Stem Cell Concept

Pg. 721

Signal Transduction Pathways and Cell Differentiation

Specialized cell type(neuron, skin cell, red blood cell, etc.)

Stem Cell

Blood Cell Formation

Erythropoietin (Epo)

(Epo)

Red Blood Cell Development

EPO

Synthesis of proteins that stimulate Red Blood Cell development andprevent apoptosis

Negative Regulation of JAK/STAT Pathway

Mutant EPO Receptor

PP

Signal toActivate

Seven-Pass ReceptorsAdrenalineGlucogonTSH, LH

Cell TypesHeart muscleSkeletal muscleThyroidOvaryKidneyIntestinal epithelia

ContractionGlycogen breakdownHormone secretionWater retentionIon transportPg. 546

Activation of Galpha Subunit

Synthesis of cyclic AMP

ATP

cyclic AMP

Adenylyl Cyclase

Pg. 550

Protein Kinase A (PKA)CFTROther Proteins

TargetsTranscription FactorsEnzymes

Actin Microtubules Intermediatefilaments

Cytoskeletal Structures

Chapter 17

Microtubules

Vesicle Transport

Chromosome segregation(mitotic spindle)

Cilia/Flagella

Tubulin Dimer

GTP

GTP

GFP-Tagged Centrosomes

Centrosome Structure

TaxolColchicine

Pacific YewAutumn crocus

Microtubule “Poisons”

Tau Protein Stabilizes Microtubules in Neurons

Tau Protein

Tau “tangles”

Regulation of Microtubule Stability by Tau

Alzheimer’s Brain

Alzheimer’s Brain

Tau Protein

Microtubule “Motor” Proteins

Microtubule “Motor” Proteins

GFP-Tagged Centrosomes

Centrosome Duplication Cycle

Ciliated Cells

Actin Filaments

Actin Monomer

Arp2/3 (Actin Related Proteins)

Arp2

Arp3

Gelsolin Protein

New minus end

New plus end

Acton Poisons

Myosin-II

Muscle Cell

Sarcomere

Contraction of a Sarcomere

Resting Muscle

Rigor position

Contraction of a Sarcomere

Tropomyosin blocksaccess to actin filament

Ca2+

Binds Troponin C

Muscle Cell

Muscle Relaxants

Pancuronium Baclofen

Ligand for Seven-pass receptorInhibits Ligand-gated ion channels

Muscle Cell

Muscle Cell

Pancuronium

Muscle cell membrane can not be de-polarized

Baclofin

Muscle CellMembrane

Muscle CellMembrane

Muscle cell membrane can not be de-polarized

Muscular Dystrophy

Dystrophin gene (2.4 million bp, 78 exons)

X-linked Recessive

Progressive muscle weakness/loss of skeletal muscle

Pg. 574

Pg. 576

Pg. 577

Pg. 575

Keratin Filaments

Desmosome

Pg. 715

Pg. 577

Epidermolysis Bullosa(Keratin mutations)

Pg. 577

Epidermolysis Bullosa(Keratin mutations)

Mitotic Cell Cycle

DNAReplication

G1 S G2

G1

M-Phase

(G1 Phase)

(G2 Phase)

Semi-Conservative DNA Replication

Binding site forOrigin Recognition Complex (ORC)

(ORC)

Completing Synthesis of the Lagging Strand

(5’ to 3” exonuclease)*

*

Thymine Tautomers

Pairs with Adenine Pairs with Guanine

(common form) (rare form)

DNA Polymerase “proof reading”

End Replication Problem

Final RNA primers removed

Second round ofDNA replication

First round ofDNA replication

*

*

*

*

A

Telomere Synthesis

Telomerase RNA

156 nucleotides

Telomere Synthesis

Normal Cell Telomeres

Short Telomeres

Apoptosis

Chromosome Instabilty/DNA Damage

Telomerase Inhibitor

Apoptosis

Telomostatin

~ 90 of all cancers haveRe-activated telomerase

Mitotic Cell Cycle

DNAReplication

G1 S G2

G1

M-Phase

Cohesion of Sister Chromatids

Cohesin “ring”

Nuclear Lamina

Fig. 19-18 (replacement)

Interphase and M-Phase Chromosomes

Condensation of Chromatids

Microtubules

Centrosome Duplication Cycle

Mitotic Spindle

Pg. 641

Metaphase Anaphase

Pg. 257

Ubiquitin-dependent Protein Degradation

Proteasome

Amino acids + Ub

Protein Ub-Ub-Ub

Protein + Ub

APC (Ubiquitin Ligase)

Start of Anaphase

P

Anaphase “A” and “B”

Cytokinesis

Myosin II - GFP

Interphase Telophase Cytokinesis

CytokinesisCytokinesis G1

“Contractile Unit” in Cytokinesis

Fig. 17-41

Plasma Membrane

Cytosol

Septin“ring”