Protein Transport Protein Sec24D

The regulation of intracellular vesicular trafficking is mediated by specific families of proteins that are involved in vesicular budding, translocation, and fusion of intracellular transport vesicles that selectively carry cargo proteins/lipids with target membranes.  Two major classes of vesicular carriers with in the endocytic and biosynthetic pathways are COPI/II and clatherin coated vesicles. Formation of coat protein complex II (COPII) vesicles requires the ordered assembly of the coat built from several cytosolic components GTPase Sar1, complexes of Sec23-Sec24 and Sec13-Sec31. The process is initiated by the conversion of GDP to GTP by the GTPase Sar1 which then recruits the heterodimeric complex of Sec23 and Sec24. This heterodimeric complex generates the pre-budding complex. The final step leading to membrane deformation and budding of COPII-coated vesicles is carried by the heterodimeric complex Sec13-Sec31. Sec23 and like proteins are very similar, both protein polypeptides fold in to 5 distinct domains, a beta-barrel a Zn finger, a vWA or trunk and all helical region and a C-terminal Gelsolin domain.  All Sec family members exhibit a partial MIDAS motif and the overall Para-Rossmann type fold which is characteristic of this superfamily. 

At least 4 different types of Sec24 proteins are characterized namely, Sec24A, Aec24B, Sec24C and Sec24D.  Sec24 of the COPII vesicle coat mediates the selective export of membrane proteins from the endoplasmic reticulum (ER) in yeast. Human cells express four Sec24 isoforms, but their role is unknown. Knockdown of single Sec24 isoforms showed dependence of di-leucine-mediated transport on Sec24A, but transport mediated by the other signals was not affected. By contrast, double knockdown of Sec24A with one of the other three Sec24 isoforms impaired all aromatic/hydrophobic signal-dependent transport (1).  By contrast, double knockdown of Sec24A with one of the other three Sec24 isoforms impaired all aromatic/hydrophobic signal-dependent transport. Double knockdown of Sec24B/C or Sec24B/D preferentially affected di-leucine-mediated transport, whereas knockdown of Sec24C/D affected di-isoleucine- and valine-mediated transport (1). Ebola virus envelop protein VP40 intracellular transport require Sec24C in ESCRTI complex that interacts with Nedd4 (2).  Mammalian Sec24 proteins exhibit close structural and functional homology to yeast Sec24 protein. 

Sec24C is a 1089 aa protein located on chromosome 5q31.1.  The Sec24A antibodies were generated using peptide corresponding to rat Sec24A protein. Sec24B-selective antibodies are affinity purified over immobilized antigen based affinity chromatography, and the purified immunoglobulins are stabilized in antibody stabilization buffer. FabGennix Int. Inc. will provide limited quantities of antigenic blocking peptide/protein for competition assays involving Sec24A antibodies. Antibodies to Sec24B (Sec24B-201AP) will label ~150kDa protein in Western blot positive control for Sec24A (PC-Sec24B) and several other cell lines.  FabGennix Inc. will conjugate this and other antibodies from its catalog to either secondary enzymes (alk-Pase or HRP) or fluorescent probes at a nominal cost upon request.  FabGennix also provides custom antibody production services for researchers that are looking for high affinity mono and polyclonal antibodies in various species. We specialize in making application specific antibodies that are useful in IHC, confocal and other applications where native antigen is detected. For a complete listing of all FabGennix antibodies please visit www.Fabgennix.com. 

Immunogen:          Synthetic peptide corresponding to unique epitope on Sec24D protein between aa 390-430.  The peptide sequence selected was post synthetically modified to achieve desired antigenicity before covalently coupling to a carrier protein.

Concentration:      Sec24D-401AP and FTITC-Sec24D:  IgG concentration 0.55-0.59 mg/ml in antibody stabilization buffer.

Applications:         Antibodies Sec24D-401AP is ideal for WB and immunoprecipitation, other applications have not been tested.  The species cross reactivity for these antibodies have not been examined fully.  WB: > 1:500; IMM & i.p pull-down assays: 1:200; IHC 1:200.  ELISA <1:10,000.  Application of this antibody in protocols not listed here does not necessarily exclude its use in such procedures. Investigators planning to use this antiobdy for applications not listed here can request a complimentary sample.

Reactivity:              This antibody detects a band of approximately ~150kDa in PC-Sec24D samples. There are some non-specific bands at 40-50kDa range, identity of these bands has not determined, but could represent proteolysis products.

Protocols:               Standard protocol for various applications (WB; IMM and IHC) of 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 isolated on immobilized antigen-affinity column and 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 0.45um filter after every use for long-term storage.

 

Notes:  Briefly centrifuge to collect liquid, heat or boil PC-Sec24D tube for 1-2 minutes to dissolve any precipitate before use.  This product is “ready-to-use” for electrophoresis. After thawing store at room temperature, Repeated freezing and thawing may result in appearance of higher MW immunoreactive bands.   

 

New Reagents:  Now you can recycle your western blots (nitrocellulose, supported membranes and PVFD membranes) by using our StripObuffer (Cat FGI-1989).  Each stripping is guaranteed to give better signal (up to 8 stripping).  No strong pungent smell of reducing agents or heating required.  Block in 5X diluObuffer and you are ready for blotting with a new antibody

 

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