Read by QxMD icon Read


Corinne Beier, Anahit Hovhannisyan, Sydney Weiser, Jennifer Kung, Seungjun Lee, Dae Yeong Lee, Philip Huie, Roopa Dalal, Daniel Palanker, Alexander Sher
Upon degeneration of photoreceptors in the adult retina, interneurons, including bipolar cells, exhibit a plastic response leading to their aberrant rewiring. Photoreceptor reintroduction has been suggested as a potential approach to sight restoration, but the ability of deafferented bipolar cells to establish functional synapses with photoreceptors is poorly understood. Here we use photocoagulation to selectively destroy photoreceptors in adult rabbits, while preserving the inner retina. We find that rods and cones shift into the ablation zone over several weeks, reducing the blind spot at scotopic and photopic luminances...
April 3, 2017: Journal of Neuroscience: the Official Journal of the Society for Neuroscience
Mourad Ferdaoussi, Jianyang Fu, Xiaoqing Dai, Jocelyn E Manning Fox, Kunimasa Suzuki, Nancy Smith, Gregory Plummer, Patrick E MacDonald
Insulin secretion from pancreatic ß cells is a multistep process that requires the coordination of exocytotic proteins that integrate diverse signals. These include signals derived from metabolic control of post-translational SUMOylation and depolarization-induced rises in intracellular Ca(2+). Here we show that tomosyn, which suppresses insulin exocytosis by binding syntaxin1A, does so in a manner which requires its SUMOylation. Glucose-dependent de-SUMOylation of tomosyn1 at K298 releases syntaxin1A and controls the amplification of exocytosis in concert with a recently-identified tomosyn1-interacting partner; the Ca(2+)-binding protein secretagogin, which dissociates from tomosyn1 in response to Ca(2+)-raising stimuli and is required for insulin granule trafficking and exocytosis downstream of Ca(2+) influx...
March 21, 2017: Scientific Reports
János Hanics, Edit Szodorai, Giuseppe Tortoriello, Katarzyna Malenczyk, Erik Keimpema, Gert Lubec, Zsófia Hevesi, Mirjam I Lutz, Márk Kozsurek, Zita Puskár, Zsuzsanna E Tóth, Ludwig Wagner, Gábor G Kovács, Tomas G M Hökfelt, Tibor Harkany, Alán Alpár
The rostral migratory stream (RMS) is viewed as a glia-enriched conduit of forward-migrating neuroblasts in which chemorepulsive signals control the pace of forward migration. Here we demonstrate the existence of a scaffold of neurons that receive synaptic inputs within the rat, mouse, and human fetal RMS equivalents. These neurons express secretagogin, a Ca(2+)-sensor protein, to execute an annexin V-dependent externalization of matrix metalloprotease-2 (MMP-2) for reconfiguring the extracellular matrix locally...
March 7, 2017: Proceedings of the National Academy of Sciences of the United States of America
Toshio Kosaka, Seiko Yasuda, Katsuko Kosaka
In the rat striatum numerous secretagogin (SCGN) positive neurons were scattered. They were heterogeneous in their morphological and chemical properties. We examined the colocalization of SCGN with known four interneuron markers, parvalbumin (PV), calretinin (CR), nitric oxide synthase (NOS) and choline acetyl transferase (ChAT). 60-70% of SCGN positive striatal neurons contained either PV or CR or ChAT, but none contained NOS. On the other hand the remaining 30-40% expressed none of these markers, most of which were GAD positive...
February 10, 2017: Neuroscience Research
Roman A Romanov, Alan Alpar, Tomas Hökfelt, Tibor Harkany
Hormonal responses to acute stress rely on the rapid induction of corticotropin-releasing hormone (CRH) production in the mammalian hypothalamus, with subsequent instructive steps culminating in corticosterone release at the periphery. Hypothalamic CRH neurons in the paraventricular nucleus of the hypothalamus are therefore considered "stress neurons". However, significant morphological and funtional diversity amongst neurons that can transiently produce CRH in other hypothalamic nuclei has been proposed, particularly since histochemical evidence associates CRH to both GABA and glutamate neurotransmission...
