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2nd messengers breakdown because they have great power to proceed the signalling pathway.
the pathway continue to give results until 2nd messenger level decreases in cytoplasm
e.g., cAMP is a powerful 2nd messenger and stimulates PKA (protein kinase A)
PKA proceed pathway but on the same time activates PDE3 (phospodiesterase 3)
which inactivates cAMP
if this process not happens then there is imbalance of functions
e.g., Beta 2-receptors in seminal tract act by cAMP and cause relaxation and alpha 1 receptors act by Ca++ and cause contraction. one system dominates over other at a time and vice versa. now the movement of semen is the combined effect of contractions and relaxations
if cAMP level is increased by inhibiting its break down through PDE3 tehn there will be only relaxation and semen cannot move hence failure of ejaculation.
What else can I help you with?
What do all histamine transduction pathways have in common?
Histamine transduction pathways typically involve binding of histamine to its receptors, which are G protein-coupled receptors. This binding activates downstream signaling cascades, which can involve second messengers such as cyclic AMP or calcium ions. Ultimately, these pathways lead to diverse physiological responses depending on the specific receptor subtype and cell type involved.
How are relay proteins activated?
They can be activated by signaling molecules such as second messengers.
What are possible Multiple choice questions in biochemistry related to process of signal transduction?
Which enzyme is responsible for phosphorylating target proteins in signal transduction pathways? Which second messenger is produced from the cleavage of phosphatidylinositol 4,5-bisphosphate in signal transduction? Which cell surface receptor is involved in the activation of the MAPK signaling pathway? What is the role of G proteins in signal transduction cascades?
What is a second messenger system?
A second messenger system is a signaling pathway employed by cells to transmit signals from the cell membrane to the cytoplasm or nucleus. It involves the activation of specific molecules (second messengers) in response to an initial extracellular signal, which then propagate the signal within the cell to elicit a cellular response. Common second messengers include cAMP, Ca2+, and IP3.
Do second messengers inactivate protein kinase enzymes?
No, second messengers do not inactivate protein kinase enzymes; rather, they typically activate them. Second messengers, such as cyclic AMP (cAMP) or calcium ions, facilitate the activation of protein kinases by binding to them or by modulating other regulatory proteins. This activation leads to the phosphorylation of target proteins, which is a key step in many cellular signaling pathways. Inactivation of protein kinases usually occurs through other mechanisms, such as dephosphorylation by phosphatases.
What are the roles of second messengers in signal transduction pathways?
The term second messenger was given with the discovery of chemicals that work inside the cell. Hormones and other molecules that function outside the cell are called first messengers in the transmission of information.
What Neurotransmitter receptors activate second messengers systems.?
Neurotransmitter receptors that activate second messenger systems include G protein-coupled receptors (GPCRs) and some receptor tyrosine kinases. When a neurotransmitter binds to a GPCR, it triggers a conformational change that activates intracellular G proteins, which in turn can modulate various second messengers like cyclic AMP (cAMP) and inositol triphosphate (IP3). These second messengers then initiate a cascade of cellular responses, influencing processes such as gene expression and cell signaling. Examples include dopamine, serotonin, and norepinephrine receptors.
What do all histamine transduction pathways have in common?
Histamine transduction pathways typically involve binding of histamine to its receptors, which are G protein-coupled receptors. This binding activates downstream signaling cascades, which can involve second messengers such as cyclic AMP or calcium ions. Ultimately, these pathways lead to diverse physiological responses depending on the specific receptor subtype and cell type involved.
What is a biological messenger?
Biological messengers are molecules thatÊtransmit information about cells to the receptor. They are also called neurotransmitters, first messengers, or second messengers.
What has the author D G Hardie written?
D. G. Hardie has written: 'Biochemical messengers' -- subject(s): Cell Communication, Cell receptors, Cellular signal transduction, Growth Substances, Growth factors, Hormones, Neuroregulators, Neurotransmitters, Paracrine mechanisms, Peptide hormones, Physiology, Second messengers (Biochemistry) 'Protein kinase factsbook' -- subject(s): Handbooks, manuals, Protein kinases
Which substance is called the second chemical messenger?
Cyclic AMP (cAMP) is often referred to as the second messenger in signal transduction pathways. It is a key component in mediating intracellular responses to extracellular signals such as hormones and neurotransmitters.
What are two important second messengers used in the G protein-linked receptor mechanism?
Two important second messengers are cyclic AMP (cAMP) and inositol triphosphate (IP3)/diacylglycerol (DAG). cAMP is involved in activating protein kinase A, while IP3/DAG is involved in releasing calcium from intracellular stores and activating protein kinase C. Both play crucial roles in signal transduction within the G protein-linked receptor mechanism.
Virtually all of the protein or amino acid-based hormones exert their effects through intracellular?
receptor binding, which leads to signal transduction pathways being activated within the target cell. This results in various physiological responses, such as gene expression regulation, enzyme activation, or cell growth and differentiation.
How are relay proteins activated?
They can be activated by signaling molecules such as second messengers.
What do you call the messengers in the endocrine system?
The second most important is cAMP
What does calcium ions that act as a second messengers stored in?
endoplasmic reticulum
Intracellular chemical signals known as second messengers?
Second messengers are small molecules that transmit signals inside cells, amplifying and regulating the cellular response to the original stimulus. Common examples include cAMP, calcium ions, and IP3. They are crucial in cellular communication and are involved in a wide range of signaling pathways.
