Techniques in Neuropeptide Processing, Trafficking, and Secretion

Cawley, Niamh X
Yanık, Tülin
Loh, Y Peng
Arnatuova, Irina
Lou, Hong
Patel, Nimesh
Neuropeptides function as neurotransmitters and neuromodulators. They are synthesized as larger precursors at the rough endoplasmic reticulum (RER), trafficked to the trans-Golgi network (TGN), and sorted into granules of the regulated secretory pathway (RSP) for secretion in an activity-dependent manner. Polymorphisms found in human neuropeptide genes can lead to defects in trafficking and processing of the neuropeptide precursors, resulting in disease. Examples of mutations of human neuropeptide genes that have led to biosynthesis of precursors that were misrouted and only partially processed include insulin (1), and cocaine and amphetamine-regulated transcript (CART) peptide (2), giving rise to diabetes and obesity, respectively. A human valine to methionine mutation in the prodomain of brain-derived neurotrophic factor (BDNF) causes its inefficient sorting to the RSP and diminished activity-dependent secretion of BDNF from hippocampal neurons, resulting in memory deficits in these humans (3). With the sequencing of the human genome, increasing numbers of polymorphisms in neuropeptide genes will be identified. Studies on the trafficking, processing, and activity-dependent secretion of the mutant neuropeptide precursors will be useful in elucidating the molecular and cellular basis of diseases associated with the mutations. There are currently many paradigms and tools to study neuropeptide precursor trafficking, processing, and secretion, and these will be described in this chapter. These procedures are also applicable to studying the processing of other proteins such as neurotrophins.


A Structural Perspective on the Modulation of Protein-Protein Interactions with Small Molecules.
Demirel, Habibe Cansu; Dogan, Tunca; Tunçbağ, Nurcan (2018-01-01)
Protein-Protein Interactions (PPIs) are the key components in many cellular processes including signaling pathways, enzymatic reactions and epigenetic regulation. Abnormal interactions of some proteins may be pathogenic and cause various disorders including cancer and neurodegenerative diseases. Although inhibiting PPIs with small molecules is a challenging task, it gained an increasing interest because of its strong potential for drug discovery and design. The knowledge of the interface as well as the stru...
Identification of interaction sites of G protein-coupled receptors using machine learning techniques
Şahin, Mehmet Emre; Can, Tolga; Department of Computer Engineering (2014)
G protein-coupled receptors (GPCRs), which play a crucial role in a host of pathophysiological pathways, form the largest and most divergent receptor family. Typically, they transmit outer signals to the inner cell by interacting with G-proteins. The emerging concept of GPCR dimerization has unsettled the classical idea that GPCRs function as monomeric units. Prediction of the interface residues of GPCR dimers is a challenging topic. The method proposed in this thesis trains itself with known interfaces fro...
More than just a dimer: detection of G protein-coupled receptor oligomers using fluorescent protein reassembly of Ste2p, a yeast pheromone receptor
Cevheroğlu, Orkun; Son, Çağdaş Devrim; Akkaya, Mahinur S.; Department of Biotechnology (2015)
GPCRs are known to form homo- and hetero-dimers and this interaction could have important roles in internalization, maturation, function and/or pharmacology of these receptors. In the first part of the study bimolecular fluorescence complementation (BiFC) using split enhanced green fluorescent protein (EGFP) was used to determine the interaction and cellular location between various Ste2p constructs. Co-expression of two constructs, one with the N-terminus of EGFP inserted into the full-length receptor at t...
Interactions between G-protein Coupled Receptors and Ligand Gated Ion Channels (GPCR-LGIC COUPLING)
Son, Çağdaş Devrim(2014-9-30)
Dopamine receptors are members of G-protein coupled receptor superfamily. These receptors are the key point of dopaminergic system, which controls the regulation of memory, attention, food intake, endocrine regulation, psychomotor activity and positive reinforcement. To regulate so many critically important neurological events, dopamine receptors have complex interactions with other receptors and ion channels. In this study, a trimeric complex comprising D2 receptor -which is a subtype of dopamine receptors...
A brighter method to illuminate the dark side of adhesion G protein-coupled receptors: detection of the ADGRG1 dimers by Bioluminescence Resonance Energy Transfer (BRET)
Murat, Merve; Son, Çağdaş Devrim; Cevheroğlu, Orkun; Department of Molecular Biology and Genetics (2021-9-7)
G protein-coupled receptors (GPCRs) form oligomeric complexes in living cells, and these complex structures affect the receptor maturation, trafficking, and signaling processes. Adhesion G protein-coupled receptors (aGPCRs), the second-largest sub-family of GPCRs, interact with extracellular matrix and ligands on the adjacent cell surface to modulate tissue and organ development. However, it is still unclear whether aGPCRs interact with each other. In this study, ADGRG1 was used as a model aGPCR to investi...
Citation Formats
N. X. Cawley, T. Yanık, Y. P. Loh, I. Arnatuova, H. Lou, and N. Patel, Techniques in Neuropeptide Processing, Trafficking, and Secretion. 2007, p. 96.