4.2 Signal Transduction
Signal Transduction pathways differ in specific details, but have certain, unifying characteristics. All pathways follow a sequence: Reception，Transduction, Response
To Think About:
What is a signal transduction pathway? Why do cells use signal transduction pathways? How does a signal transduction pathway begin? What is the role of protein modification in signal transduction pathways? What is the role of phosphorylation cascades in signal transduction pathways? What role does the environment play in eliciting cellular responses? How are signal transduction pathways used to influence cellular responses when there are changes in the environment?
Watch: AP Daily Video Introduction to Signal Transduction
Answer the Following Questions:
- Signal transduction pathways link ____________________ to ______________
- The three steps in all signal transduction pathways are ________________, ___________________________ and ____________________
- What is reception?
- What is transduction?
- What is response?
- Many signal transduction pathways include protein __________ and ___________ _______________ Examples of this include: a. Regulating protein synthesis by ________________ in the nucleus b. Regulating activity of proteins in the ________________ c. ________________ of molecular interactions that send signals from receptors to ____________ ___________________ d. Phosphorylation cascades that ______________________________________
- Key to the binding of a ligand to a receptor is ______________________
- When a ligand binds to a G-protein coupled receptor, GDP is converted into _________, this then can activate other proteins in the cell (the example shows the protein ____________ ______________ being activated)
- Signaling cascades can ___________________ signals, increasing the effect of the ligand.
- cAMP (cyclic AMP) is an example of a __________________ messenger
- When the ligand binds, the intracellular (inside the cell) domain of the receptor protein changes ___________, which starts the ___________________ of the signal.
- Ligand-gated ion channels may _____________ or ___________ when the ligand binds.
- Draw the picture showing the difference between the protein ligand signal transduction pathway and the steroid ligand signal transduction pathway.
- What is the major difference between the protein and steroid signal transduction pathway?
- In the multiple choice question at the end of the video, what describes the role of metfomin in the signal transduction pathway?
Watch: AP Daily Video Signal Transduction
Answer the Following Questions:
- Signal transduction pathways are important because they allow cells to respond to changes in their ____________________
- In the example with epinephrine, the binding of epinephrine to its ___________ ultimately leads to the breakdown of __________________ leading to increased levels of ______________ being available to the cell.
- Signaling pathways that target gene expression can alter the amount or types of _____________________ in a cell.
- Programmed cell death (also known as ____________________) can also be a result of signal transduction
- _____________ _____________________ allows bacteria to detect changes in population density.
- Why would some cells respond to the ligand epinephrine while other cells do not?
Supplementary Resources:
- Bozeman Science: Mr. Andersen’s “Signal Transduction Pathways” video
University of Utah: Learn.Genetics - The Glycogenolysis Signaling Cascade
Nobel Prize in Physiology and Medicine, 1994: Alfred Gilman, Martin Rodbell, “for their discovery of G-proteins and the role of these proteins in signal transduction in cells.”
Nobel Prize in Physiology and Medicine, 1998: Louis Ignarro, Robert Furchgott, and Ferid Murad, “for their discoveries concerning nitric oxide as a signaling molecule in the cardiovascular system.”
Nobel Prize in Physiology and Medicine, 2000: Arvid Carlsson, Paul Greengard, and Eric Kandel, “for their discoveries concerning signal transduction in the nervous system.”
