Carbonic Anhydrase 2 Protein, Mouse, Recombinant (His) is expressed in E. coli expression system with His tag. The predicted molecular weight is 30.4 kDa and the accession number is AAH55291.1.

Essential for bone resorption and osteoclast differentiation. Reversible hydration of carbon dioxide. Contributes to intracellular pH regulation in the duodenal upper villous epithelium during proton-coupled peptide absorption. Stimulates the chloride-bicarbonate exchange activity of SLC26A6. Carbonic Anhydrase 2 Protein, Rat, Recombinant (His) is expressed in E. coli expression system with N-6xHis tag. The predicted molecular weight is 31.7 kDa and the accession number is P27139.

S100A8 and S100A9 (also known as MRP8 and MRP14, respectively) are Ca2 binding proteins belonging to the S100 family. They often exist in the form of heterodimer, while homodimer exists very little because of the stability. S100A8/A9 is constitutively expressed in neutrophils and monocytes as a Ca2 sensor, participating in cytoskeleton rearrangement and arachidonic acid metabolism. S100A9 Protein, Cynomolgus, Recombinant (His) is expressed in E. coli expression system with N-His tag. The predicted molecular weight is 14.70 kDa and the accession number is A0A2K5VRV3.

Cornulin is a member of the fused gene family of molecular chaperones. Human Cornulin contains N-terminus EF-hand domains and Ca2+ binding domains, and two glutamine- and threonine-rich 60 amino acid repeats in its C-terminus. Cornulin involves in the mucosal/epithelial immune response and epidermal differentiation. Cornulin is a survival factor that participates in the clonogenicity of squamous esophageal epithelium cell lines, attenuates deoxycholic acid (DCA)-induced apoptotic cell death and release of calcium. When Cornulin is overexpressed in oral squamous carcinoma cell lines, it regulates negatively cell proliferation by the induction of G1 arrest.

Annexin A6, also known as ANXA6 or ANXAⅥ, belongs to a family of Ca2+-dependent membrane and phospholipid binding proteins. Members of this family have been implicated in membrane-related events along exocytotic and endocytotic pathways. Annexin 6 is phosphorylated in vivo associated with cell growth. Annexin 6 was not phosphorylated in quiescent cells, but was phosphorylated on serine and to a lesser extent threonine, several hours following cell stimulation. Experiment has revealed the presence of annexin A6 on the cell surface of variety cells as putative receptors and / or binding proteins for chondroitin sulfate proteoglycans, helping cells to bind with this extracellular matrix glycosaminoglycan chondroitin sulfate which is related to the cell-substratum adhesion. A post-tranlational modification other than direct protein phosphorylation may influence the activity of annexin6 and provide evidence linking cell growth with regulation of annexin 6 function.

Stromal interaction molecule 1, also known as STIM1 and GOK, is a cell membrane, a single-pass type I membrane protein and a endoplasmic reticulum membrane protein. STIM1 / GOK is ubiquitously expressed in various human primary cells and tumor cell lines. It contains one EF-hand domain and one SAM (sterile alpha motif) domain. STIM1 / GOK plays a role in mediating Ca2+influx following depletion of intracellular Ca2+stores. It acts as Ca2+sensor in the endoplasmic reticulum via its EF-hand domain. Upon Ca2+depletion, STIM1 / GOK translocates from the endoplasmic reticulum to the plasma membrane where it activates the Ca2+release-activated Ca2+(CRAC) channel subunit, TMEM142A / ORAI1. Transfection of STIM1 / GOK into cells derived from a rhabdoid tumor and from a rhabdomyosarcoma that do not express detectable levels of STIM1 can induce cell death, suggesting a possible role in the control of rhabdomyosarcomas and rhabdoid tumors. Defects in STIM1 are the cause of immune dysfunction with T-cell inactivation due to calcium entry defect type 2 (IDTICED2) which is an immune disorder characterized by recurrent infections, impaired T-cell activation and proliferative response, decreased T-cell production of cytokines, lymphadenopathy, and normal lymphocytes counts and serum immunoglobulin levels.

Has bactericidal activity. May act as a ligand for C-C chemokine receptor CCR6. Positively regulates the sperm motility and bactericidal activity in a CCR6-dependent manner. Binds to CCR6 and triggers Ca2+ mobilization in the sperm which is important for its motility. DEFB1 Protein, Pig, Recombinant (GST) is expressed in E. coli expression system with N-GST tag. The predicted molecular weight is 31.1 kDa and the accession number is O62697.

