• Product name
  • Description
    Rabbit polyclonal to XAF1
  • Host species
  • Tested applications
    Suitable for: ICC/IF, WB, IHC-Pmore details
  • Species reactivity
    Reacts with: Mouse, Rat, Human
  • Immunogen

    Synthetic peptide (Human) (within the last 35 amino acids of C terminal end).

  • Positive control
    • Human spleen cell lysate.


  • Form
  • Storage instructions
    Shipped at 4°C. Store at +4°C.
  • Storage buffer
    Preservative: 0.02% Sodium Azide
    Constituents: PBS
  • Concentration information loading...
  • Purity
    Immunogen affinity purified
  • Clonality
  • Isotype
  • Research areas


Our Abpromise guarantee covers the use of ab17204 in the following tested applications.

The application notes include recommended starting dilutions; optimal dilutions/concentrations should be determined by the end user.

Application Abreviews Notes
ICC/IF Use at an assay dependent concentration. PubMed: 18485100
WB Use a concentration of 0.5 - 2 µg/ml. Detects a band of approximately 32 kDa.Can be blocked with Human XAF1 peptide (ab39906). A higher 50kDa band is present at times (lot dependent). This band is not blocked by the immunogen. We do not know the identity of this extra band.
IHC-P Use at an assay dependent concentration.


  • Function
    Seems to function as a negative regulator of members of the IAP (inhibitor of apoptosis protein) family. Inhibits anti-caspase activity of BIRC4. Induces cleavage and inactivation of BIRC4 independent of caspase activation. Mediates TNF-alpha-induced apoptosis and is involved in apoptosis in trophoblast cells. May inhibit BIRC4 indirectly by activating the mitochondrial apoptosis pathway. After translocation to mitochondra, promotes translocation of BAX to mitochondria and cytochrome c release from mitochondria. Seems to promote the redistribution of BIRC4 from the cytoplasm to the nucleus, probably independent of BIRC4 inactivation which seems to occur in the cytoplasm. The BIRC4-XAF1 complex mediates down-regulation of BIRC5/survivin; the process requires the E3 ligase activity of BIRC4. Seems to be involved in cellular sensitivity to the proapoptotic actions of TRAIL. May be a tumor suppressor by mediating apoptosis resistance of cancer cells.
  • Tissue specificity
    Widely expressed. Expression is frequently down-regulated in cancer cell lines. Isoform 5 is widely expressed. Expressed in placenta (at protein level).
  • Sequence similarities
    Contains 1 TRAF-type zinc finger.
  • Developmental stage
    Selectively expressed in third trimester placenta.
  • Cellular localization
    Nucleus and Cytoplasm. Nucleus. Mitochondrion. Found in the cytoplasm and nucleus of placental syncytiotrophoblasts. Translocates to mitochondria upon TNF-alpha treatment.
  • Information by UniProt
  • Database links
  • Alternative names
    • BIRC 4 binding protein antibody
    • BIRC4 binding protein antibody
    • BIRC4-binding protein antibody
    • BIRC4BP antibody
    • HSXIAPAF 1 antibody
    • HSXIAPAF1 antibody
    • XAF 1 antibody
    • XAF1 antibody
    • XAF1_HUMAN antibody
    • XIAP associated factor 1 antibody
    • XIAP-associated factor 1 antibody
    • XIAPAF1 antibody
    see all


  • Lane 1 : Anti-XAF1 antibody (ab17204) at 0.5 µg/ml
    Lane 2 : Anti-XAF1 antibody (ab17204) at 1 µg/ml
    Lane 3 : Anti-XAF1 antibody (ab17204) at 2 µg/ml

    Lane 1 : Human spleen lysate
    Lanes 2-3 : Human spleen lysate

    Observed band size: 32 kDa (why is the actual band size different from the predicted?)

