22 Signal transduction by receptors Questions How are receptor subtypes defined pharmacologically? How may ligand–receptor interactions result in cellular responses? Why may the time for signal transduction be different for different receptors? Classification of receptors Receptors are classified according to the specific physiological signalling molecule (agonist) that they recognize (e.g. acetylcholine receptors). Further subclassification is made on the basis of their ability to be selectively activated by agonist molecules (e.g. nicotinic and muscarinic acetylcholine receptors). Subclassification is also often made on the basis of the affinity (a measure of tightness of binding) of a series of antagonists. Signal transduction by receptors Common mechanisms used to transduce an extracellular signal into an intracellular event include: membrane-bound receptors with integral ion channels: ligand-gated ion channels (Fig. 3.22.1A) membrane-bound receptors with integral enzyme activity (Fig. 3.22.1B and 3.22.2) membrane-bound receptors coupled to G-proteins (Fig. 3.22.1C) intracellular receptors. Fig. 3.22.1 Only gold members can continue reading. Log In or Register to continue Share this:Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window)Like this:Like Loading... Related Related posts: DNA and gene transcription Ion transporters in cellular physiology The extracellular matrix Proteins and protein function Stay updated, free articles. Join our Telegram channel Join Tags: The Flesh and Bones of Medical Cell Biology Jun 18, 2016 | Posted by admin in BIOCHEMISTRY | Comments Off on Signal transduction by receptors Full access? Get Clinical Tree
22 Signal transduction by receptors Questions How are receptor subtypes defined pharmacologically? How may ligand–receptor interactions result in cellular responses? Why may the time for signal transduction be different for different receptors? Classification of receptors Receptors are classified according to the specific physiological signalling molecule (agonist) that they recognize (e.g. acetylcholine receptors). Further subclassification is made on the basis of their ability to be selectively activated by agonist molecules (e.g. nicotinic and muscarinic acetylcholine receptors). Subclassification is also often made on the basis of the affinity (a measure of tightness of binding) of a series of antagonists. Signal transduction by receptors Common mechanisms used to transduce an extracellular signal into an intracellular event include: membrane-bound receptors with integral ion channels: ligand-gated ion channels (Fig. 3.22.1A) membrane-bound receptors with integral enzyme activity (Fig. 3.22.1B and 3.22.2) membrane-bound receptors coupled to G-proteins (Fig. 3.22.1C) intracellular receptors. Fig. 3.22.1 Only gold members can continue reading. Log In or Register to continue Share this:Click to share on Twitter (Opens in new window)Click to share on Facebook (Opens in new window)Like this:Like Loading... Related Related posts: DNA and gene transcription Ion transporters in cellular physiology The extracellular matrix Proteins and protein function Stay updated, free articles. Join our Telegram channel Join Tags: The Flesh and Bones of Medical Cell Biology Jun 18, 2016 | Posted by admin in BIOCHEMISTRY | Comments Off on Signal transduction by receptors Full access? Get Clinical Tree
