24 Second messengers Questions What is a second messenger? What are the necessary properties of a second messenger? How do second messengers activate intracellular signalling pathways? Activation of many receptors results in cascades of intracellular cell signalling events initiated through transducing proteins, intracellular (second) messengers and effector enzymes. Characteristics of second messengers In many instances, the response to receptor activation is activation of an enzyme effector, which produces a small intracellular messenger molecule or ‘second messenger’. So that intracellular signalling occurs only during receptor activation, second messengers must: be maintained at low concentration in the resting cell be produced only in response to activation of specific receptors be produced in proportion to the size of the extracellular signal produce a cellular response in proportion to the change in concentration of the second messenger be degraded rapidly to ensure transience in signalling pathways. Cyclic nucleotides Cyclic adenosine 3′,5′-monophosphate (cyclic AMP; Fig. 3.24.1) is produced by an integral plasma membrane enzyme, adenylyl cyclase 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 Second messengers Full access? Get Clinical Tree
24 Second messengers Questions What is a second messenger? What are the necessary properties of a second messenger? How do second messengers activate intracellular signalling pathways? Activation of many receptors results in cascades of intracellular cell signalling events initiated through transducing proteins, intracellular (second) messengers and effector enzymes. Characteristics of second messengers In many instances, the response to receptor activation is activation of an enzyme effector, which produces a small intracellular messenger molecule or ‘second messenger’. So that intracellular signalling occurs only during receptor activation, second messengers must: be maintained at low concentration in the resting cell be produced only in response to activation of specific receptors be produced in proportion to the size of the extracellular signal produce a cellular response in proportion to the change in concentration of the second messenger be degraded rapidly to ensure transience in signalling pathways. Cyclic nucleotides Cyclic adenosine 3′,5′-monophosphate (cyclic AMP; Fig. 3.24.1) is produced by an integral plasma membrane enzyme, adenylyl cyclase 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 Second messengers Full access? Get Clinical Tree