    Western blot analysis of XAF1 in human spleen lysate with ab17204 at

    Lane A: 0.5 ug/ml

    Lane B: 1ug/ml 

    Lane C: 2ug/ml 

    Higher 50kDa band presence is lot dependent. This band is not blocked by the immunogen.
  • ab17204 at 2µg/ml staining XAF1 in human spleen tissue by IHC

  • ICC/IF image of ab17204 stained HeLa cells. The cells were 4% formaldehyde fixed (10 min) and then incubated in 1%BSA / 10% normal goat serum / 0.3M glycine in 0.1% PBS-Tween for 1h to permeabilise the cells and block non-specific protein-protein interactions. The cells were then incubated with the antibody (ab17204, 5µg/ml) overnight at +4°C. The secondary antibody (green) was Alexa Fluor® 488 goat anti-rabbit IgG (H+L) used at a 1/1000 dilution for 1h. Alexa Fluor® 594 WGA was used to label plasma membranes (red) at a 1/200 dilution for 1h. DAPI was used to stain the cell nuclei (blue) at a concentration of 1.43µM.


This product has been referenced in:
  • Ou Z  et al. Olig2-Targeted G-Protein-Coupled Receptor Gpr17 Regulates Oligodendrocyte Survival in Response to Lysolecithin-Induced Demyelination. J Neurosci 36:10560-10573 (2016). WB ; Rat . Read more (PubMed: 27733608) »
  • Chen ZX  et al. RNA helicase A is a downstream mediator of KIF1Bß tumor-suppressor function in neuroblastoma. Cancer Discov 4:434-51 (2014). Read more (PubMed: 24469107) »

See all 6 Publications for this product

Customer reviews and Q&As

Immunocytochemistry/ Immunofluorescence
Human Cell (HEK293)
Yes - 0.3% Triton X-100 in blocking buffer
Blocking step
Serum as blocking agent for 1 hour(s) and 0 minute(s) · Concentration: 5% · Temperature: 25°C

Abcam user community

Verified customer

Submitted Feb 13 2018

Western blot
Loading amount
25 µg
Gel Running Conditions
Reduced Denaturing
Human Tissue lysate - whole (liver)
Blocking step
Milk as blocking agent for 1 hour(s) and 0 minute(s) · Concentration: 5% · Temperature: 23°C

Abcam user community

Verified customer

Submitted Dec 24 2014

Western blot
Loading amount
25 µg
Gel Running Conditions
Reduced Denaturing
Mouse Cell lysate - whole cell (hepatocytes)
Blocking step
Milk as blocking agent for 1 hour(s) and 0 minute(s) · Concentration: 5% · Temperature: 23°C

Abcam user community

Verified customer

Submitted Dec 22 2014

Thank you for your enquiry. I can confirm the following antigen retrieval methods were used in testing of these antibodies. Please not that this may require individual optimization by customers in their own experiments: ab17204 XAF1 antibody ...

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Thank you for calling Abcam earlier. Please let me know how you would like to proceed in regards to testing a second XAF1 antibody, potentially ab98913, which is the antibody we talked about on the telephone. I look forward to your reply

Thank you for your email. Since the antibody was raised against the C-terminal region of the full length protein, the antibody can bind to the following isoforms: isoform 1 (35 kDa) isoform 2 (32 kDa) isoform 6 (22.5 kDa) isoform 7 (34.5 kDa) ...

Read More

Thank you for your enquiry. According to the following publication XIAP is localised to the nucleus in HeLa cells transfected with an RFP tagged version of the protein. Identification of XAF1 as an antagonist of XIAP anti-Caspase activity. 2001 ...

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Abcam guarantees this product to work in the species/application used in this Abreview.
Western blot
Rat Cell lysate - other (primary cortical neurons)
Loading amount
25 µg
primary cortical neurons
Blocking step
Other as blocking agent for 1 hour(s) and 0 minute(s) · Concentration: 1x

Abcam user community

Verified customer

Submitted May 09 2006


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