What is the target for CaMKII?

Phosphorylation is a fundamental mechanism for biological systems to rapidly change the rate or function of many types of molecules (ie, proteins and lipids). Ion channel proteins and Ca2+ homeostatic proteins involved in excitation-contraction coupling are CaMKII targets of immediate importance to arrhythmias.

Is CaMKII a transcription factor?

As we know now, CaMKII is involved in the regulation of many transcription factors such as the activation protein-1 (AP-1) (Antoine et al., 1996), activating transcription factor-1 (ATF-1) (Shimomura et al., 1996), serum response factor (SRF) (Fluck et al., 2000), cAMP-response element binding protein (CREB) (Sun et al …

What diseases might happen when there is hyperactivity of the CaMKII?

Hyperactivity of CaMKII is an established contributor to pathological cardiac remodeling, and is widely thought to directly promote arrhythmia and contractile dysfunction during HF.

What second messenger is bound by calmodulin?

Calcium
Calcium participates in an intracellular signaling system by acting as a diffusible second messenger to the initial stimuli. It does this by binding various targets in the cell including a large number of enzymes, ion channels, aquaporins and other proteins.

How is calcium regulated in cardiomyocytes?

Calcium homeostasis in cardiomyocytes is characterized by continuous waves of intracellular Ca2+ traversing the cytoplasm every second, thereby enabling muscle contraction regulated by synchronous RyR opening (4). Given this unrelenting activity, cardiomyocytes rely on mitochondria for continuous ATP production.

What are the two most common types of second messengers?

Second Messengers

• Calcium. The calcium ion (Ca2+) is perhaps the most common intracellular messenger in neurons.
• Cyclic nucleotides.
• Diacylglycerol and IP3.
• Nitric oxide.

Why is Ca2 a second messenger?

Calcium ion (Ca(2+)) plays an important role in stimulus-response reactions of cells as a second messenger. This is done by keeping cytoplasmic Ca(2+) concentration low at rest and by mobilizing Ca(2+) in response to stimulus, which in turn activates the cellular reaction.

What does calcium do to cardiac muscle?

Calcium particles enter the heart muscle cells during each heartbeat and contribute to the electrical signal that coordinates the heart’s function. Calcium particles also bind to machinery within the cell that helps the cell to squeeze together (“contract”), which makes the heart pump blood.

Which channel is most important in the release of calcium after depolarization of the cardiac muscle cell?

L-type channels
Most of this calcium enters through the L-type channels, located primarily at sarcolemmal/sarcoplasmic reticulum junctions. The influx of calcium triggers the release of further calcium from the sarcoplasmic reticulum via ryanodine receptors.

What are second messengers give examples?

Examples of second messenger molecules include cyclic AMP, cyclic GMP, inositol triphosphate, diacylglycerol, and calcium. First messengers are extracellular factors, often hormones or neurotransmitters, such as epinephrine, growth hormone, and serotonin.

Why is CA2 a second messenger?

What is one quality of a good second messenger?

The levels of second messengers are exquisitely controlled temporally and spatially, and, during signaling, enzymatic reactions or opening of ion channels ensure that they are highly amplified.

How many subunits are there in the CAMKII protein?

CaMKII is a holoenzyme composed of 12 subunits of 56–60 kDa that are assembled into 2 rings of 6 subunits each ( Gaertner et al., 2004 ). Interestingly, these subunits are proteins encoded by four distinct but highly related genes termed camk2a, camk2b, camk2d, and camk2g, which give rise to four different CaMKII isoforms: α, β, δ, and γ.

What are the roles of protein kinase A and CaMKII?

Protein kinase A and CaMKII pathways play important opposing roles in skeletal muscle gene expression by oppositely affecting the subcellular localization of HDAC4. This study demonistrated that the CaMKIIalpha expression in the brain in mice.

How is CaMKII related to Ca2 + / calmodulin complex?

Ca2+ /calmodulin-dependent protein kinase II ( CaM kinase II or CaMKII) is a serine/threonine-specific protein kinase that is regulated by the Ca2+ / calmodulin complex. CaMKII is involved in many signaling cascades and is thought to be an important mediator of learning and memory.

How are CAMKII alpha and beta subunits regulated?

Four distinct isoforms of CAMKII were isolated. Two of them were characterized as CaMKII alpha and beta subunits.CaMKII expression is developmentally regulated in human fetal and adult brain novel mechanism for Ca2+-dependent negative-feedback regulation of NR2B-containing NMDARs in a CaMKII activity-…