fbpx
Wikipedia

CAMK

CAMK, also written as CaMK or CCaMK, is an abbreviation for the Ca2+/calmodulin-dependent protein kinase class of enzymes. CAMKs are activated by increases in the concentration of intracellular calcium ions (Ca2+) and calmodulin. When activated, the enzymes transfer phosphates from ATP to defined serine or threonine residues in other proteins, so they are serine/threonine-specific protein kinases. Activated CAMK is involved in the phosphorylation of transcription factors and therefore, in the regulation of expression of responding genes. CAMK also works to regulate the cell life cycle (i.e. programmed cell death), rearrangement of the cell's cytoskeletal network, and mechanisms involved in the learning and memory of an organism.[1]

Ca2+/calmodulin-dependent protein kinase
Identifiers
EC no.2.7.11.17
CAS no.97350-82-8
Databases
IntEnzIntEnz view
BRENDABRENDA entry
ExPASyNiceZyme view
KEGGKEGG entry
MetaCycmetabolic pathway
PRIAMprofile
PDB structuresRCSB PDB PDBe PDBsum
Gene OntologyAmiGO / QuickGO
Search
PMCarticles
PubMedarticles
NCBIproteins

Types edit

There are 2 common types of CAM Kinase proteins: specialized and multi-functional CAM kinases.

Substrate-specific CAM Kinases
only have one target that they can phosphorylate, such as myosin light chain kinases.[1] This group of proteins includes CAMK III. More on CAMKIII can be found following this link.
Multi-functional CAM Kinases
have multiple targets they can phosphorylate and are found in processes including the secretion of neurotransmitters, metabolism of glycogen, and the regulation of various transcription factors.[1] CAMK II is the main protein in this subset. More on CAMKII can be found following this link.

Substrate phosphorylation edit

 
Figure 1: Diagram of how CAMK II becomes active in the presence of calcium or calmodulin.

Once calcium concentrations in the cell rise, CAM kinases become saturated and bind the maximum of four calcium molecules.[1] This calcium saturation activates the kinase and allows it to undergo a conformational change which permits the kinase to bind to its phosphorylation target sites. CAMK removes a phosphate group from ATP, most typically using a Mg2+ ion, and adds it to the CAM protein, rendering it active.[2] The CAM Kinase contains a highly concentrated glycine loop where the gamma phosphate from the donor ATP molecule is easily able to bind to the enzyme which then utilizes the metal ion to facilitate a smooth phosphate transfer to the target protein.[3] This phosphate transfer then activates the kinase's target and completes the phosphorylation cycle.

Figure 1 shows how the presence of calcium or calmodulin allows for the activation of CAM kinases (CAMK II).

 
Figure 2: Graphic illustration of the crude domains of Calcium/calmodulin-dependent protein kinase 1[1]

Structure edit

All kinases have a common structure of a catalytic core including an ATP binding site along with a larger substrate binding site.[4] The catalytic core is typically composed of β-strands with the substrate binding site composed of α-helices.[5] Most all CAM kinases includes a variety of domains, including: a catalytic domain, a regulatory domain, an association domain, and a calcium/calmodulin binding domain.[6]

CAMK I
as shown in Figure 2, has a double-lobed structure, consisting of a catalytic, substrate-binding domain and an autoinhibitory domain.[1] For the autoinhibitory domain to become functional, it must cause the protein to conform in such a way that this domain completely blocks the substrate domain from taking in new targets. Figure 2 goes into detail showing the structure and domains of CAMK I.
CAMK II
has a variety of different forms, with CAMK 2A being the most common, as shown in Figure 3. CAMK 2A has a ring-like crystalline structure, composed of smaller functional groups. These groups allow for the CaM-dependent phosphorylation of targets, but also allows the structure to autophosphorylate itself and become CaM-independent,[7] as seen in Figure 1. This means once the CAMK 2A protein is initially activated by calcium or calmodulin, it can, in turn, further activate itself, so it doesn't become inactive even when it is without calcium or calmodulin.
 
Figure 3: Image of CAMK 2A which is a form of Calcium/calmodulin-dependent kinase in its crystalline form.

Family members edit

Members of the CAMK enzyme class include, but are not limited to:

Pseudokinases edit

Pseudokinases are pseudoenzymes, proteins that resemble enzymes structurally, but lack catalytic activity.

