scholarly journals Relationship between P-box Amino Acid Sequence and DNA Binding Specificity of the Thyroid Hormone Receptor.

1995 ◽  
Vol 270 (28) ◽  
pp. 16981-16987 ◽  
Author(s):  
Colleen C. Nelson ◽  
Stephen C. Hendy ◽  
Paul J. Romaniuk
Keyword(s):  
Amino Acid ◽  
Thyroid Hormone ◽  
Dna Binding ◽  
Amino Acid Sequence ◽  
Hormone Receptor ◽  
Thyroid Hormone Receptor ◽  
Binding Specificity ◽  
Dna Binding Specificity

scholarly journals A novel orphan receptor specific for a subset of thyroid hormone-responsive elements and its interaction with the retinoid/thyroid hormone receptor subfamily.

1994 ◽  
Vol 14 (10) ◽  
pp. 7025-7035 ◽  
Author(s):  
R Apfel ◽  
D Benbrook ◽  
E Lernhardt ◽  
M A Ortiz ◽  
G Salbert ◽  
...  
Keyword(s):  
Amino Acid ◽  
Thyroid Hormone ◽  
Dna Binding ◽  
Nuclear Receptors ◽  
Nuclear Receptor ◽  
Dna Sequences ◽  
Hormone Receptor ◽  
Thyroid Hormone Receptor ◽  
Orphan Receptor ◽  
Retinoid Receptor

The steroid/hormone nuclear receptor superfamily comprises several subfamilies of receptors that interact with overlapping DNA sequences and/or related ligands. The thyroid/retinoid hormone receptor subfamily has recently attracted much interest because of the complex network of its receptor interactions. The retinoid X receptors (RXRs), for instance, play a very central role in this subfamily, forming heterodimers with several receptors. Here we describe a novel member of this subfamily that interacts with RXR. Using a v-erbA probe, we obtained a cDNA which encodes a novel 445-amino-acid protein, RLD-1, that contains the characteristic domains of nuclear receptors. Northern (RNA) blot analysis showed that in mature rats, the receptor is highly expressed in spleen, pituitary, lung, liver, and fat. In addition, weaker expression is observed in several other tissues. Amino acid sequence alignment and DNA-binding data revealed that the DNA-binding domain of the new receptor is related to that of the thyroid/retinoid subgroup of nuclear receptors. RLD-1 preferentially binds as a heterodimer with RXR to a direct repeat of the half-site sequence 5'-G/AGGTCA-3', separated by four nucleotides (DR-4). Surprisingly, this binding is dependent to a high degree on the nature of the spacing nucleotides. None of the known nuclear receptor ligands activated RLD-1. In contrast, a DR-4-dependent constitutive transcriptional activation of a chloramphenicol acetyltransferase reporter gene by the RLD-1/RXR alpha heterodimer was observed. Our data suggest a highly specific role for this novel receptor within the network of gene regulation by the thyroid/retinoid receptor subfamily.

A novel orphan receptor specific for a subset of thyroid hormone-responsive elements and its interaction with the retinoid/thyroid hormone receptor subfamily

1994 ◽  
Vol 14 (10) ◽  
pp. 7025-7035
Author(s):  
R Apfel ◽  
D Benbrook ◽  
E Lernhardt ◽  
M A Ortiz ◽  
G Salbert ◽  
...  
Keyword(s):  
Amino Acid ◽  
Thyroid Hormone ◽  
Dna Binding ◽  
Nuclear Receptors ◽  
Nuclear Receptor ◽  
Dna Sequences ◽  
Hormone Receptor ◽  
Thyroid Hormone Receptor ◽  
Orphan Receptor ◽  
Retinoid Receptor

