Chapter 11 (p.206-225) Cell Communication

Yeast cell, mating type a Yeast cell, mating type  Figure 11.2  factor Receptor 1 Exchange of mating factors a  a factor Yeast cell, mating type a Yeast cell, mating type  2 Mating a  Figure 11.2 Communication between mating yeast cells. 3 New a/ cell a/

Individual rod-shaped cells Figure 11.3 1 Individual rod-shaped cells 2 Aggregation in progress 0.5 mm 3 Spore-forming structure (fruiting body) 2.5 mm Figure 11.3 Communication among bacteria. Fruiting bodies

Gap junctions between animal cells Plasmodesmata between plant cells Figure 11.4 Plasma membranes Gap junctions between animal cells Plasmodesmata between plant cells (a) Cell junctions Figure 11.4 Communication by direct contact between cells. (b) Cell-cell recognition

Neurotransmitter diffuses across synapse. Secreting cell Figure 11.5a Local signaling Target cell Electrical signal along nerve cell triggers release of neurotransmitter. Neurotransmitter diffuses across synapse. Secreting cell Secretory vesicle Figure 11.5 Local and long-distance cell signaling by secreted molecules in animals. Local regulator diffuses through extracellular fluid. Target cell is stimulated. (a) Paracrine signaling (b) Synaptic signaling

Long-distance signaling Figure 11.5b Long-distance signaling Endocrine cell Blood vessel Hormone travels in bloodstream. Target cell specifically binds hormone. Figure 11.5 Local and long-distance cell signaling by secreted molecules in animals. (c) Endocrine (hormonal) signaling

Figure 11.6-3 Figure 11.6 Overview of cell signaling.

1 2 3 Gate closed Ions Gate open Gate closed Plasma membrane Figure 11.7d 1 2 3 Gate closed Ions Gate open Gate closed Plasma membrane Cellular response Figure 11.7 Exploring: Cell-Surface Transmembrane Receptors

G protein-coupled receptor Plasma membrane Activated receptor Figure 11.7b G protein-coupled receptor Plasma membrane Activated receptor Signaling molecule Inactive enzyme GTP GDP GDP CYTOPLASM G protein (inactive) Enzyme GTP 1 2 GDP Activated enzyme Figure 11.7 Exploring: Cell-Surface Transmembrane Receptors GTP GDP P i 3 Cellular response 4

Signaling molecule (ligand) Ligand-binding site Figure 11.7c Signaling molecule (ligand) Ligand-binding site Signaling molecule Tyrosines Tyr Tyr Tyr Tyr Tyr Tyr Tyr Tyr Tyr Tyr Tyr Tyr Tyr Tyr Tyr Tyr Tyr Tyr CYTOPLASM Receptor tyrosine kinase proteins (inactive monomers) Dimer 1 2 Activated relay proteins Figure 11.7 Exploring: Cell-Surface Transmembrane Receptors Cellular response 1 Tyr Tyr P Tyr Tyr P Tyr Tyr P P Tyr Tyr P Tyr Tyr P P Tyr Tyr P Cellular response 2 Tyr Tyr P Tyr 6 ADP Tyr Tyr Tyr P 6 ATP P P Inactive relay proteins 3 4

Hormone (testosterone) EXTRACELLULAR FLUID Figure 11.9-5 Hormone (testosterone) EXTRACELLULAR FLUID Plasma membrane Receptor protein Hormone- receptor complex DNA Figure 11.9 Steroid hormone interacting with an intracellular receptor. mRNA NUCLEUS New protein CYTOPLASM

Inactive protein kinase 1 Figure 11.10 Inactive protein kinase 1 Active protein kinase 1 Inactive protein kinase 2 ATP ADP Active protein kinase 2 P PP P i Figure 11.10 A phosphorylation cascade. Inactive protein kinase 3 ATP ADP P Active protein kinase 3 PP P i ATP ADP P PP P i

Figure 11.11 Adenylyl cyclase Phosphodiesterase AMP P i ATP cAMP AMP Figure 11.11 Cyclic AMP.

G protein-coupled receptor GTP Figure 11.12 G protein G protein-coupled receptor GTP ATP cAMP Figure 11.12 cAMP as a second messenger in a G protein signaling pathway. Protein kinase A

Wild type (with shmoos) Fus3 formin CONCLUSION Figure 11.17 RESULTS Wild type (with shmoos) Fus3 formin CONCLUSION 1 G protein-coupled receptor Formin P Fus3 Actin subunit GTP P GDP 2 Formin Formin Figure 11.17 Inquiry: How do signals induce directional cell growth during mating in yeast? P 4 Microfilament Fus3 Fus3 P 5 3

Mitochondrion Active Ced-4 Active Ced-3 Other proteases Ced-4 Ced-3 Figure 11.21 Mitochondrion Active Ced-4 Active Ced-3 Other proteases Ced-4 Ced-3 Nucleases Figure 11.21 Molecular basis of apoptosis in C. elegans. (a) No death signal (b) Death signal

Cells undergoing apoptosis Figure 11.22 Cells undergoing apoptosis Space between digits 1 mm Interdigital tissue Figure 11.22 Effect of apoptosis during paw development in the mouse.