January 5, 2017: Journal of Endocrinology
Radhika Khandelwal, Anand Kumar Sharma, Swathi Chadalawada, Yogendra Sharma
Secretagogin (SCGN), a multifunctional, Ca(2+) binding, regulatory protein, known to regulate insulin release, has recently been implicated in the control of stress-related corticotropin-releasing hormone (CRH) secretion. Localization of SCGN to multiple intracellular (such as cytosol, nucleus, and endoplasmic reticulum) and extracellular sites appears to provide multifunctional capabilities; however, the structural elements conferring such a widespread cellular distribution to SCGN remain unidentified. We report that the spatial and functional attributes of SCGN plausibly originate from the interplay between Ca(2+) and its redox state...
January 5, 2017: Biochemistry
Kalyani Sanagavarapu, Tanja Weiffert, Niamh Ní Mhurchú, David O'Connell, Sara Linse
Secretagogin is a calcium-sensor protein with six EF-hands. It is widely expressed in neurons and neuro-endocrine cells of a broad range of vertebrates including mammals, fishes and amphibia. The protein plays a role in secretion and interacts with several vesicle-associated proteins. In this work, we have studied the contribution of calcium binding and disulfide-bond formation to the stability of the secretagogin structure towards thermal and urea denaturation. SDS-PAGE analysis of secretagogin in reducing and non-reducing conditions identified a tendency of the protein to form dimers in a redox-dependent manner...
2016: PloS One
Farid N Garas, Rahul S Shah, Eszter Kormann, Natalie M Doig, Federica Vinciati, Kouichi C Nakamura, Matthijs C Dorst, Yoland Smith, Peter J Magill, Andrew Sharott
Corticostriatal afferents can engage parvalbumin-expressing (PV+) interneurons to rapidly curtail the activity of striatal projection neurons (SPNs), thus shaping striatal output. Schemes of basal ganglia circuit dynamics generally consider striatal PV+ interneurons to be homogenous, despite considerable heterogeneity in both form and function. We demonstrate that the selective co-expression of another calcium-binding protein, secretagogin (Scgn), separates PV+ interneurons in rat and primate striatum into two topographically-, physiologically- and structurally-distinct cell populations...
September 26, 2016: ELife
Seo-Yun Yang, Jae-Jin Lee, Jin-Hee Lee, Kyungeun Lee, Seung Hoon Oh, Yu-Mi Lim, Myung-Shik Lee, Kong-Joo Lee
Secretagogin (SCGN), a Ca(2+)-binding protein having six EF-hands, is selectively expressed in pancreatic β-cells and neuroendocrine cells. Previous studies suggested that SCGN enhances insulin secretion by functioning as a Ca(2+)-sensor protein, but the underlying mechanism has not been elucidated. The present study explored the mechanism by which SCGN enhances glucose-induced insulin secretion in NIT-1 insulinoma cells. To determine whether SCGN influences the first or second phase of insulin secretion, we examined how SCGN affects the kinetics of insulin secretion in NIT-1 cells...
June 15, 2016: Biochemical Journal
Qin Liu, Maode Lai
Secretagogin (SCGN) is a novel member of EF-hand Ca2+-binding proteins, which was identified in islet β cells by Wagner. SCGN is a six EF-hand Ca2+-binding protein, primarily expressed on the neuroendocrine axis and the central nervous system. The protein has abundant biological functions. A certain concentration of calcium ion can lead to conformation change of SCGN, resulting in the change of intracellular signal transduction. Preliminary studies showed that SCGN would be used to treat stress reaction, such as mental illness (depression), burns or post-traumatic stress disorder and chronic stress reaction caused by pain...