The steroid/hormone nuclear receptor superfamily comprises several subfamilies of receptors that interact with overlapping DNA sequences and/or related ligands. The thyroid/retinoid hormone receptor subfamily has recently attracted much interest because of the complex network of its receptor interactions. The retinoid X receptors (RXRs), for instance, play a very central role in this subfamily, forming heterodimers with several receptors. Here we describe a novel member of this subfamily that interacts with RXR. Using a v-erbA probe, we obtained a cDNA which encodes a novel 445-amino-acid protein, RLD-1, that contains the characteristic domains of nuclear receptors. Northern (RNA) blot analysis showed that in mature rats, the receptor is highly expressed in spleen, pituitary, lung, liver, and fat. In addition, weaker expression is observed in several other tissues. Amino acid sequence alignment and DNA-binding data revealed that the DNA-binding domain of the new receptor is related to that of the thyroid/retinoid subgroup of nuclear receptors. RLD-1 preferentially binds as a heterodimer with RXR to a direct repeat of the half-site sequence 5'-G/AGGTCA-3', separated by four nucleotides (DR-4). Surprisingly, this binding is dependent to a high degree on the nature of the spacing nucleotides. None of the known nuclear receptor ligands activated RLD-1. In contrast, a DR-4-dependent constitutive transcriptional activation of a chloramphenicol acetyltransferase reporter gene by the RLD-1/RXR alpha heterodimer was observed. Our data suggest a highly specific role for this novel receptor within the network of gene regulation by the thyroid/retinoid receptor subfamily.

scholarly journals The C6 zinc finger and adjacent amino acids determine DNA-binding specificity and affinity in the yeast activator proteins LAC9 and PPR1.

1990 ◽  
Vol 10 (10) ◽  
pp. 5128-5137 ◽  
Author(s):  
M M Witte ◽  
R C Dickson
Keyword(s):  
Amino Acids ◽  
Amino Acid ◽  
Dna Binding ◽  
Zinc Finger ◽  
Binding Specificity ◽  
Binding Domain ◽  
Dna Binding Domain ◽  
Transcription Activator ◽  
Activator Proteins ◽  
Dna Binding Specificity

LAC9 is a DNA-binding protein that regulates transcription of the lactose-galactose regulon in Kluyveromyces lactis. The DNA-binding domain is composed of a zinc finger and nearby amino acids (M. M. Witte and R. C. Dickson, Mol. Cell. Biol. 8:3726-3733, 1988). The single zinc finger appears to be structurally related to the zinc finger of many other fungal transcription activator proteins that contain positively charged residues and six conserved cysteines with the general form Cys-Xaa2-Cys-Xaa6-Cys-Xaa6-9-Cys-Xaa2-Cys-Xaa 6-Cys, where Xaan indicates a stretch of the indicated number of any amino acids (R. M. Evans and S. M. Hollenberg, Cell 52:1-3, 1988). The function(s) of the zinc finger and other amino acids in DNA-binding remains unclear. To determine which portion of the LAC9 DNA-binding domain mediates sequence recognition, we replaced the C6 zinc finger, amino acids adjacent to the carboxyl side of the zinc finger, or both with the analogous region from the Saccharomyces cerevisiae PPR1 or LEU3 protein. A chimeric LAC9 protein, LAC9(PPR1 34-61), carrying only the PPR1 zinc finger, retained the DNA-binding specificity of LAC9. However, LAC9(PPR1 34-75), carrying the PPR1 zinc finger and 14 amino acids on the carboxyl side of the zinc finger, gained the DNA-binding specificity of PPR1, indicating that these 14 amino acids are necessary for specific DNA binding. Our data show that C6 fingers can substitute for each other and allow DNA binding, but binding affinity is reduced. Thus, in a qualitative sense C6 fingers perform a similar function(s). However, the high-affinity binding required by natural C6 finger proteins demands a unique C6 finger with a specific amino acid sequence. This requirement may reflect conformational constraints, including interactions between the C6 finger and the carboxyl-adjacent amino acids; alternatively or in addition, it may indicate that unique, nonconserved amino acid residues in zinc fingers make sequence-specifying or stabilizing contacts with DNA.

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