• Second messengers are intracellular signaling
molecules released by the cell to trigger physiological
changes such as proliferation, differentiation, migration,
survival, and apoptosis.
• Secondary messengers are therefore one of the
initiating components of intracellular signal transduction
4. Mechanism of second messenger
• Electrical and biochemical
signals are stimulated by the
second messenger mechanism.
• These signals are stable long-
lasting and specialized for
memory. The human brain
uses calcium and adenosine
successfully transfer the
synaptic stimulus which is
stored in the brain.
• The first messenger is no need
for entering the cell because of
the fast response with neurons
• These are amplifiers for the
primary as well as multiple
signaling pathways at different
places of the cell.
11. Di acyalglycrol
• Diaclyglysrol stimulate protein
kinase C activity by increasing
the affinity of enzyme for
• Protein kinase C phosphorylates
serine and threonine residues in
12. Calcium ion
• Act as second messenger in many
• First bind to an effector molecule
• Secondly bind to calmodiulin
13. Nitric oxide
• Nitric oxide also known
• Arginine and oxygen
• Activates the guanylyl
• High concentrations
• The second messenger plays a vital role in cell signaling of intracellular
• These transduction pathways allow responding to environmental messages.
• These are creating relation communication and interaction with other cells.
• In which cyclic AMP, cyclic GMP, nitric oxide and calcium which performs
special function these activate the protein receptors which transfer the
• It shows transduction in the cell membrane and cytoplasm. Second
messenger coupled as downstream bind with first messenger and response
to their need.
• So these are work as amplifiers in the physical and chemicals response of the
• These play a vital role in phosphorylation
• Kodis EJ, Smindak RJ, Kefauver JM, Heffner DL, Aschenbach KL,
Brennan ER, Chan K, Gamage KK, Lambeth PS, Lawler JR, Sikora
AK (May 2001).
• "First Messengers". eLS. Chichester: John Wiley & Sons
Ltd. doi:10.1002/9780470015902.a0024167. ISBN 978-
0470016176. Yoshida Y, Imai S (June 1997). "Structure and function
of inositol 1,4,5-trisphosphate receptor". Japanese Journal of
Pharmacology. 74(2): 125–
37. doi:10.1254/jjp.74.125. PMID 9243320.
• ^ Purves D, Augustine GL, Fitzpatrick D, Katz LC, LaMantia AS,
McNamara JO, Williams SM, eds. (2001).
• "Chapter 8: Intracellular Signal Transduction: Second
Messengers". Neuroscience (2nd ed.). Sinauer
Associates. ISBN 978-0-87893-7