Los Elementos y Moléculas de la Vida Losada, Vargas, Florencio y De la Rosa (1998-9) Editorial Rueda, Madrid

James Watson (L) and Francis Crick (R), and the model they built of the structure of DNA in 1953

ÁCIDO DESOXIRRIBONUCLEICO..\..\PcMolecule Lite (Demo)\Mols\DNA.mcm..\..\PcMolecule Lite (Demo)\Mols\DNA.mcm..\..\..\Mis documentos\webdpto\biomoleculas\biomodel\model1\INICIO.HTM Los Elementos y Moléculas de la Vida Losada, Vargas, Florencio y De la Rosa (1998-9) Editorial Rueda, Madrid

Los Elementos y Moléculas de la Vida Losada, Vargas, Florencio y De la Rosa (1998-9) Editorial Rueda, Madrid

International Human Genome Sequencing Consortium Nature 409, (2001)

International Human Genome Sequencing Consortium Nature 409, (2001) The automated production line for sample preparation at the Whitehead Institute, Center for Genome Research

International Human Genome Sequencing Consortium Nature 409, (2001) Conserved segments in the human and mouse genome Human chromosomes, with segments containing at least two genes whose order is conserved in the mouse genome as colour blocks. Each colour corresponds to a particular mouse chromosome.

Distribution of the molecular functions of 26,383 human genes The sequence of Human Genome Venter et al. (2001) Science 291,

International Human Genome Sequencing Consortium Nature 409, (2001) Conservation of architectures between animal species

The Helicobacter pylori chromosome Each color represents a different functional group of genes Tomb et al. (1997) Nature 388, 539

Mycobacterium tuberculosis

The first tree genome (Populus) will be sequenced by 2003 News in Nature (2002) 415,

8.2 Example mutants in Drosophila Figure 8-8 Mutations may cause only subtle changes or may produce significant changes in development, cellular function, appearance and/or behavior

Genes y Proteínas

Interacciones Ác. nucleicos - Proteínas Fuertes (t = s, min) Nucleosoma (DNA) Ribosoma (RNA) Débiles (t =  s, ms) Polimerasas..\..\..\Mis documentos\webdpto\biomoleculas\biomodel\model1\INICIO.HTM

9.5 Nucleosomes are complexes of histones Figure 9-30

9.5 The solenoid model of condensed chromatin Figure 9-31

9.6 A model for chromatin packing in metaphase chromosomes Figure 9-35

9.6 Chromosome number, size and shape at metaphase are species specific Figure 9-33

10.5 Transcriptional activators are modular proteins composed of distinct functional domains Figure 10-39

DNA-binding domains can be classified into numerous structural types Homeodomain proteins Zinc-finger proteins Winged-helix (forkhead) proteins Leucine-zipper proteins Helix-loop-helix proteins

Interaction between a zinc- finger protein and DNA

Interaction of a homodimeric leucine- zipper protein and DNA

Interaction of a helix-loop-helix in a homodimeric protein and DNA

A new family of plant transcription factors displays a novel ssDNA-binding surface Desveaux et al. (2002) Nature Struct Biol 9, 512 Whirligig tetrameric structure of p24The p24 protomer

A new family of plant transcription factors displays a novel ssDNA-binding surface Desveaux et al. (2002) Nature Struct Biol 9, 512 Putative ssDNA-binding residues of a p24 protomer, corresponding to the subunit shown in the lower left hand corner of the left picture Binding of p24 to melted dsDNA

D.J. Patel (2002) Nature 417, 807 Basics of the quadruplex topology of human telomeric repeat sequences Telomeres are protein–DNA structures protecting the ends of chromosomes

G.N. Parkinson et al. (2002) Nature 417, 876 Structure of the quadruplex formed by the four- repeat TTAGGG human telomere DNA sequence. The central potassium counter ion is coordinated in a bipyramidyl antiprismatic arrangement by the electronegative carbonyl groups of guanine O6

D.J. Patel (2002) Nature 417, 807 a) The K + -stabilized crystal structure b) The Na + -stabilized solution structure The folding and appearance of the telomeric DNA sequence is fundamentally different in K + - and Na + -containing quadruplex structures

Clinical implications. The enzyme telomerase is highly expressed only in tumour cells, enabling them to carry on replicating their chromosomes almost indefinitely. (In non- tumour cells, by contrast, telomerase is not expressed and telomeres gradually erode to the point at which cells cannot duplicate their DNA safely, and so no longer divide.) So telomerase is a promising drug target. It binds to single-stranded telomere ends, and could potentially be inhibited by drugs that compete for these ends (in their quadruplex form). D.J. Patel (2002) Nature 417, 807

A G G G G A A T C C C C T T 3´ 5´ ESTRUCTURA DEL DNA T T A A