Sandbox Reserved 1723: Difference between revisions

From Proteopedia
Jump to navigationJump to search
No edit summary
No edit summary
Line 64: Line 64:


[[Image:Gq_and_Gi_snip.PNG|300px|right|thumb|'''Figure 4''': Caption.<ref name="Cao"/>]]
[[Image:Gq_and_Gi_snip.PNG|300px|right|thumb|'''Figure 4''': Caption.<ref name="Cao"/>]]
Once the ligand is bound, MRGPRX2 undergoes a conformational change that is transmitted through to the [https://en.wikipedia.org/wiki/G_protein#:~:text=G%20proteins%2C%20also%20known%20as,a%20cell%20to%20its%20interior. G-protein]. This conformational change is affected by the aforementioned deviances from Class A GPCRs. Rather than a large conformational change, a subtle one is induced. This will allow MRGPRX2 to interact with a G-protein. <scene name='90/904327/Gproteins/2'>G-proteins</scene> are composed of 3 subunits; α, β, and γ. When activated, the receptor acts as a Guanine nucleotide factor (GEF) which will allow the Gα subunit to have its GDP be replaced by a GTP. This will cause the Gα subunit to dissociate from the dimer Gβγ. The Gα subunit is then able to act as a secondary messenger to begin the signal transduction in the cell. MRGPRX2 interacts with two different types of G-proteins; Gi and Gq. These G-proteins are activated by similar interactions with the receptor however, they are structurally different and changes in the induced conformation are observed (Figure 6). Due to these structural differences, differences in ligand binding to MRGPRX2 bound to Gi in comparison to Gq are observed (Figure 5).   
Once the ligand is bound, MRGPRX2 undergoes a conformational change that is transmitted through to the [https://en.wikipedia.org/wiki/G_protein#:~:text=G%20proteins%2C%20also%20known%20as,a%20cell%20to%20its%20interior. G-protein]. This conformational change is affected by the aforementioned deviances from Class A GPCRs. Rather than a large conformational change, a subtle one is induced. This will allow MRGPRX2 to interact with a G-protein. <scene name='90/904327/Gproteins/2'>G-proteins</scene> are composed of 3 subunits; α, β, and γ. When activated, the receptor acts as a Guanine nucleotide factor (GEF) which will allow the Gα subunit to have its GDP be replaced by a GTP. This will cause the Gα subunit to dissociate from the dimer Gβγ. The Gα subunit is then able to act as a secondary messenger to begin the signal transduction in the cell. MRGPRX2 interacts with two different types of G-proteins; Gi and Gq. These G-proteins are activated by similar interactions with the receptor however, they are structurally different and changes in the induced conformation are observed (Figure 4). Due to these structural differences, differences in ligand binding to MRGPRX2 bound to Gi in comparison to Gq are observed (Figure 5).   
[[Image:GqGi_with_zincs_snip.PNG|300px|left|thumb|'''Figure 5''': Caption.<ref name="Cao"/>]]
[[Image:GqGi_with_zincs_snip.PNG|300px|left|thumb|'''Figure 5''': Caption.<ref name="Cao"/>]]