Some of these pseudokinases that are related to the CAMK family include:

References edit

  1. ^ a b c d e f Swulius MT, Waxham MN (September 2008). "Ca(2+)/calmodulin-dependent protein kinases". Cellular and Molecular Life Sciences. 65 (17): 2637–57. doi:10.1007/s00018-008-8086-2. PMC 3617042. PMID 18463790.
  2. ^ Adams JA (August 2001). "Kinetic and catalytic mechanisms of protein kinases". Chemical Reviews. 101 (8): 2271–90. doi:10.1021/cr000230w. PMID 11749373.
  3. ^ Hemmer W, McGlone M, Tsigelny I, Taylor SS (July 1997). "Role of the glycine triad in the ATP-binding site of cAMP-dependent protein kinase". The Journal of Biological Chemistry. 272 (27): 16946–54. doi:10.1074/jbc.272.27.16946. PMID 9202006. S2CID 33795382.
  4. ^ Hanks SK (2003). "Genomic analysis of the eukaryotic protein kinase superfamily: a perspective". Genome Biology. 4 (5): 111. doi:10.1186/gb-2003-4-5-111. PMC 156577. PMID 12734000.{{cite journal}}: CS1 maint: unflagged free DOI (link)
  5. ^ Taylor SS, Yang J, Wu J, Haste NM, Radzio-Andzelm E, Anand G (March 2004). "PKA: a portrait of protein kinase dynamics". Biochimica et Biophysica Acta (BBA) - Proteins and Proteomics. 1697 (1–2): 259–69. doi:10.1016/j.bbapap.2003.11.029. PMID 15023366.
  6. ^ Hudmon A, Schulman H (2002-06-01). "Neuronal CA2+/calmodulin-dependent protein kinase II: the role of structure and autoregulation in cellular function". Annual Review of Biochemistry. 71 (1): 473–510. doi:10.1146/annurev.biochem.71.110601.135410. PMID 12045104.
  7. ^ "CAMK2A calcium/calmodulin dependent protein kinase II alpha [Homo sapiens (human)] - Gene - NCBI". www.ncbi.nlm.nih.gov. Retrieved 2020-03-20.

