beta: a coregulator that enhances binding of retinoic acid, thyroid hormone, and vitamin D receptors to their cognate response elements.
The retinoic acid receptor (RAR) requires coregulators to bind effectively to response elements in target genes. A strategy of sequential screening of expression libraries with a retinoic acid response element and RAR identified a cDNA encoding a coregulator highly related to RXR alpha. This protein, termed RXR beta, forms heterodimers with RAR, preferentially increasing its DNA binding and transcriptional activity on promoters containing retinoic acid, but not thyroid hormone or vitamin D, response elements. Remarkably, RXR beta also heterodimerizes with the thyroid hormone and vitamin D receptors, increasing both DNA binding and transcriptional function on their respective response elements. RXR alpha also forms heterodimers with these receptors. These observations suggest that retinoid X receptors meet the criteria for biochemically characterized cellular coregulators and serve to selectively target the high affinity binding of retinoic acid, thyroid hormone, and vitamin D receptors to their cognate DNA response elements.
Yu
V C
VC
Eukaryotic Regulatory Biology Program, University of California, San Diego.
Delsert
C
C
Andersen
B
B
Holloway
J M
JM
Devary
O V
OV
Näär
A M
AM
Kim
S Y
SY
Boutin
J M
JM
Glass
C K
CK
Rosenfeld
M G
MG
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D002352:Carrier Proteins / Q000378:metabolism*; D003001:Cloning, Molecular; D004247:DNA / Q000235:genetics; D004268:DNA-Binding Proteins / Q000378:metabolism* / Q000502:physiology*; D015870:Gene Expression; D005786:Gene Expression Regulation; D046911:Macromolecular Substances; D008969:Molecular Sequence Data; D011485:Protein Binding; D012333:RNA, Messenger / Q000235:genetics; D051381:Rats; D018167:Receptors, Calcitriol; D018168:Receptors, Retinoic Acid; D011987:Receptors, Steroid / Q000378:metabolism*; D011988:Receptors, Thyroid Hormone / Q000378:metabolism*; D012045:Regulatory Sequences, Nucleic Acid; D013329:Structure-Activity Relationship; D014158:Transcription, Genetic; D014212:Tretinoin / Q000378:metabolism; D014807:Vitamin D / Q000502:physiology
D002352:Carrier Proteins; D004268:DNA-Binding Proteins; D046911:Macromolecular Substances; D012333:RNA, Messenger; D018167:Receptors, Calcitriol; D018168:Receptors, Retinoic Acid; D011987:Receptors, Steroid; D011988:Receptors, Thyroid Hormone; D014807:Vitamin D; D014212:Tretinoin; D004247:DNA