Detection of Human HTRA2/Omi by Western Blot. Western blot shows lysates of SK‑Mel‑28 human malignant melanoma cell line, MCF‑7 human breast cancer cell line, HEK293 human embryonic kidney cell line, and HeLa human cervical epithelial carcinoma cell line. PVDF membrane was probed with 1 µg/mL of Mouse Anti-Human HTRA2/Omi Monoclonal Antibody (Catalog # MAB1458) followed by HRP-conjugated Anti-Mouse IgG Secondary Antibody (Catalog # HAF007). A specific band was detected for HTRA2/Omi at approximately 35 kDa (as indicated). This experiment was conducted under reducing conditions and using Immunoblot Buffer Group 4.
Preparation and Storage
Reconstitute at 0.5 mg/mL in sterile PBS.
The product is shipped at ambient temperature. Upon receipt, store it immediately at the temperature recommended below. *Small pack size (SP) is shipped with polar packs. Upon receipt, store it immediately at -20 to -70 °C
Stability & Storage
Use a manual defrost freezer and avoid repeated freeze-thaw cycles.
12 months from date of receipt, -20 to -70 °C as supplied.
1 month, 2 to 8 °C under sterile conditions after reconstitution.
6 months, -20 to -70 °C under sterile conditions after reconstitution.
HTRA2/Omi is the mammalian homologue of bacterial high temperature requirement protein (HtrA). HTRA2/Omi localizes to the mitochondria and is processed to expose an amino-terminal Reaper-like motif similar to SMAC/Diablo. HTRA2/Omi is released from the mitochondria in response to apoptotic insult and can interact with the BIR2 or BIR3 domains of XIAP to relieve caspase-IAP inhibition. This effect can be measured by reversing XIAP-BIR2 (R&D Systems, Catalog # 786-XB) inhibition of Caspase-7 (R&D Systems, Catalog # 823-C7) cleavage of a fluorogenic peptide (DEVD-AFC, MP Bio, Catalog # AFC-138). IC50 values for this effect are typically between 0.2 and 1.5 μM. HTRA2/Omi is trimeric and functions as a serine protease. The serine protease activity may play a more central role in apoptosis than its IAP antagonizing function. A PDZ domain regulates the serine protease activity by blocking access to the active site.
Suzuki, Y. et al. (2001) Mol. Cell. 8:613.
van Loo, G. et al. (2002) Cell Death & Diff. 9:20.
Hedge, R. et al. (2001) J. Biol. Chem. 277:432.
Verhagen, A. et al. (2001) J. Biol. Chem. 277:445.
Martins, L. et al. (2002) J. Biol. Chem. 277:439.
Silke, J., and A. Verhagen (2002) Cell Death & Diff. 9:362.
Savopoulos, J. et al. (2000) Protein Expression & Purification 19:227.
High Temperature Requirement Protein-2
Entrez Gene IDs:
27429 (Human); 64704 (Mouse)
High temperature requirement protein A2; HtrA serine peptidase 2; HTRA2; HtrA-like serine protease; Omi; OMIOmi stress-regulated endoprotease; PARK13EC 184.108.40.206; PRSS25; PRSS25serine, 25; Serine protease 25; serine protease HTRA2, mitochondrial; Serine proteinase OMI
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The data collected includes not only links to publications in PubMed,
but also provides information about sample types, species, and experimental conditions.
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