Has bactericidal activity. May act as a ligand for C-C chemokine receptor CCR6. Positively regulates the sperm motility and bactericidal activity in a CCR6-dependent manner. Binds to CCR6 and triggers Ca2+ mobilization in the sperm which is important for its motility.

LSP1 (Lymphocyte Specific Protein 1) is a Protein Coding gene. This gene encodes an intracellular F-actin binding protein. The protein is expressed in lymphocytes, neutrophils, macrophages, and endothelium and may regulate neutrophil motility, adhesion to fibrinogen matrix proteins, and transendothelial migration. LSP1 is a lymphocyte-specific intracellular Ca2(+)-binding protein. LSP1 localizes to nascent phagocytic cups during Fcgamma receptor-mediated phagocytosis, where it displays the same spatial and temporal distribution as the actin cytoskeleton. Down-regulation of LSP1 severely reduces the phagocytic activity of macrophages, clearly demonstrating a crucial role for this protein in Fcgamma receptor-mediated phagocytosis. LSP1, expressed in endothelial cells, plays a pivotal role in regulating subsequent recruitment steps following leukocyte adhesion.

Coagulation factor X, also known as FX, F10, Eponym Stuart-Prower factor, and thrombokinase, is an enzyme of the coagulation cascade. It is one of the vitamin K-dependent serine proteases, and plays a crucial role in the coagulation cascade and blood clotting, as the first enzyme in the common pathway of thrombus formation. Factor X deficiency is one of the rarest of the inherited coagulation disorders. FX deficiency among the most severe of the rare coagulation defects, typically including hemarthroses, hematomas, and umbilical cord, gastrointestinal, and central nervous system bleeding. Factor X is synthesized in the liver as a mature heterodimer formed from a single-chain precursor, and vitamin K is essential for its synthesis. Factor X is activated into factor Xa (FXa) by both factor IX (with its cofactor, factor VIII in a complex known as intrinsic Xase) and factor VII (with its cofactor, tissue factor in a complex known as extrinsic Xase) through cleaving the activation propeptide. As the first member of the final common pathway or thrombin pathway, FXa converts prothrombin to thrombin in the presence of factor Va, Ca2+, and phospholipid during blood clotting and cleaves prothrombin in two places (an arg-thr and then an arg-ile bond). This process is optimized when factor Xa is complexed with activated cofactor V in the prothrombinase complex. Inborn deficiency of factor X is very uncommon, and may present with epistaxis (nose bleeds), hemarthrosis (bleeding into joints) and gastrointestinal blood loss. Apart from congenital deficiency, low factor X levels may occur occasionally in a number of disease states. Furthermore, factor X deficiency may be seen in amyloidosis, where factor X is adsorbed to the amyloid fibrils in the vasculature.

B-cell linker protein, also known as B-cell adapter containing a SH2 domain protein, B-cell adapter containing a Src homology 2 domain protein, Cytoplasmic adapter protein, Src homology 2 domain-containing leukocyte protein of 65 kDa, SLP-65 and BLNK, is a cytoplasm and cell membrane protein which contains oneSH2 domain. BLNK is expressed in B-cell lineage and fibroblast cell lines. Highest levels of expression is in the spleen, with lower levels in the liver, kidney, pancreas, small intestines and colon. BLNK functions as a central linker protein that bridges kinases associated with the B-cell receptor (BCR) with a multitude of signaling pathways, regulating biological outcomes of B-cell function and development. BLNK plays a role in the activation of ERK / EPHB2, MAP kinase p38 and JNK. BLNK modulates AP1 activation. It is important for the activation of NF-kappa-B and NFAT. BLNK plays an important role in BCR-mediated PLCG1 and PLCG2 activation and Ca2+mobilization and is required for trafficking of the BCR to late endosomes. BLNK may be required for the RAC1-JNK pathway. It plays a critical role in orchestrating the pro-B cell to pre-B cell transition. BLNK also plays an important role in BCR-induced B-cell apoptosis.Defects in BLNK are the cause of agammaglobulinemia type 4 (AGM4) which is a primary immunodeficiency characterized by profoundly low or absent serum antibodies and low or absent circulating B cells due to an early block of B-cell development.

