Somatostatin Receptor 3 Antibodies

The somatostatin receptor 3 (SST3) is highly expressed in the anterior pituitary and many neuroendocrine tumors including non-functioning pituitary adenomas (NFA). It is a promising target for multireceptor somatostatin analogs. The SST3 receptor is unique among somatostatin receptors in that it exhibits a very long intracellular carboxyl-terminal tail. SST3 desensitization, β-arrestin recruitment and internalization are entirely regulated by phosphorylation of phosphate acceptor sites in the proximal portion of its carboxyl-terminal tail including serine337/threonine341 (pS337/pT341-SST3) and threonine348 (pT348-SST3). This nomenclature refers to the human SST3. Agonist-induced phosphorylation of S337/T341 and T348 is mediated by GRK2 and GRK3. SST3 dephosphorylation is primarily mediated by protein phosphatases 1 alpha and beta (PP1α/β). For more information on SST3 pharmacology please refer to the IUPHAR database. For further reading refer to:

Lehmann A, Kliewer A, Günther T, Nagel F, Schulz S. Identification of Phosphorylation Sites Regulating sst3 Somatostatin Receptor Trafficking. Mol Endocrinol. 2016 Jun;30(6):645-59. doi: 10.1210/me.2015-1244. Epub 2016 Apr 21. PubMed PMID: 27101376; PubMed Central PMCID: PMC5414643.

Kliewer A, Mann A, Petrich A, Pöll F, Schulz S. A transplantable phosphorylation probe for direct assessment of G protein-coupled receptor activation. PLoS One. 2012;7(6):e39458. doi: 10.1371/journal.pone.0039458. Epub 2012 Jun 26. PubMed PMID: 22745760; PubMed Central PMCID: PMC3383726.

Tulipano G, Stumm R, Pfeiffer M, Kreienkamp HJ, Höllt V, Schulz S. Differential beta-arrestin trafficking and endosomal sorting of somatostatin receptor subtypes. J Biol Chem. 2004 May 14;279(20):21374-82. Epub 2004 Mar 4. PubMed PMID: 15001578.