Double C2 domain like protein B

Accession # AAB47747; Other Nomenclature:Double C2-like domain-containing protein beta-like

Two synaptic vesicle associated proteins, Rabphilin and Doc2 are believed to be Ca+2 sensors in neurotransmitter release.  A homolog of Doc2 proteins that is ubiquitously present in all tissue and function as calcium sensor in all other tissues called Doc2beta (Doc2b).  Doc2b is present on all tissues, the encoded protein had 412 amino acids and is highly homologues to its other isoform, Doc2alpha with 70% identity. The identity of Doc2b with Doc2 protein in specially high in two C2 domains.  C2A and C2B. the Doc2b protein binds to posphotidylcholine (PC) and phosphotidylserine (PS) at C2A domain at EC50 of 1uM (1). Doc2A and Doc2b genes are implicated in synaptic vesicle exocytosis in different neurons.  Doc2b is also interacts with Dynein-dependent intracellular vesicle transport via interaction with cathepsin D and mannose 6 phosphate receptor interaction (2).  

Doc2b is highly expressed as early as embryonic dat 12 (E12) throughout the neuroepithelium, long before the neurotransmission is functional. In contrast the Doc2A transcripts are first detected at E17 in ventral brain areas (3). Doc2b is a peripheral protein with a short unique N-terminus and two C2 domains. Doc2b is regulating the Ca-depndent exocytosis by translocating itself to plasma membrane die to a small rise in intracellular Ca increase leading to efficient expansion of fusion pore, leading to increased release of catecholamines (4). Interactions of doc2b with syntaxin 4 in response to insulin release cause a Ca-dependent fusion of Glut 4 vesicle with the plasma membrane allowing an increase density of Glut 4 on cell surface (5).  Doc2b acts as a priming factor and increases the number of fusion-competent vesicles on the plasma membrane.  Doc2b is a 45 kDa protein expressed ubiquitously. It resembles synaptotagmin 1 but lacks trnansmembrane domain and its C2 doamin has relatively high affinity for Ca. 

The doc2b-selective antibodies were generated against unique antigenic sequence near C-terminal end (from amino acids 360-412). The antibodies to Doc2b are affinity purified over immobilized antigen based chromatography, and the purified immunoglobulins are stabilized in antibody stabilization buffer. The affinity purified antibodies are also conjugated to FITC and biotin for direct applications in IHC and cell sorting experiments.  FabGennix Int. Inc.,  also provide limited quantities of antigenic blocking peptides for Doc2b-201AP.  Antibodies to Doc2b (Doc2b-201AP) will label both Doc2b protein but will not label Doc2a subtype variants.  Limited quantities of Western blot positive control for Doc2b (PC-Doc2b) is also available in ready-to-use buffer for SDS-PAGE and western blotting experiments.   

Immunogen:            Synthetic peptide taken form the Doc2b gene form within the C-terminal region (amino acid 360-412), the peptide was post-synthetically modified and conjugated to carrier protein to achieve desired antigenicity.  The Doc2b peptide sequence was conserved in rat, mouse and human protein and also present in other species.   

Concentration:         Doc2b-201AP and Doc2b-FITC:  IgG concentration 0.58-061mg/ml in antibody stabilization buffer.

Applications:           Antibody Doc2b-201AP is ideal for WB and ELISA applications, other applications have not been tested.  This antibody does not cross react to other calcium binding proteins.  The species cross reactivity for this antibody is not examined fully.  The dilutions for this antibody is for reference only, investigators are expected to determine the optimal conditions for specific assay.  WB: > 1:500; IMM & i.p pull-down assays: n.d; IHC n.d.  ELISA <1:10,000 

Reactivity:               This antibody detects a single band of approximately 45kDa in PC-Doc2b samples. When indicated n.d for specific application of this antibody means the antibody has not been tried for that application and it does not mean not suitable for that application. Investigators using this antiobdy in applications not listed here can ask for a free complimentary sample of this antibody.

Protocols:                Standard protocol for various applications (WB; IMM and IHC) of this antibody can be requested by calling Technical support line, basic information on this antibody is provided with the product specification sheet, however, FabGennix Inc.  strongly recommends investigators to optimize conditions for use of this antibody in their laboratories.  

Form/Storage:         The affinity-purified antibodies are supplied as stabilized product.  Store at -20^oC for long-term storage.  FabGennix Inc. does not recommend storage of very dilute antibody solutions unless they are prepared in specially formulated multi use antibody dilution buffer (Cat # DiluOBuffer).  Working solutions of antibodies in DiluOBuffer should be filtered through 0.45u filter after every use for long-term storage.

 

   

For research use only, not for diagnostic or therapeutic use.