Transglutaminases (TGase) are a family of calcium-dependent acyl-transfer enzymes ubiquitously expressed in mammalian cells and responsible for catalyzing covalent cross-links between proteins or peptides. Transglutaminase 3 (TGM3) is a member of a family of Ca2+-dependent enzymes that catalyze covalent cross-linking reactions between proteins or peptides. TGM3 isoform is widely expressed and is important for epithelial barrier formation. It is a zymogen, requiring proteolysis for activity. Calcium-activated TGM3 can bind, hydrolyze, and is inhibited by GTP, despite lacking structural homology with other GTP binding proteins. TGM3 displays a diffuse cytoplasmic distribution in vitro consistent with its proposed role in the early phase of cornified cell envelope assembly in the cytoplasm. TGM3-driven specific isopeptide bonds between intermediate filaments and KAPs participate to the progressive scaffolding of the hair shaft. Additionally, TGM3 may be a novel prognostic biomarker for esophageal squamous cell carcinoma (ESCC).

The Fc receptor with low affinity for IgG (FCGR3, or CD16) is encoded by 2 nearly identical genes, FCGR3A and FCGR3B, resulting in tissue-specific expression of alternative membrane-anchored isoforms. FCGR3A, it is also known as CD16a, encodes a transmembrane protein expressed on activated monocytes/macrophages, natural killer (NK) cells, and a subset of T cells. CD16a / FCGR3A is a receptor expressed on NK cells that facilitates antibody dependent cellular cytotoxicity (ADCC) by binding to the Fc portion of various antibodies. CD16a / FCGR3A also has a broader function. CD16a / FCGR3A is directly involved in the lysis of some virus-infected cells and tumor cells by NK cells, independent of antibody binding. Cross-linking of CD16a / FCGR3A on NK cells resulted in increased intracellular Ca2+ levels and a cascade of biochemical events similar to those activated by the T cell receptor. CD16a / FCGR3A on human NK cells is a lysis receptor that mediates the direct killing of some virus infected and tumor cells, independent of antibody ligation.

Vascular endothelial growth factor-B (VEGF-B) is closely related to VEGF-A, an effector of blood vessel growth during development and disease and a strong candidate for angiogenic therapies. In detail, VEGFB can positively prevent the Ang II-induced rising in the size of cardiomyocyte as well as reduce Ang II-induced mRNA and protein levels of β-MHC (β-myosin heavy chain), BNP (brain natriuretic peptide), and ANP (atrial natriuretic peptide). Moreover, VEGFB can regulate the decline of the Ang II-induced rising in Ca2+.

CD39L1 protein (ENTPD2 or NTPDase2) is a member of the ecto-nucleoside triphosphate diphosphohydrolase family which the main role is termination of purinergic signaling. CD39L1 gene encodes a precursor protein with 495 amino acid residues which generates a 437 amino acid residues mature protein after processing. It is an ecto-nucleotidase that found on the surface of vascular adventitial cells and accessory vascular cells. CD39L1 is a Ca2+- and Mg2+-dependent enzyme that activates platelets by preferentially converting ATP to ADP. CD39L1 plays a role in regulating thrombosis and inflammation which is considered to be a therapeutic target for thromboregulation and the treatment of vascular inflammation. Alternative splicing of CD39L1 gene results in multiple transcript variants.

Neurocalcin-delta (NCALD) is a neuronal calcium-binding protein that belongs to the neuronal calcium sensor (NCS) family. It expressed in mammalian brains. NCALD contains an N-terminal myristoylation signal and four EF-hand calcium binding loops. The protein possesses a Ca2+ /myristoyl switch. It is cytosolic at resting calcium levels. However, elevated intracellular calcium levels induce a conformational change which exposes the myristoyl group, resulting in protein association with membranes and partial co-localization with the perinuclear trans-golgi network. NCALD protein is thought to be a regulator of G protein-coupled receptor signal transduction.

P-selectin/CD62P is a single-pass type I membrane protein which is a member of the Selectin family. It consists 768 amino acid (aa). P-selectin is a cell surface glycoprotein expressed by activated platelets and endothelial cells. It induced expression in lung, liver, kidney and heart after endotoxin treatment. Ca2+-dependent receptor for myeloid cells that binds to carbohydrates on neutrophils and monocytes. It mediates the interaction of activated endothelial cells or platelets with leukocytes. The ligand recognized is sialyl-Lewis X. it also mediates rapid rolling of leukocyte rolling over vascular surfaces during the initial steps in inflammation through interaction with PSGL1. P-selectin interacts with SNX17, PSGL1/SEPL, PODXL2, mediates neutrophil adhesion and leukocyte rolling. This interaction requires the sialyl-Lewis X epitope of PSGL1 and PODXL2, and specific tyrosine sulfation on PSGL1.

