In: Biology
What are the differences between IRKs and GIRKs, functionally and structurally? Where in the body are they found?
Answer)
IRKs | GIRKs |
IRKs refer to Inward rectifier Potassium chanels | GIRKs refer to G Protein coupled inwardly rectifiying potassium channels |
These are voltage gated and flanks transmembrne proteins | These comes under the family of ligand inward rectifier potassium channels |
Structurally,this is made up of 333 amino acyl residues with N terminal flanking P loop. These are activated by PIP2 i.e. Phosphatidyl ionositol bisphosphate | Structurally, these are made up of complex of ligand stimulation by GPCR and PIP2. They possess heteromeric complex of beta gamma subunits.They possess subunits GIRK1,2,3,4 |
Functions:-They helps in transportation of potassium ions with potassium uptake | Functions:-These are permeable to potassium ions and helps in hyperpolarization of cell membrane |
IRKs are found in cardiac muscle cells,macrophages and neurons whereas GIRKs are found in central nervous sytem and primarly heart and controls the excitability of neurons.