Mouse Calretinin Monoclonal Antibody | anti-CALB2 antibody
Calretinin
IHC: 1:2,000-5,000
WB: 1:2,000-1:5,000
HGNC name for this protein is CALB2
1. Draw of culture medium with aspirator and add 1 mL of 3.7 % formalin in PBS solution to the dish. (make up from 10 mLs Fisher 37% formalin plus 90mls PBS, the Fisher formalin contains 37% formaldehyde plus about 1% methanol which may be relevant sometimes). Let sit at room temp for 1 minute. (can add 0.1% Tween 20 to PBS used here and all subsequent steps to reduce background; probably best not to do this first time round though as it may extract your antigen or help wash your cells off the dish).
2. Take off the formalin/PBS and add 1ml of cold methanol (-20 degree C, kept in well-sealed bottle in fridge). Let sit for no more than 1 minute.
3. Take off methanol and add 1ml of PBS, not letting the specimen dry out. To block nonspecific antibody binding can add ~10 muL (=1%) of goat serum (Sigma), and can incubate for 30 minutes. Can then add antibody reagents. Typically, 100 muL of hybridoma tissue culture supernatent or 1ml of mouse ascites fluid or crude serum. Incubate for 1 hour at room temp. (or can go at 37 degree C for 30 minutes to 1 hour, or can do 4 degree C overnight, exact time not too critical). Can do very gentle shaking for well adherent cell lines (3T3, Hek293 etc.).
4. Remove primary antibody and replace with 1 mL of PBS. Let sit for 5-10 minutes, replace PBS and repeat twice, to give three washes in PBS.
5. Add 0.5 muLs of secondary antibody. These are fluorescently labeled Goat anti mouse or rabbit antibodies and are conjugated to ALEXA dyes and were originally marketed by Molecular Probes (Eugene Oregon, the ALEXA dyes are sulphonated rhodamine compounds and are much more stable to UV than FITC, TRITC, Texas red etc. Molecular Probes was bought by Invitrogen, which now markets these reagents). Typically make 1:2,000 dilutions of these secondaries in PBS plus 1% goat serum, BSA or non fat milk carrier. Incubate for 1 hour at room temp. (or can go at 37 degree C for 30 minutes to 1 hour, or can do 4 degree C overnight). Can do gentle shaking for well adherent cell lines (3T3, HEK293 etc.)
6. Remove secondary antibody and replace with 1 ml of PBS. Let sit for 5-10 minutes, replace PBS and repeat twice, to give three washes in PBS.
7. Drop on one drop of Fisher mounting medium onto dish and apply 22 mm square coverslip. View in the microscope!
The antibody can be stored at 2 degree to 8 degree C for 1 month without detectable loss of activity. Avoid repeated freeze-thaw cycles.
Calretinin contains six EF-hand domains. Four of them bind Ca2+ with high affinity in a cooperative manner, one with low affinity and the last one is non-functional, without Ca2+ -binding ability. The function of calretinin appears to be primarily buffering the Ca2+ level in cells and affect intracellular calcium signals. Calretinin deficiency in mossy cells of the dentate gyrus and granule cells results in abnormal excitability in the cerebellar neuronal network and impairment of long-term potentiation and motor coordination.
NCBI and Uniprot Product Information
Uniprot Description
Calretinin is a calcium-binding protein which is abundant in auditory neurons.