Survivin is a member of the family of inhibitor of apoptosis proteins (IAP), and is involved in both the control of apoptosis and regulation of cell division. IAPs suppress mitochondria-dependent and -independent apoptosis by binding to and inhibiting caspases through their BIR domains (reviewed in Liston et al, 2003; Wright and Duckett, 2005). Resistance towards apoptosis is a hallmark of cancer cells, and overexpression of IAPs can contribute to the development of cancer though inhibiting apoptosis. In addition to at least one BIR domain, some IAP members also have a RING-type finger motif at their carboxyl-terminal. Structurally, survivin is composed of a single BIR domain and an extended COOH-terminal a-helical coiled-coil domain; survivin does not contain a RING-finger domain. Survivin is highly expressed in embryonic and fetal organs, and is cell cycle regulated with a marked increase in the G2M phase where it plays a role in facilitating cell division (reviewed in Li, 2005 and Zaffaroni et al, 2005). Survivin is undetectable in most normal differentiated and non-proliferating tissues, but is highly expressed in cancer. Expression has been described in the majority of human tumor types including lung, breast, colon, gastric, leukemias, neuroblastoma, brain tumors, pheochromocytoma, soft tissue sarcomas, melanomas and other skin tumors. Additionally, survivin expression has been detected in a variety of preneoplastic or benign leisons, suggesting that re-expression of survivin may occur early during malignant transformation or following a disruption in the balance between cell division and apoptosis. Human survivin is a 142aa protein which migrates at ~16.5kD on SDS-PAGE gels. Multiple surviving splice variants have been described and therefore the molecular weight may vary according to the isoform(s) expressed. Described splice variants include: 1. Survivin-2B results insertion of an alternative exon. 2. Survivin-deltaEx3 results from the removal of exon 3. 3. Survivin-3B results from the addition of a novel exon 3B. 4. Survivin 2alpha consists of exon 1 and 2 and the acquisition of a new in-frame spot codon, predicting a truncated 74aa protein.
Applications:
Suitable for use in Western Blot, Immunohistochemistry and Immunoprecipitation. Other applications not tested.
Recommended Dilution:
Western Blot: 1:1000-1:2000
Immunohistochemistry (formalin fixed paraffin embedded): 1:1000-1:5000
Immunoprecipitation: 1:50-1:200
Immunohistochemistry: Frozen
Optimal dilutions to be determined by the researcher.
Positive Control:
Lymphoid, many cancer cell lines and tumor types
Storage and Stability:
May be stored at 4 degrees C for short-term only. Aliquot to avoid repeated freezing and thawing. Store at -20 degrees C. Aliquots are stable for at least 12 months. For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.