Caspase 3

Caspase-3 is one of the most important players in apoptosis signaling. It is synthesized as an inactive 32 kDa pro-enzyme and upon direct activation by Caspase-8, -9 or -10, it gets processed into its active forms, the p17-20 and p10-12 subunits. The latter are responsible for the cleavage of PARP (poly ADP-ribose polymerase), actin and SREBP, which are associated with apoptosis [1].

Survivin is an anti-apoptotic protein which is the smallest protein within a large family of proteins including X-linked IAP, c-IAP1 and 2, IAP-like protein-2, melanoma IAP, NAIP, and Livin. Survivin is responsible for a wide range of basic cellular functions that include the cell cycle regulation, fetal development, cell migration, and tumor progression.

Cytochrome C is a small heme protein within the inner mitochondrial membrane responsible for carrying electrons within the respiratory transport chain.  Additionally, cytochrome c has also been identified as a player in programmed cell death (apoptosis). During the early phases of apoptotic death reactions, cytochrome c translocates from the mitochondria membrane into the cytoplasm and serves to trigger the apoptotic proteolytic cascade by activating caspase 3, through association with protease activating factor-1 (Apaf-1).

Cell death via apoptosis is a basic cellular function occurring through the cell death receptor family and their ligands which signal through downstream adaptor molecules and the caspase protease family. Caspases have a precursor form composed of a prodomain, and large and small catalytic subunit, and are activated through a cleavage adjacent to an aspartate to liberate units and allow formation of an a2b2 tetramer. Caspase 3 is a cytoplasmic caspase with two isoforms (one acts as a dominant negative inhibitor), and is involved in the activation cascade for apoptosis execution.

Caspase 9 (also termed ICE-LAP6, Mch6, Apaf-3) is a member of cysteine protease family of caspases and is encoded by the CASP9 gene in humans. Caspase-9 is involved in mitochondrial apoptosis pathway and is an initiator caspase.

Caspase 7 (also known as CASP7, Mch3, ICE-LAP3, CMH-1) is a member of caspase family of cysteine proteases. It is an apoptosis-related cystein peptidase encoded by the CASP7 gene in humans. CASP7 homologous sequences have been identified in nearly all mammals. Similar to Caspase 3, Caspase-7 is an effector caspase and plays a key role in apoptotic execution.

Apoptosis is one of the best-characterized phenomena in cellular and molecular biology. Not only is it essential for successful development, but its deregulation also leads to a number of human diseases, most notably cancer.

S100A6 antibodies detect a small calcium binding protein with 2 EF-hand structures and belongs to the S100 family. Calcium binding induces a conformational change of the protein which in turn permits its interaction with several target proteins. It is predominantly expressed in fibroblasts and epithelial cells and has been implicated in several cellular processes such as cell cycle progression, cytoskeleton rearrangement and exocytosis.

Heat Shock Proteins (HSPs) are a ubiquitous group of molecular chaperone proteins that have evolved unique mechanisms, within their host cells, to facilitate survival in hostile environments such as heat, oxidative (hypoxia), pH and cold.

The caspases are a group of cysteine protease enzymes essential to apoptosis, inflammation and necrosis. Caspase 3 has been identified as one of the key mediators of apoptosis.