camk, also, written, camk, ccamk, abbreviation, calmodulin, dependent, protein, kinase, class, enzymes, activated, increases, concentration, intracellular, calcium, ions, calmodulin, when, activated, enzymes, transfer, phosphates, from, defined, serine, threon. CAMK also written as CaMK or CCaMK is an abbreviation for the Ca2 calmodulin dependent protein kinase class of enzymes CAMKs are activated by increases in the concentration of intracellular calcium ions Ca2 and calmodulin When activated the enzymes transfer phosphates from ATP to defined serine or threonine residues in other proteins so they are serine threonine specific protein kinases Activated CAMK is involved in the phosphorylation of transcription factors and therefore in the regulation of expression of responding genes CAMK also works to regulate the cell life cycle i e programmed cell death rearrangement of the cell s cytoskeletal network and mechanisms involved in the learning and memory of an organism 1 Ca2 calmodulin dependent protein kinaseIdentifiersEC no 2 7 11 17CAS no 97350 82 8DatabasesIntEnzIntEnz viewBRENDABRENDA entryExPASyNiceZyme viewKEGGKEGG entryMetaCycmetabolic pathwayPRIAMprofilePDB structuresRCSB PDB PDBe PDBsumGene OntologyAmiGO QuickGOSearchPMCarticlesPubMedarticlesNCBIproteins Contents 1 Types 2 Substrate phosphorylation 3 Structure 4 Family members 5 Pseudokinases 6 ReferencesTypes editThere are 2 common types of CAM Kinase proteins specialized and multi functional CAM kinases Substrate specific CAM Kinases only have one target that they can phosphorylate such as myosin light chain kinases 1 This group of proteins includes CAMK III More on CAMKIII can be found following this link Multi functional CAM Kinases have multiple targets they can phosphorylate and are found in processes including the secretion of neurotransmitters metabolism of glycogen and the regulation of various transcription factors 1 CAMK II is the main protein in this subset More on CAMKII can be found following this link Substrate phosphorylation edit nbsp Figure 1 Diagram of how CAMK II becomes active in the presence of calcium or calmodulin Once calcium concentrations in the cell rise CAM kinases become saturated and bind the maximum of four calcium molecules 1 This calcium saturation activates the kinase and allows it to undergo a conformational change which permits the kinase to bind to its phosphorylation target sites CAMK removes a phosphate group from ATP most typically using a Mg2 ion and adds it to the CAM protein rendering it active 2 The CAM Kinase contains a highly concentrated glycine loop where the gamma phosphate from the donor ATP molecule is easily able to bind to the enzyme which then utilizes the metal ion to facilitate a smooth phosphate transfer to the target protein 3 This phosphate transfer then activates the kinase s target and completes the phosphorylation cycle Figure 1 shows how the presence of calcium or calmodulin allows for the activation of CAM kinases CAMK II nbsp Figure 2 Graphic illustration of the crude domains of Calcium calmodulin dependent protein kinase 1 1 Structure editAll kinases have a common structure of a catalytic core including an ATP binding site along with a larger substrate binding site 4 The catalytic core is typically composed of b strands with the substrate binding site composed of a helices 5 Most all CAM kinases includes a variety of domains including a catalytic domain a regulatory domain an association domain and a calcium calmodulin binding domain 6 CAMK I as shown in Figure 2 has a double lobed structure consisting of a catalytic substrate binding domain and an autoinhibitory domain 1 For the autoinhibitory domain to become functional it must cause the protein to conform in such a way that this domain completely blocks the substrate domain from taking in new targets Figure 2 goes into detail showing the structure and domains of CAMK I CAMK II has a variety of different forms with CAMK 2A being the most common as shown in Figure 3 CAMK 2A has a ring like crystalline structure composed of smaller functional groups These groups allow for the CaM dependent phosphorylation of targets but also allows the structure to autophosphorylate itself and become CaM independent 7 as seen in Figure 1 This means once the CAMK 2A protein is initially activated by calcium or calmodulin it can in turn further activate itself so it doesn t become inactive even when it is without calcium or calmodulin nbsp Figure 3 Image of CAMK 2A which is a form of Calcium calmodulin dependent kinase in its crystalline form Family members editMembers of the CAMK enzyme class include but are not limited to CAMKI CAMKIa CAMK1 CAMKIb PNCK CAMKId CAMKIg CAMK1G CAMKII CAMKIIa CAMKIIb CAMKIId CAMKIIg CAMKIII CAMKIV CAMKV CaM kinase like vesicle associated SCAMK Ca2 calmodulin dependent protein kinase kinase CAMKK1 CAMKK2Pseudokinases editPseudokinases are pseudoenzymes proteins that resemble enzymes structurally but lack catalytic activity Some of these pseudokinases that are related to the CAMK family include Tribbles subfamily TRIB1 TRIB2 TRIB3References edit a b c d e f Swulius MT Waxham MN September 2008 Ca 2 calmodulin dependent protein kinases Cellular and Molecular Life Sciences 65 17 2637 57 doi 10 1007 s00018 008 8086 2 PMC 3617042 PMID 18463790 Adams JA August 2001 Kinetic and catalytic mechanisms of protein kinases Chemical Reviews 101 8 2271 90 doi 10 1021 cr000230w PMID 11749373 Hemmer W McGlone M Tsigelny I Taylor SS July 1997 Role of the glycine triad in the ATP binding site of cAMP dependent protein kinase The Journal of Biological Chemistry 272 27 16946 54 doi 10 1074 jbc 272 27 16946 PMID 9202006 S2CID 33795382 Hanks SK 2003 Genomic analysis of the eukaryotic protein kinase superfamily a perspective Genome Biology 4 5 111 doi 10 1186 gb 2003 4 5 111 PMC 156577 PMID 12734000 a href Template Cite journal html title Template Cite journal cite journal a CS1 maint unflagged free DOI link Taylor SS Yang J Wu J Haste NM Radzio Andzelm E Anand G March 2004 PKA a portrait of protein kinase dynamics Biochimica et Biophysica Acta BBA Proteins and Proteomics 1697 1 2 259 69 doi 10 1016 j bbapap 2003 11 029 PMID 15023366 Hudmon A Schulman H 2002 06 01 Neuronal CA2 calmodulin dependent protein kinase II the role of structure and autoregulation in cellular function Annual Review of Biochemistry 71 1 473 510 doi 10 1146 annurev biochem 71 110601 135410 PMID 12045104 CAMK2A calcium calmodulin dependent protein kinase II alpha Homo sapiens human Gene NCBI www ncbi nlm nih gov Retrieved 2020 03 20 Portal nbsp Biology Retrieved from https en wikipedia org w index php title CAMK amp oldid 1172341586, wikipedia, wiki, book, books, library,

article

, read, download, free, free download, mp3, video, mp4, 3gp, jpg, jpeg, gif, png, picture, music, song, movie, book, game, games.