January 2016: Zhejiang da Xue Xue Bao. Yi Xue Ban, Journal of Zhejiang University. Medical Sciences
Fangying Xu, Qin Liu, Fengyan Han, Enping Xu, Maode Lai, Zhongsheng Zhao
OBJECTIVE: To investigate the association of neuroendocrine differentiation with progression and prognosis of gastric adenocarcinoma. METHODS: Clinicopathological data of 240 patients with gastric adenocarcinomas were retrospectively analyzed. The expression of chromogranin A, synaptophysin and secrectagogin in cancer tissue was assessed by immunohistochemistry. The association of neuoroendocrine differentiation parameters with disease progression and survival of patients was analyzed...
January 2016: Zhejiang da Xue Xue Bao. Yi Xue Ban, Journal of Zhejiang University. Medical Sciences
Masaki Kobayashi, Eiji Yamato, Koji Tanabe, Fumi Tashiro, Satsuki Miyazaki, Jun-ichi Miyazaki
Elucidating the regulation of glucose-stimulated insulin secretion (GSIS) in pancreatic β cells is important for understanding and treating diabetes. The pancreatic β cell line, MIN6, retains GSIS but gradually loses it in long-term culture. The MIN6 subclone, MIN6c4, exhibits well-regulated GSIS even after prolonged culture. We previously used DNA microarray analysis to compare gene expression in the parental MIN6 cells and MIN6c4 cells and identified several differentially regulated genes that may be involved in maintaining GSIS...
2016: PloS One
Orsolya Kántor, Szilvia Mezey, Jennifer Adeghate, Angela Naumann, Roland Nitschke, Anna Énzsöly, Arnold Szabó, Ákos Lukáts, János Németh, Zoltán Somogyvári, Béla Völgyi
Ca(2+)-buffer proteins (CaBPs) modulate the temporal and spatial characteristics of transient intracellular Ca(2+)-concentration changes in neurons in order to fine-tune the strength and duration of the output signal. CaBPs have been used as neurochemical markers to identify and trace neurons of several brain loci including the mammalian retina. The CaBP content of retinal neurons, however, varies between species and, thus, the results inferred from animal models cannot be utilised directly by clinical ophthalmologists...
July 2016: Cell and Tissue Research
Chuang Lyu, Jan Mulder, Swapnali Barde, Kristoffer Sahlholm, Hugo Zeberg, Johanna Nilsson, Peter Århem, Tomas Hökfelt, Kaj Fried, Tie-Jun Sten Shi
BACKGROUND: Increased nociceptive neuronal excitability underlies chronic pain conditions. Various ion channels, including sodium, calcium and potassium channels have pivotal roles in the control of neuronal excitability. The members of the family of G protein-gated inwardly rectifying potassium (GIRK) channels, GIRK1-4, have been implicated in modulating excitability. Here, we investigated the expression and distribution of GIRK1 and GIRK2 in normal and injured dorsal root ganglia (DRGs) and spinal cord of rats...
2015: Molecular Pain
Anand Kumar Sharma, Radhika Khandelwal, Yogendra Sharma, Vangipurapu Rajanikanth
Secretagogin (SCGN), a hexa EF-hand calcium-binding protein, is highly expressed in the endocrine cells (especially in pancreatic islets) and in restricted neuronal sub-populations, albeit at comparatively low level. Since SCGN is predicted to be a potential neuroendocrine marker in carcinoid tumors of lung and gastrointestinal tract, it is of paramount importance to understand the features of this protein in different environment for assigning its crucial functions in different tissues and under pathophysiological conditions...
