PLC beta 3 Gq: Difference between revisions
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'''Overview of the PLC- β3 and Gq interface:''' | '''Overview of the PLC- β3 and Gq interface:''' | ||
The Gαq subunit consists two domains, one is the GTPase domain and the other is the alpha helical domain. These domains include three regions called <scene name='70/701452/Fig2/6'>switch regions I-III</scene>. | The Gαq subunit consists two domains, one is the GTPase domain and the other is the alpha helical domain. These domains include three regions called <scene name='70/701452/Fig2/6'>switch regions I-III</scene>.These regions allows the Gαq to be released from the receptor and activate distinct downstream effectos, with a central effector being the PLC-β3 enzyme. The switch regions I and II interact with several domains in PLC-β3. | ||
<scene name='70/701452/Fig1/9'>The PLC- β3 has several domains</scene> consisting of N-terminal PH domain, a series of four EF hands, a catalytic TIM barrel that the X/Y linker connect its two halves and a C2 domain. | <scene name='70/701452/Fig1/9'>The PLC- β3 has several domains</scene> consisting of N-terminal PH domain, a series of four EF hands, a catalytic TIM barrel that the X/Y linker connect its two halves and a C2 domain. | ||
PLC- β3 engages Gαq throughout three regions. First, an extended loop between the third and fourth EF hands of PLC- β3 directly supports switch residues critical for GTP hydrolysis by Gαq. Second, the region of PLC- β3 that connects the catalytic TIM barrel and the C2 domain interacts with both switches 1 and 2 of Gαq. Third, a segment composed of a helix-turn-helix at the C terminus of the C2 domain mostly located within a shallow declivity on the surface of Gαq formed by switch 2 and α3. | PLC- β3 engages Gαq throughout three regions. First, an extended loop between the third and fourth EF hands of PLC- β3 directly supports switch residues critical for GTP hydrolysis by Gαq. Second, the region of PLC- β3 that connects the catalytic TIM barrel and the C2 domain interacts with both switches 1 and 2 of Gαq. Third, a segment composed of a helix-turn-helix at the C terminus of the C2 domain mostly located within a shallow declivity on the surface of Gαq formed by switch 2 and α3. | ||
'''Local motifs in Gq-PLC interactions:''' | |||
PLC-β3 interacts with a surface on Gαq that <scene name='70/701452/Fig5/4'>overlaps almost completely</scene> with portions of Gα subunits needed for engagement of RGS proteins and the effector-binding region. Other effectors are known to engage the <scene name='70/701452/Fig3/3'>effector-binding site</scene> within Gα subunits. There are a large family of regulator of G protein signaling (RGS) proteins that independently accelerates the GTP hydrolysis in the <scene name='70/701452/Fig4/3'>GTPase domain</scene>. | PLC-β3 interacts with a surface on Gαq that <scene name='70/701452/Fig5/4'>overlaps almost completely</scene> with portions of Gα subunits needed for engagement of RGS proteins and the effector-binding region. Other effectors are known to engage the <scene name='70/701452/Fig3/3'>effector-binding site</scene> within Gα subunits. There are a large family of regulator of G protein signaling (RGS) proteins that independently accelerates the GTP hydrolysis in the <scene name='70/701452/Fig4/3'>GTPase domain</scene>. | ||