Figure 7.18 Genomes 3 ( Garland Science 2007) Relationship
between the human gene catalog and the catalogs of other
organisms
Slide 14
Chromatin organization
Slide 15
Slide 16
Slide 17
General features of eukaryotic chromosomes Origin of
replication
Slide 18
Centromeres are necessary for correct segregation of
chromosomes to daughter cells in cell division Centromeres
associate with proteins to form kinetochores, i.e. attachment sites
for microtubules
Slide 19
Centromeres vary in size. Most consist of tandem repeats.
Slide 20
General features of eukaryotic chromosomes Origin of
replication
Slide 21
Telomeres consist of tandemly repeated DNA (minisatellites) at
the ends of chromosomes. They maintain the ends of linear
chromosomes. 5-TTAGGG-3 is the repeat unit in humans.
Slide 22
Chromatin organization is not fixed Cell cycle
Slide 23
Chromatin organization is not fixed
Slide 24
Cohesin- and condensin protein complexes induce formation of M
phase chromosomes.
Slide 25
Chromatin organization is not fixed
Slide 26
Proteolysis of cohesins allows segregation of sister
chromatids. Proteolysis of condensins leads to interphase
chromosomes.
Slide 27
Mitosis Meiosis
Slide 28
Chromatin organization is not fixed Interphase M-phase
Slide 29
General organization of interphase chromatin in the
nucleus
Slide 30
Nucleosomes
Slide 31
Histones are the core proteins of nucleosomes
Slide 32
Histones are the core proteins of nucleosomes
Slide 33
Histones are the core proteins of nucleosomes
Slide 34
Histones are the core proteins of nucleosomes
Slide 35
Assembly of nucleosomes is promoted by histone chaperones
Slide 36
Assembly of nucleosomes is promoted by histone chaperones
Slide 37
Histone H1 is a linker histone
Slide 38
Structural changes in nucleosome positioning in the presence of
linker histone H1 no H1 + H1
Slide 39
General organization of interphase chromatin in the
nucleus
Slide 40
Possible organization of the 30 nm fiber
Slide 41
Histone core modifications: CENP-A can replace histone H3 in
centromeres. H2A and H2B variants are found in histone cores.
Slide 42
General organization of interphase chromatin in the
nucleus
Slide 43
Nucleosome remodeling complexes alter the position of
nucleosomes
Slide 44
Nucleosome remodeling complexes alter the position of
nucleosomes