Protein Phosphatase 1 Regulatory Subunit 14A (PPP1R14A) belongs to the PP1 inhibitor family. PPP1R14A is mapped to chromosome 19q13.13-q13.2. PPP1R14A binds directly to protein kinase C and casein kinase I. Meantime, PPP1R14A is a phosphorylation-dependent inhibitor of smooth muscle myosin phosphatase. PPP1R14A is the inhibitor of PPP1CA. When phosphorylated, PPP1R14A has over 1000-fold higher inhibitory activity, creating a molecular switch for regulating the phosphorylation status of PPP1CA substrates and smooth muscle contraction. In addition, inhibition of PPP1R14A also enhances contraction of smooth muscle in the absence of increment of intracellular Ca2+ concentration.

Calmodulin-like protein 3 (CALML3) is similar to that of authentic calmodulin and may actually compete with calmodulin by binding, with different affinity, to cellular substrates. Calmodulin-like protein 3 (CALML3) is a tumor-sensitive protein specifically expressed in normal epithelial cells but downregulated in tumorigenesis. Downregulation of the protein is an early event in breast cancer development. One of the most pressing questions raised by the discovery of CLP/CALML3 is that of its potential targets. Although it is 85% identical to human calmodulin, the distinct properties of CLP suggest that it has specific targets or targets that only partially overlap with those of calmodulin. Research has identified the unconventional myosin-10 (Myo10) as a specific target of CALML3. The discovery of Myo10 as a specific target of CALML3 is highly significant and suggests multiple lines of further research such as investigations of the Ca2+ regulation of Myo10 and the role of the loss of CLP in epithelial differentiation, adhesion, and cancer. Cells expressing CALML3 displayed a striking increase in the number and length of myosin-10-positive filopodia and showed increased mobility in a wound healing assay.

Synaptosomal-associated protein 25, also known as Super protein, Synaptosomal-associated 25 kDa protein, SNAP25 and SNAP, is a cytoplasm and cell membrane protein that belongs to the SNAP-25 family. SNAP25 / SUP contains 2 t-SNARE coiled-coil homology domains. SNAP25 / SUP is a membrane bound protein anchored to the cytosolic face of membranes via palmitoyl side chains in the middle of the molecule. SNAP25 / SUP protein is a component of the SNARE complex, which is proposed to account for the specificity of membrane fusion and to directly execute fusion by forming a tight complex that brings the synaptic vesicle and plasma membranes together. SNAP25 / SUP is a Q-SNARE protein contributing two α-helices in the formation of the exocytotic fusion complex in neurons where it assembles with syntaxin-1 and synaptobrevin. SNAP25 / SUP is involved in the molecular regulation of neurotransmitter release. It may play an important role in the synaptic function of specific neuronal systems. SNAP25 / SUP associates with proteins involved in vesicle docking and membrane fusion. SNAP25 / SUP regulates plasma membrane recycling through its interaction with CENPF. SNAP25 / SUP inhibits P/Q- and L-type voltage-gated calcium channels located presynaptically and interacts with the synaptotagmin C2B domain in Ca2+-independent fashion. In glutamatergic synapses SNAP25 / SUP decreases the Ca2+ responsiveness, while it is naturally absent in GABAergic synapses.

Pancreatic derived factor, also known as FAM3B, is an islet-specific secreted cytokine specifically expressed at high levels in the islets of Langerhans of the endocrine pancreas. FAM3B protein is present in alpha- and beta- cells of pancreatic islets, insulin-secreting beta-TC3 cells, and glucagon-secreting alpha-TC cells. FAM3B causes apoptosis of beta-cells as assessed by electron microscopy, annexin Ⅴ fluorescent staining, and flow-cytometric terminal deoxynucleotidyl transferase-mediated dUTP nick-end labeling assay. FAM3B activated caspase-3 while not affect cytosolic Ca2+levels or nitric oxide levels. Hense, FAM3B may have a role in the process of pancreatic?-cell apoptosis of primary islet and cell lines. FAM3B secretion is regulated by glucose and other insulin secretagogues. This islet-specific secreted cytokine is secreted from both pancreatic alpha- and beta- cells. Glucose stimulates FAM3B secretion dose dependently in beta- cell lines and primary islets but not in alpha-cells. It is likely cosecreted with insulin via the same regulatory mechanisms and structure and conformation is vital for FAM3B secretion.

