Calcium (Ca+2 or Ca) is the most abundant cation and it is required for many physiological activities such as bone formation and it acts as a second messenger in signal transduction.
However only 1% of Ca is present in ionic form in biological fluids.
Ca concentration is regulated by calcitropic hormones that act on bone, kidney, and intestine.
Extracellular Ca+-levels are sensed and regulated by Calcium Sensing receptor (CASR).
When Ca levels are limiting then it must be taken up by active, transcellular pathways comprising (1) Ca++ entry across apical membrane, (2) cytosolic transport of Ca++ across the cell form apical to basolateral membrane facilitated by a family of low mol wt Calcium binding proteins (CABPs) that include vitamin D3-dependent Ca++ binding proteins (calbindin-D9k, Calbindin-28k, Calretinin, Parvalbumin, S100, calmodulin) and finally (3) an active extrusion of Ca++ through basolateral membrane mediated by Ca++-ATPase and Na+-Ca++ exchangers (NCX).
Ca++ absorption in intestine and its reabsorption in kidney are carried out by Ca++ Transport (CaT) proteins, CaT-1, CaT-2 or Epithelial Ca Channel (ECAC1/ECAC2/CaT-Like (CaT-L) proteins.
Calbindins are Ca-binding proteins belonging to the troponin C superfamily.
There are two types of CaBPs: the "trigger"- and the "buffer"-CaBPs.
The conformation of "trigger" type CaBPs changes upon Ca2+ binding and exposes regions on protein that interact with target molecules, thus altering their activity.
The buffer-type CABP are thought to control the intracellular calcium concentration.
Calretinin/CR/CLB2/CALB2/Calbindin D29K protein (mouse/rat/human 271 aa, chromosome 16q22.1, mol wt ~29kD) also belongs to the Calbindin family.
It is most closely related to CABP28K (~55% identity).
It may be alternatively spliced to a C-terminally truncated fragment, Calretinin-22K in some tumor cell lines.
Calretinin is highly expressed in the cerebellum, olfactory bulb, and in auditory neurons.
Calretinin gene inactivation in mice eliminated long-term potentiation induction in the gentate gyrus and impaired motor coordination.
Applications:Suitable for use in ELISA, Western Blotting.
Other applications not tested.
Recommended Dilution:Western Blot: 1:2K-5K) for antiserum using Chemiluminescence technique.
CR is ~31kD.
ELISA: 1:10,000-1:100,000 using 50-100ng of control peptide/well.
Optimal dilutions to be determined by the researcher.
Storage and Stability:May be stored at 4°C for short-term only.
For long-term storage and to avoid repeated freezing and thawing, aliquot and add glycerol (40-50%).
Freeze at -20°C.
Aliquots are stable for at least 12 months at -20°C.
For maximum recovery of product, centrifuge the original vial after thawing and prior to removing the cap.
Further dilutions can be made in assay buffer.
仕様
Size：100ul
Host：goat
Source Antibody：guinea pig
Grade：Serum
Purity：Serum
Form：Supplied as a lyophilized powder from PBS, 0.05% sodium azide.
Specificity：Reacts with g. porcine, human, mouse and rat CR. No significant reactivity is seen with other CABPs. Antibody reactivity in various other species is not known
