User:MichelleMaglio/Michelle

Proposal

G-protein-gated ion channels

We will begin our discussion of g-protein-gated ion channels with a brief introduction about how g-proteins function at the molecular level. This will be followed by a brief explanation of how the structures of these proteins are useful in performing the specific functions of the ion channels they associate with. We will discuss which ions g-protein-gated ion channels are associated with (i.e. Ca2+ and K+) and the functions of those ion channels. G-proteins normally elicit cellular responses by beginning signaling pathways. However, they are also thought to directly interact with ion channels by regulating their opening and closing. This is the working hypothesis of much ongoing research involving g-proteins and ion channels. We will describe any mechanisms of g-protein-gated ion channels if any have been found (and are accessible). We will conclude our article by briefly discussing why studying g-protein-gated ion channels is relevant. For instance, their malfunction has been linked with the development of epilepsy.

Rough Outline of Article

Introduction - what g-proteins are (include link to g-proteins page) - what ion channels are and what a g-protein gated ion channel would be.

Overview of Function(s) - g-protein-gated ion channels serve a variety of functions - important role in controlling membrane excitability in the heart and brain by regulating K+ conductance (g-protein-gated inwardly rectifying K+ family of proteins). - comparison of g-protein-gated ion channels and non-g-protein gated ion channels.

Mechanisms - Binding of GDP to G-protein - Signaling pathways and direct regulation of activated g-protein subunits with ion channels. - Proposed mechanisms, possible feedback cycles, extracellular signals that may affect the g-proteins and/or ion channels.

Importance - why they are worth studying (i.e. correlation to diseases)

Division of Work: We will each read all of the material we find in our research (some of which is listed below) and write each section of the report in groups of at least two in order to maintain flow and maximize input.

List of Sources:

A G protein directly regulates mammalian cardiac calcium channels http://www.sciencemag.org/cgi/content/abstract/238/4831/1288

Molecular and Cellular Diversity of Neuronal G-Protein-Gated Potassium Channels http://www.jneurosci.org/cgi/content/full/25/49/11468

Functional expression and characterization of G-protein-gated inwardly rectifying http://www.ionchannels.org/showabstract.php?pmid=10341034

G-protein-gated inwardly rectifying K+ channels… http://bloodjournal.hematologylibrary.org/cgi/reprint/108/9/3027.pdf

Signaling via the G-protein-activated K+ channels http://www.ncbi.nlm.nih.gov/pubmed/9429760?ordinalpos=1&itool=EntrezSystem2.PEntrez.Pubmed.Pubmed_ResultsPanel.Pubmed_DiscoveryPanel.Pubmed_Discovery_RA&linkpos=4&log$=relatedreviews&logdbfrom=pubmed

Berg, Jeremy. Biochemistry. 6th ed. W.H. Freeman and Co. New York, New York. 2007.