Calmodulin-Dependent Protein Kinase (CaM Kinase) is a kind of protein phosphorylate multiple downstream targets. Concentration of cytosolic calcium functions as a second messenger that mediates a wide range of cellular responses. Calcium binds to calcium binding proteins (calmodulin/CaM) and stimulates the activity of a variety of enzymes, including CaM kinases referred to as CaM-kinases (CaMKs), such as CaMKI, CaMKII, CaMKIV and CaMKK. Calmodulin-dependent protein kinase CL3/CaMKIγ is a memberane-anchored CaMK belonging to the CaM kinase family. Its C-terminal region is uniquely modified by two sequential lipidification steps: prenylation followed by a kinase-activity-regulated palmitoylation. These modifications are essential for CaMKIγ membrane anchoring and targeting into detergent-resistant lipid microdomains in the dendrites. It has been found that CaMKIγ critically contributed to BDNF-stimulated dendritic growth. Raft insertion of CaMKIγ specifically promoted dendritogenesis of cortical neurons by acting upstream of RacGEF STEF and Rac, both present in lipid rafts. Thus, CaMKIγ may represent a key element in the Ca2+-dependent and lipid-raft-delineated switch that turns on extrinsic activity-regulated dendrite formation in developing cortical neurons.

S100A8 and S100A9 (also known as MRP8 and MRP14, respectively) are Ca2 binding proteins belonging to the S100 family. They often exist in the form of heterodimer, while homodimer exists very little because of the stability. S100A8/A9 is constitutively expressed in neutrophils and monocytes as a Ca2 sensor, participating in cytoskeleton rearrangement and arachidonic acid metabolism. S100A9 Protein, Canine, Recombinant (His) is expressed in E. coli expression system with N-His tag. The predicted molecular weight is 15.90 kDa and the accession number is XP_038528057.1.

Ca2+-regulated heat-stable protein of 24 kDa (CRHSP-24) is a serine phosphoprotein originally identified as a physiological substrate for the Ca2+-calmodulin regulated protein phosphatase calcineurin (PP2B). CRHSP-24 is a paralog of the brain-specific mRNA-binding protein PIPPin and was recently shown to interact with the STYX/dead phosphatase protein in developing spermatids.

Serine/Threonine-Protein Phosphatase PP1-Υ Catalytic Subunit (PPP1CC) is a member of the PPP phosphatase family. It is essential for cell division, participates in the regulation of glycogen metabolism, muscle contractility and protein synthesis. PPP1CC colocalizes with SPZ1 in the nucleus, with URI1 at mitochondrion, Rapidly exchanges between the nucleolar, nucleoplasmic and cytoplasmic compartments. As a cofactor, PPP1CC binds one iron ion and one manganese ion per subunit.. In addition, PPP1CC may play an important role in dephosphorylating substrates such as the postsynaptic density-associated Ca2+/calmodulin dependent protein kinase II.

Reticulocalbin-2 (RCN2, also named as ERC-55), is a 55-kDa Ca2+-binding protein containing six EF-hands, which was identified to be localized in endoplasmic reticulum. RCN2 is belonging to Reticulocalbin (RCN) family, the family members could play oncogenic roles in human malignancies and facilitate tumor cell proliferation and metastasis. Recently, studies on RCN2 functions mainly focused on its role in differentiation and endocrine regulation in mouse. Another study has suggested that RCN2 could be a potential tumor-associated antigen for mammary cancer immunological prevention. Up to now, the experimental evidence uncovering the role of RCN2 in cancer is very limited.

Ca2+/calmodulin-dependent protein kinase2A (CAMK2A) belongs to the serine/threonine protein kinase family and, together with other 28 different isoforms, belongs to the Ca2+/ calmodulin-dependent protein kinase subfamily. CaM kinase Ⅱ is thought to be an important mediator of learning and memory and is also necessary for Ca2+homeostasis and reuptake in cardiomyocytes chloride transport in epithelia, positive T-cell selection, and CD8 T-cell activation. CAMKIIA is one of the major forms of CAMKII. It has been found to play a critical role in sustaining activation of CAMKII at the postsynaptic density. Studies have found that knockout mice without CAMKIIA demonstrate a low frequency of LTP. Additionally, these mice do not form persistent, stable place cells in the hippocampus.

