Adult mouse olfactory bulb floating section stained with RPCA-SCGN-AP, our rabbit polyclonal antibody to secretagogin in red (1:1,000 dilution) and chiken polyclonal antibody to calretinin: CPCA-Calretinin
(1: 1,000) in green. Secretagogin is predominantly expressed in cells in external plexiform lay (EPL) and granular cell lay (GCL) in olfactory bulb. Secretagogin coexists with calretinin in some cells in GCL, so these cells appear yellow. Secretagogin is found in both cell body and processes. Blue is a DNA stain.
Secretagogin is a member of the EF-hand (E-helix-loop-F-helix-hand) superfamily of calcium-binding proteins. It was first cloned from pancreatic islets of Langerhans and neuroendocrine cells and is highly expressed in theses tissues (1). Initially it is thought to be restricted to neuroendocrine cells, but it is now evident that secretagogin is expressed in numerous brain regions (2,3). The expression pattern of secretagogin is not conserved from rodents to humans. While human brain reveals an expression maximum in the cerebellum, in rat and mouse brain by far the highest expression of secretagogin is found in the olfactory bulb . Secretagogin has been shown to be involved in insulin secretion from pancreatic beta cells and is a strong candidate as a biomarker for endocrine tumors (4), and might be a useful biomarker for neuronal damage, stroke, and eventually psychiatric conditions (2,5-7). Moreover, secretagogin has been hypothesized to exert a neuroprotective role in neurodegenerative diseases like Alzheimer’s disease (8).
This antibody was raised against human secrtagogin protein expressed in and purified from E.coli.
1: Wagner L, Oliyarnyk O, Gartner W, Nowotny P, Groeger M, Kaserer K , Waldhausl W and Pasternack MS. Cloning and expression of secretagogin,a novel neuroendocrine-and pancreaticis let of Langerhans-specific Ca2+-bindingprotein. J. Biol.Chem. 275, 24740–24751 (2000).
2: Gartner W, Lang W, Leutmetzer F, Domanovits H , Waldhausl W, and Wagner L Cerebral expression and serum detectability of secretagogin, a recently cloned EF-hand Ca(2C)-binding protein. Cereb.Cortex 11, 1161–1169 (2001).
3: Mulder J, Zilberter M, Spence L,Tortoriello G ,Uhlen M ,Yanagawa Y, Aujard F, Hokfelt T, and Harkany T. Secretagogin is a Ca2+- binding protein specifying sub population soft elencephalic neurons. Proc.Natl.Acad.Sci.U.S.A. 106, 22492–22497 (2009).
4: Ilhan A, Neziri D, Maj M, Mazal PR, Susani M, Base W, Gartner W, and Wagner L. Expression of secretagogin in clear-cell renal cell carcinomasis associated with a high metastasis rate. Hum.Pathol. 420, 641–648 (2011)
5: Lai M, Lu B, Xing X., Xu E, Ren G, and Huang Q. Secretagogin, a novel neuroendocrine marker, has a distinct expression pattern from chromogranin A. Virchows Arch. 449, 402–409 (2006).
6: Adolf K ,Wagner L ,Bergh A, Stattin P, Ottosen P ,Borre M, Birkenkamp-Demtroder K, Orntoft TF ,and Torring N. (2007). Secretagogin is a new neuroendocrine marker in the human prostate. Prostate 67, 472–484 (2007).
7: Zurek J, and Fedora M. The usefulness of S100B, NSE, GFAP, NF-H, secretagogin and Hsp70 as a predictive biomarker of outcome in children with traumatic brain injury. ActaNeurochir.(Wien) 154, 93–103 (2012).
8: Maj M, Milenkovic I, Bauer J, Berggård T, Veit M, Ilhan-Mutlu A, Wagner L, Tretter V. Novel insights into the distribution and functional aspects of the calcium binding protein Secretagogin from studies on rat brain and primary neuronal cell culture. Front Mol Neurosci. 5.84 (2012).