The Variety of DNA-Binding Proteins

The Variety of DNA-Binding Proteins 1631 Table 28-1 Nucleotide Sequences of Some Commonly... 

The leucine zipper DNA-binding proteins, described in Chapter 10, are examples of globular proteins that use coiled coils to form both homo- and heterodimers. A variety of fibrous proteins also have heptad repeats in their sequences and use coiled coils to form oligomers, mainly dimers and trimers. Among these are myosin, fibrinogen, actin cross-linking proteins such as spectrin and dystrophin as well as the intermediate filament proteins keratin, vimentin, desmin, and neurofilament proteins. 

The higher-order architectures of DNA/protein complexes are achieved on the balance of the physical properties of DNA and the interactive forces of DNA-binding proteins (Hizume et al., 2002 Yoshimura et al, 2000). The superhelical strain of the DNA has been suggested to play a critical role in a variety of genome events such as transcriptional regulation and DNA replication (Opel et al, 2001). 

AD. Baxevanis, G. Arents, E.N. Moudrianakis, and D. Landsman. 1995. A variety of DNA-binding and multimeric proteins contain the histone fold motif Nucleic Acids Res. 23 2685-2691. (PubMed)... 

S. cerevisiae felomers have 350 base pairs confaining fhe sequences (TGj 3 / C 3A) as well as one or more copies of a 6.7-kb nonrepefihve sequence and ofher elemenfs. In many species fhe repehfive felo-meric sequences have 3 poly(G) fails at the ends of fhe DNA molecules. These fails are able to form G quarfef sfrucfures (Fig. 5-26 and Chapter 5, Sechon C,4). A variety of telomere-binding proteins have been isolated. " Some of fhese bind to G quartet struc-... 

The more we learn about the biology and biochemistry of DNA methylation, the more fascinating and challenging the field becomes. The last decade has witnessed a significant progress in our knowledge we learned that there are many enzymes involved in methylation/demethylation of DNA we appreciated the discovery of proteins that bind specifically to methylated DNA sequences to recruit numerous other proteins with a variety of functions we realized that the effect of DNA... 

GGGCGG), is usually quite near the TATA box. The DNA-binding domain of the Spl protein is near its carboxyl terminus and contains three zinc fingers. Two other domains in Spl function in activation, and are notable in that 25% of their amino acid residues are Gin. A wide variety of other activator proteins also have these glutamine-rich domains. 

Study of other rare hereditary cancers has led to the location of 20 or more additional probable tumor-suppressor genes. One of these, p53, is inactive in over 50% of all human cancers and over 90% of sqamous cell carcinomas of the skin.ee In small-cell lung cancers and osteosarcoma both RB and p53 are inactive.2 Protein p53 is a stronger tumor suppressor than protein Rb. Results of a variety of experiments have suggested that p53, a DNA-binding protein of known structure, plays a key role in checking DNA for damage at the C,... 

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