May 2015: Protein Expression and Purification
Roman A Romanov, Alán Alpár, Ming-Dong Zhang, Amit Zeisel, André Calas, Marc Landry, Matthew Fuszard, Sally L Shirran, Robert Schnell, Árpád Dobolyi, Márk Oláh, Lauren Spence, Jan Mulder, Henrik Martens, Miklós Palkovits, Mathias Uhlen, Harald H Sitte, Catherine H Botting, Ludwig Wagner, Sten Linnarsson, Tomas Hökfelt, Tibor Harkany
A hierarchical hormonal cascade along the hypothalamic-pituitary-adrenal axis orchestrates bodily responses to stress. Although corticotropin-releasing hormone (CRH), produced by parvocellular neurons of the hypothalamic paraventricular nucleus (PVN) and released into the portal circulation at the median eminence, is known to prime downstream hormone release, the molecular mechanism regulating phasic CRH release remains poorly understood. Here, we find a cohort of parvocellular cells interspersed with magnocellular PVN neurons expressing secretagogin...
January 2, 2015: EMBO Journal
Yifeng Bai, Yanqin Sun, Juan Peng, Hongzhan Liao, Hongyi Gao, Ying Guo, Linlang Guo
Secretagogin (SCGN) has recently been identified to play a crucial role in cell apoptosis, receptor signaling and differentiation. However, its clinical significance and functional roles in SCLC chemoresistance remain unknown. Here we examined the expression of SCGN in clinical samples from SCLC patients and evaluated its relation with clinical prognosis. Then up and down-regulation of SCGN were carried out in SCLC cell lines to assess its influence on chemoresistance. Furthermore, luciferase reporter assay was used to evaluate whether SCGN is a novel direct target of miR-494...
September 15, 2014: Oncotarget
Georgina Gáti, Dávid Lendvai, Tomas Hökfelt, Tibor Harkany, Alán Alpár
In the vertebrate nervous system, the Ca(2+)-binding proteins parvalbumin, calbindin and calretinin have been extensively used to elaborate the molecular diversity of neuronal subtypes. Secretagogin is a phylogenetically conserved Ca(2+)-binding protein, which marks neuronal populations largely distinct from other Ca(2+)-binding proteins in mammals. Whether secretagogin is expressed in nonmammalian vertebrates, particularly in birds, and, if so, with a brain cytoarchitectonic design different from that of mammals is unknown...
2014: Brain, Behavior and Evolution
Ming-Dong Zhang, Giuseppe Tortoriello, Brian Hsueh, Raju Tomer, Li Ye, Nicholas Mitsios, Lotta Borgius, Gunnar Grant, Ole Kiehn, Masahiko Watanabe, Mathias Uhlén, Jan Mulder, Karl Deisseroth, Tibor Harkany, Tomas G M Hökfelt
Neuronal calcium (Ca(2+))-binding proteins 1 and 2 (NECAB1/2) are members of the phylogenetically conserved EF-hand Ca(2+)-binding protein superfamily. To date, NECABs have been explored only to a limited extent and, so far, not at all at the spinal level. Here, we describe the distribution, phenotype, and nerve injury-induced regulation of NECAB1/NECAB2 in mouse dorsal root ganglia (DRGs) and spinal cord. In DRGs, NECAB1/2 are expressed in around 70% of mainly small- and medium-sized neurons. Many colocalize with calcitonin gene-related peptide and isolectin B4, and thus represent nociceptors...
March 25, 2014: Proceedings of the National Academy of Sciences of the United States of America
Katsuko Kosaka, Toshio Kosaka
Secretagogin (SCGN) is a recently discovered calcium binding protein of the EF hand family. We studied the structural features of SCGN-positive neurons in the mouse main olfactory bulb (MOB). SCGN-positive neurons were localized throughout layers but clustered in the glomerular layer (GL), mitral cell layer (MCL) and granule cell layer (GCL). They were heterogeneous, including numerous juxtaglomerular neurons, granule cells, small to medium-sized neurons in the external plexiform layer (EPL), and a few small cells in the ependymal/subependymal layer...
September 2013: Neuroscience Research
Fetch more papers »
Fetching more papers... Fetching...
Read by QxMD. Sign in or create an account to discover new knowledge that matter to you.
Remove bar
Read by QxMD icon Read

Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"