Plays an important role in the regulation of different protein degradation mechanisms and pathways including ubiquitin-proteasome system (UPS), autophagy and endoplasmic reticulum-associated protein degradation (ERAD) pathway. Mediates the proteasomal targeting of misfolded or accumulated proteins for degradation by binding (via UBA domain) to their polyubiquitin chains and by interacting (via ubiquitin-like domain) with the subunits of the proteasome. Plays a role in the ERAD pathway via its interaction with ER-localized proteins UBXN4, VCP and HERPUD1 and may form a link between the polyubiquitinated ERAD substrates and the proteasome. Isoform 1, isoform 2 and isoform 3 play a role in unfolded protein response (UPR) by attenuating the induction of UPR-inducible genes, DDTI3/CHOP, HSPA5 and PDIA2 during ER stress. Involved in the regulation of macroautophagy and autophagosome formation; required for maturation of autophagy-related protein LC3 from the cytosolic form LC3-I to the membrane-bound form LC3-II and may assist in the maturation of autophagosomes to autolysosomes by mediating autophagosome-lysosome fusion. Negatively regulates the TICAM1/TRIF-dependent toll-like receptor signaling pathway by decreasing the abundance of TICAM1 via the autophagic pathway. Isoform 1 and isoform 3 play a key role in the regulation of the levels of PSEN1 by targeting its accumulation to aggresomes which may then be removed from cells by autophagocytosis. Promotes the ubiquitination and lysosomal degradation of ORAI1, consequently downregulating the ORAI1-mediated Ca2+ mobilization. Suppresses the maturation and proteasomal degradation of amyloid beta A4 protein (A4) by stimulating the lysine 63 (K63)-linked polyubiquitination. Delays the maturation of A4 by sequestering it in the Golgi apparatus and preventing its transport to the cell surface for subsequent processing.

Calmodulin (CaM) is a multifunctional intermediate calcium-binding messenger protein expressed in all eukaryotic cells. It is an intracellular target of the secondary messenger Ca2+, and the binding of Ca2+ is required for the activation of Calmodulin. Once bound to Ca2+, Calmodulin acts as part of a calcium signal transduction pathway by modifying its interactions with various target proteins such as kinases or phosphatases. Calmodulin is a small, highly conserved protein that is 148 amino acids long. The protein has two approximately symmetrical globular domains each containing a pair of EF-hand motifs (the N- and C-domain) separated by a flexible linker region for a total of four Ca2+ binding sites. Calmodulin mediates many crucial processes such as inflammation, metabolism, apoptosis, smooth muscle contraction, intracellular movement, short-term and long-term memory, and the immune response. Calmodulin is expressed in many cell types and can have different subcellular locations, including the cytoplasm, within organelles, or associated with the plasma or organelle membranes, but it is always found intracellularly.

Human Sulfatase Modifying Factor 1 (SUMF1) is a 42kDa protein. SUMF1 is a Ca2+-binging member of the sulfatase-modifying factor family. SUMF1 is a soluble ER lumenal glycoprotein, it converts inactive sulfatases into an active form by transforming a catalytic site cysteine into a formylglycine residue. In the ER, SUMF1 can exist as either a monomer, or a disulfide-linked homodimer or a heterodimer with SUMF2. Three splice isoforms are known.

CD19 is a 95 kDa transmembrane glycoprotein that plays a central role in B cell activation and humoral immune responses.Functions as coreceptor for the B-cell antigen receptor complex (BCR) on B-lymphocytes. Decreases the threshold for activation of downstream signaling pathways and for triggering B-cell responses to antigens. Activates signaling pathways that lead to the activation of phosphatidylinositol 3-kinase and the mobilization of intracellular Ca2 stores.

CAPG, also known as actin Regulatory Protein CAPG, is a a member of the gelsolin/villin family. Members of this family are actin-regulatory proteins. CAPG reversibly blocks the barbed ends of F-actin filaments in a Ca2+ and phosphoinositide-regulated manner, but does not sever preformed actin filaments. By capping the barbed ends of actin filaments, CAPG contributes to the control of actin-based motility in non-muscle cells. CAPG may also play an important role in macrophage function.