Sandbox Reserved 1167: Difference between revisions
From Proteopedia
Jump to navigationJump to search
No edit summary |
No edit summary |
||
| Line 8: | Line 8: | ||
== Background == | == Background == | ||
[[Image:7tm_labeled_with_membrane.png|200 px|left|thumb|The 7tm spans the cell membrane]]The human glucagon receptor (GCGR) is one of 15 secretin-like, or Class B, G-protein-coupled receptors (GPCRs). Like other GPCRs, it has a <scene name='72/721538/7tm_labeled_helicies/3'>7 trans-membrane </scene> helical domain (shown in blue) and a globular N-terminus <scene name='72/721538/Ecd/2'>extracellular domain</scene> (shown in magenta). As its name suggests, the 7tm is made up of alpha helices that pass through the membrane seven times. The extracellular domain has an α-β-β structure that consists of two antiparallel β-sheets and a N-terminal α-helix<ref>PMID:26227798</ref>. | [[Image:7tm_labeled_with_membrane.png|200 px|left|thumb|The 7tm spans the cell membrane]]The human glucagon receptor (GCGR) is one of 15 secretin-like, or Class B, G-protein-coupled receptors (GPCRs). Like other GPCRs, it has a <scene name='72/721538/7tm_labeled_helicies/3'>7 trans-membrane </scene> helical domain (shown in blue) and a globular N-terminus <scene name='72/721538/Ecd/2'>extracellular domain</scene> (shown in magenta). As its name suggests, the 7tm is made up of alpha helices that pass through the membrane seven times. The extracellular domain has an α-β-β structure that consists of two antiparallel β-sheets and a N-terminal α-helix<ref>PMID:26227798</ref>. | ||
== Function == | == Function == | ||
The Glucagon Receptor plays an important role in glucose homeostasis. During times of fasting (or low blood sugar) the pancreas dispatches glucagon to activate the GCGR in the liver. The [http://www.nature.com/nature/journal/v499/n7459/fig_tab/nature12393_F5.html binding of glucagon] stimulates gluconeogenesis, through adenylate cyclase that initiates protein kinase A (PKA) activity<ref>PMID:25674162</ref>. This pathway synthesizes glucose, elevating blood sugar levels. | The Glucagon Receptor plays an important role in glucose homeostasis. During times of fasting (or low blood sugar) the pancreas dispatches glucagon to activate the GCGR in the liver. The [http://www.nature.com/nature/journal/v499/n7459/fig_tab/nature12393_F5.html binding of glucagon] stimulates gluconeogenesis, through adenylate cyclase that initiates protein kinase A (PKA) activity<ref>PMID:25674162</ref>. This pathway synthesizes glucose, elevating blood sugar levels. | ||
== Structure == | == Structure == | ||
| Line 26: | Line 24: | ||
As a part of the interface stabilization between helices VI, V, and III, a Class B specific [https://en.wikipedia.org/wiki/Hydrogen_bond hydrogen bond] occurs between [https://en.wikipedia.org/wiki/Asparagine N] 318 of Helix V and [https://en.wikipedia.org/wiki/Leucine L] 242 of Helix III. | As a part of the interface stabilization between helices VI, V, and III, a Class B specific [https://en.wikipedia.org/wiki/Hydrogen_bond hydrogen bond] occurs between [https://en.wikipedia.org/wiki/Asparagine N] 318 of Helix V and [https://en.wikipedia.org/wiki/Leucine L] 242 of Helix III. | ||
=== GCGR-Specific Traits === | === GCGR-Specific Traits === | ||
| Line 43: | Line 40: | ||
An important interface stabilization interaction between helices I and VII occurs between [https://en.wikipedia.org/wiki/Serine Ser] 152 of Helix I and Ser 390 of Helix VII. Due to their close proximity to one another, they form an important <scene name='72/721537/Ser-ser_hydrogen_bond/2'>hydrogen bond</scene> which stabilizes the structure of GCGR. | An important interface stabilization interaction between helices I and VII occurs between [https://en.wikipedia.org/wiki/Serine Ser] 152 of Helix I and Ser 390 of Helix VII. Due to their close proximity to one another, they form an important <scene name='72/721537/Ser-ser_hydrogen_bond/2'>hydrogen bond</scene> which stabilizes the structure of GCGR. | ||
== Glucagon Binding == | == Glucagon Binding == | ||
