Synapsin (phospho Ser9) Antibody

Synapsin I plays a key role in synaptic plasticity in brain. This effect is due in large part to the ability of the synapsins to regulate the availability of synaptic vesicles for release. In addition to its role in plasticity, the expression of synapsin I is a precise indicator of synapse formation. Thus synapsin I immunocytochemistry provides a valuable tool for the study of synaptogenesis. The role of synapsin in synaptic plasticity and in synaptogensis is regulated by phosphorylation. Serine 9 is the site on synapsin I that is phosphorylated by cAMP-dependent protein kinase and by calcium calmodulin kinase I. Phosphorylation of this site is thought to regulate synaptic vesicle function.

Synapsin (Ser9) polyclonal antibody was raised against a synthetic phosphopeptide corresponding to amino acids residues surrounding the phosphorylated Ser9 of Rat Synapsin I.

For long term storage –80˚ C is recommended, but shorter term storage at –20˚ C is also acceptable as aliquots may be taken without freeze/thawing due to the presence of 50% glycerol. Stable for one year.

Immunolabeling of the 78k Synapsin I doublet in a Western blot of rat brain homogenate is blocked by the phosphopeptide used as antigen but not by the corresponding non-phosphopeptide. The antibody also weakly labels Synapsin II (55k) which has a similar phosphorylation site to that of Ser9 on Synapsin I. Applications include Dot Blots (DB) and Western Blots (WB) . Suitability for Immunohistochemistry (IHC) has not yet been determined. Human, mouse, rat and Xenopus have 100% amino acid sequence identity with the antigen used to raise the antibody. When internally tested under ideal conditions the working dilutions were 1:1000 for DB and WB.

Kao, H.T., Song, H.J., Porton, B., Ming, G.L., Hoh, J., Abraham, M., Czernik, A.J., Pieribone, V.A., Poo, M.M., and Greengard, P., "A protein kinase A-dependent molecular switch in synapsins regulates neurite outgrowth, " Nature Neurosci., 5 (2002) 431 - 437.

Jovanovic, J.N., Sihra, T.S., Nairn, A.C., Hemmings, H.C., Jr., Greengard, P., and Czernik, A.J., "Opposing changes in phosphorylation of specific sites in synapsin I during Ca2+-dependent glutamate release in isolated nerve terminals, " J. Neurosci., 21 (2001) 7944 - 7953.

Menegon, A., Dunlap, D.D., Castano, F., Benfenati, F., Czernik, A.J., Greengard, P., and Valtorta, F., "Use of phosphosynapsin I-specific antibodies for image analysis of signal transduction in single nerve terminals, " J. Cell Sci., 113 (2000) 3573 - 3582.

Hosaka, M, Hammer, R.E., Sudhof, T.C., "A phospho-switch controls the dynamic association of synapsins with synaptic vesicles, " Neuron, 24 (1999) 377-87.