Lecture 8 - Cell Communication (Fitch) 10-1

Lecture 8 - Cell Communication (Fitch) 10-1 - Cell...

Info iconThis preview shows pages 1–8. Sign up to view the full content.

View Full Document Right Arrow Icon
Cell Communication Principles of Biology Lecture 8 Prof. David Fitch
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Principles of cell communication Cells coordinate and organize activity by communicating Communication is via signal molecules Cell communication is ancient Communication can be local or long distance Communication involves both “talking” and “listening,” i.e., both signal and response
Background image of page 2
Communication via diffusible signals α factor Receptor Exchange of mating factors. Each cell type secretes a mating factor that binds to receptors on the other cell type. Mating. Binding of the factors to receptors induces changes in the cells that lead to their fusion. New a/ α cell. The nucleus of the fused cell includes all the genes from the a and α cells. α factor Yeast cell, mating type a Yeast cell, mating type α α α a/ α a a 1 3 2
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Communication via direct contact Plasma membranes (a) Cell junctions. Both animals and plants have cell junctions that allow molecules to pass readily between adjacent cells without crossing plasma membranes. (b) Cell-cell recognition. Two cells in an animal may communicate by interaction between molecules protruding from their surfaces. Plasmodesmata between plant cells Gap junctions between animal cells
Background image of page 4
Signaling can be local or long-distance (a) Paracrine signaling. A secreting cell acts on nearby target cells by discharging molecules of a local regulator (a growth factor, for example) into the extracellular fluid. (b) Synaptic signaling. A nerve cell releases neurotransmitter molecules into a synapse, stimulating the target cell. Hormone travels in bloodstream to target cells (c) Hormonal signaling. Specialized endocrine cells secrete hormones into body fluids, often the blood. Hormones may reach virtually all body cells. Local regulator diffuses through extracellular fluid Secreting cell Target cell Secretory vesicle Electrical signal along nerve cell triggers release of neurotransmitter Neurotransmitter diffuses across synapse Target cell is stimulated Local signaling Long-distance signaling Endocrine cell Blood vessel Target cell
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Cell communication basics Cells coordinate and organize activity by communicating (mating, cell growth, neural activity) Communication is via signal molecules (mating factors, growth factors, hormones, neurotransmitters) Cell communication is ancient (conserved components indicate shared evolutionary history) Not simply that yeast cells are “primitive”, but that shared components indicate shared genetic history. Communication can be local or long distance Communication involves both “talking” and “listening,” i.e., both signal and response
Background image of page 6
Example: steroid hormone signaling leads to effects on somatic sexual development Hormone (testosterone) EXTRACELLULAR FLUID Receptor protein Plasma membrane Hormone- receptor complex DNA mRNA NUCLEUS CYTOPLASM New protein The steroid hormone testosterone passes through the plasma membrane. 1
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 8
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 04/29/2008 for the course BIO V23.0011 taught by Professor Fitch during the Spring '08 term at NYU.

Page1 / 39

Lecture 8 - Cell Communication (Fitch) 10-1 - Cell...

This preview shows document pages 1 - 8. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online