Heterodimerization of the Yeast Homeodomain Transcriptional Regulators .alpha.2 and a1: Secondary Structure Determination of the a1 Homeodomain and Changes Produced by .alpha.2 Interactions
| العنوان: | Heterodimerization of the Yeast Homeodomain Transcriptional Regulators .alpha.2 and a1: Secondary Structure Determination of the a1 Homeodomain and Changes Produced by .alpha.2 Interactions |
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| المؤلفون: | Dahlquist Fw, Baxter Sm, Phillips Cl, Roth Af, Gontrum Dm |
| المصدر: | Biochemistry. 33:15309-15320 |
| بيانات النشر: | American Chemical Society (ACS), 1994. |
| سنة النشر: | 1994 |
| مصطلحات موضوعية: | Magnetic Resonance Spectroscopy, Receptors, Peptide, Macromolecular Substances, Stereochemistry, Molecular Sequence Data, Cooperativity, Saccharomyces cerevisiae, Biochemistry, Protein Structure, Secondary, Turn (biochemistry), chemistry.chemical_compound, Gene Expression Regulation, Fungal, Amino Acid Sequence, Protein secondary structure, Homeodomain Proteins, chemistry.chemical_classification, Chemistry, Hydrogen Bonding, Nuclear magnetic resonance spectroscopy, NKX-homeodomain factor, Molecular biology, Recombinant Proteins, Amino acid, Receptors, Mating Factor, Helix, DNA, Protein Binding, Transcription Factors |
| الوصف: | The homeodomain proteins, a1 and alpha 2, act cooperatively to regulate cell-type specific genes in yeast. The basis of this cooperativity is an interaction between the two proteins, forming a heterodimer that binds DNA tightly and specifically. A fragment containing the homeodomain of a1, a1(66-126), has been studied by NMR spectroscopy to gain secondary structure information and to characterize the changes in a1 upon heterodimerization with alpha 2. Heteronuclear (1H-15N) NMR methods were used to assign backbone resonances of the 61 amino acid fragment. The a1(66-126) secondary structure was determined using NOE connectivities, 3JHN alpha coupling constants and hydrogen exchange kinetic data. NMR data identify three helical segments separated by a loop and a tight turn that are the characteristic structural elements of homeodomain proteins. The a1 fragment was titrated with alpha 2(128-210), the homeodomain-containing fragment of alpha 2, to study changes in a1(66-126) spectra produced by alpha 2 binding. The a1(66-126) protein was labeled with 15N and selectively observed using isotope-edited NMR experiments. NMR spectra of bound a1(66-126) indicate that residues in helix 1, helix 2, and the loop connecting them are directly involved in the binding of the alpha 2 fragment. Relatively minor effects on the resonances from residues in helix 3, the putative DNA-binding helix, were noted upon alpha 2 binding. We have thus located a region of the a1 homeodomain important for specific protein recognition. |
| تدمد: | 1520-4995 0006-2960 |
| الوصول الحر: | https://explore.openaire.eu/search/publication?articleId=doi_dedup___::f3ec327a54fe72ba0e2c48088206b554Test https://doi.org/10.1021/bi00255a012Test |
| رقم الانضمام: | edsair.doi.dedup.....f3ec327a54fe72ba0e2c48088206b554 |
| قاعدة البيانات: | OpenAIRE |
| تدمد: | 15204995 00062960 |
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