Page last updated: 2024-10-24

calmodulin-dependent protein phosphatase activity

Definition

Target type: molecularfunction

Catalysis of the reaction: protein serine/threonine phosphate + H2O = protein serine/threonine + phosphate, dependent on the presence of calcium-bound calmodulin. [GOC:mah, PMID:15359118]

Calmodulin-dependent protein phosphatase (CaM-PP) activity is a crucial regulatory mechanism in cellular signaling. These enzymes are members of the protein phosphatase family, which catalyze the removal of phosphate groups from protein substrates. The defining characteristic of CaM-PPs is their dependence on the calcium-binding protein calmodulin (CaM) for their activity.

CaM acts as a molecular switch, binding to CaM-PPs in response to increases in intracellular calcium concentrations. This binding event triggers a conformational change in the phosphatase, activating its catalytic activity. The activated enzyme can then dephosphorylate a wide range of protein substrates, modulating their activity and function.

CaM-PPs play diverse roles in cellular processes, including:

* **Signal transduction:** De-phosphorylation of target proteins involved in signal transduction pathways, such as kinases, phosphatases, and ion channels.
* **Muscle contraction:** Regulation of muscle contraction by de-phosphorylation of myosin light chain, a key component of the contractile apparatus.
* **Cellular growth and differentiation:** Control of cell growth and differentiation by de-phosphorylation of proteins involved in these processes.
* **Synaptic plasticity:** Modulation of synaptic plasticity in the nervous system by de-phosphorylating proteins involved in neuronal communication.

The molecular function of CaM-PPs involves a complex interplay between calcium, calmodulin, and protein substrates. By specifically removing phosphate groups from target proteins, CaM-PPs finely tune cellular responses to various stimuli, playing a critical role in maintaining cellular homeostasis and mediating diverse physiological functions.'
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Proteins (3)

ProteinDefinitionTaxonomy
Serine/threonine-protein phosphatase 2B catalytic subunit alpha isoformA protein phosphatase 3 catalytic subunit alpha that is encoded in the genome of human. [PRO:CNA, UniProtKB:Q08209]Homo sapiens (human)
Protein phosphatase 1AA protein phosphatase 1A that is encoded in the genome of human. [PRO:DNx, UniProtKB:P35813]Homo sapiens (human)
Serine/threonine-protein phosphatase 2B catalytic subunit beta isoformA serine/threonine-protein phosphatase 2B catalytic subunit beta isoform that is encoded in the genome of human. [PRO:DNx, UniProtKB:P16298]Homo sapiens (human)

Compounds (5)

CompoundDefinitionClassesRoles
cyanoginosin lrcyanoginosin LR: cyclic heptapeptide from cyanobacterium Microcystis aeruginosa

microcystin-LR : A microcystin consisting of D-alanyl, L-leucyl, (3S)-3-methyl-D-beta-aspartyl,L-arginyl, 2S,3S,4E,6E,8S,9S)-3-amino-4,5,6,7-tetradehydro-9-methoxy-2,6,8-trimethyl-10-phenyldecanoyl, D-gamma-glutamyl, and 2,3-didehydro-N-methylalanyl residues joined into a 25-membered macrocycle. Produced by the cyanobacterium Microcystis aeruginosa, it is the most studied of the microcystins.
microcystinbacterial metabolite;
EC 3.1.3.16 (phosphoprotein phosphatase) inhibitor;
environmental contaminant;
xenobiotic
tacrolimustacrolimus (anhydrous) : A macrolide lactam containing a 23-membered lactone ring, originally isolated from the fermentation broth of a Japanese soil sample that contained the bacteria Streptomyces tsukubaensis.

Tacrolimus: A macrolide isolated from the culture broth of a strain of Streptomyces tsukubaensis that has strong immunosuppressive activity in vivo and prevents the activation of T-lymphocytes in response to antigenic or mitogenic stimulation in vitro.
macrolide lactambacterial metabolite;
immunosuppressive agent
tamoxifenstilbenoid;
tertiary amino compound
angiogenesis inhibitor;
antineoplastic agent;
bone density conservation agent;
EC 1.2.3.1 (aldehyde oxidase) inhibitor;
EC 2.7.11.13 (protein kinase C) inhibitor;
estrogen antagonist;
estrogen receptor antagonist;
estrogen receptor modulator
cyclosporineramihyphin A: one of the metabolites produced by Fusarium sp. S-435; RN given refers to cpd with unknown MFhomodetic cyclic peptideanti-asthmatic drug;
anticoronaviral agent;
antifungal agent;
antirheumatic drug;
carcinogenic agent;
dermatologic drug;
EC 3.1.3.16 (phosphoprotein phosphatase) inhibitor;
geroprotector;
immunosuppressive agent;
metabolite
bi 201335faldaprevir: inhibits hepatitis C virus NS3 protease