Estradiol differentially modulates the exocytotic proteins SNAP-25 and munc-18 in pituitary gonadotrophs

Weiß, Jürgen; Hüller, Heike; Polack, Stephan; Friedrich, Michael W.; Diedrich, K.; Treeck, Oliver; Ortmann, O.

doi:10.1677/jme.1.02114

Cited by 15 publications

(8 citation statements)

References 34 publications

Supporting

Mentioning

Contrasting

Unclassified

Order By: Relevance

“…This E2 effect has been shown to be mediated by a membraneinitiated signaling pathway of E2 involving the G proteincoupled receptor 30 (1,40). Moreover, in rat pituitary cells, E2 can also regulate calcium signaling by affecting the expression of some calcium-binding proteins, such as SNAP25 (63) and parvalbumin (17). In teleost fish, E2 is known to induce an increase in circulating levels of vitellogenin (8,36), a calcium binding protein from the liver, and a parallel increase in blood plasma calcium (21,44).…”

Section: Discussionmentioning

confidence: 99%

Profiling neuroendocrine gene expression changes following fadrozole-induced estrogen decline in the female goldfish

Zhang

Popesku

Martyniuk

et al. 2009

Physiological Genomics

View full text Add to dashboard Cite

Teleost fish represent unique models to study the role of neuroestrogens because of the extremely high activity of brain aromatase (AroB; the product of cyp19a1b). Aromatase respectively converts androstenedione and testosterone to estrone and 17␤-estradiol (E2). Specific inhibition of aromatase activity by fadrozole has been shown to impair estrogen production and influence neuroendocrine and reproductive functions in fish, amphibians, and rodents. However, very few studies have identified the global transcriptomic response to fadrozole-induced decline of estrogens in a physiological context. In our study, sexually mature prespawning female goldfish were exposed to fadrozole (50 g/l) in March and April when goldfish have the highest AroB activity and maximal gonadal size. Fadrozole treatment significantly decreased serum E2 levels (4.7 times lower; P ϭ 0.027) and depressed AroB mRNA expression threefold in both the telencephalon (P ϭ 0.021) and the hypothalamus (P ϭ 0.006). Microarray expression profiling of the telencephalon identified 98 differentially expressed genes after fadrozole treatment (q value Ͻ0.05). Some of these genes have shown previously to be estrogen responsive in either fish or other species, including rat, mouse, and human. Gene ontology analysis together with functional annotations revealed several regulatory themes for physiological estrogen action in fish brain that include the regulation of calcium signaling pathway and autoregulation of estrogen receptor action. Real-time PCR verified microarray data for decreased (activin-␤A) or increased (calmodulin, ornithine decarboxylase 1) mRNA expression. These data have implications for our understanding of estrogen actions in the adult vertebrate brain.aromatase; microarray; fish; brain MAIN ESTROGENS estradiol-17␤ (E2) and estrone (E1) play fundamental regulatory roles in neuroendocrine and reproductive systems. Through binding to its nuclear estrogen receptors (nER)-␣ and nER-␤, E2 regulates transcriptional process of target genes whose promoters contain estrogen-responsive elements (ERE) (57). In addition to this classical nuclear action, E2 also has membrane actions in which a unique membrane receptor is utilized to rapidly activate a series of signaling pathways (52,70). Since the signaling pathway activation will ultimately influence the transcriptional activities of downstream transcription factors including nERs, membrane actions of E2 provide another mode to regulate genomic gene expression (70). Fish are unique models in which to study E2 action because there is high activity of the B-subtype aromatase (AroB; the product of cyp19a1b), the enzyme responsible for synthesizing E2 from testosterone (T), in the neuroendocrine brain, telencephalon (Tel) and hypothalamus (Hyp) (42). Moreover, in contrast to mammals where aromatase and nER are commonly expressed in neurons, current studies in fish and birds strongly suggest that AroB is exclusively expressed in radial glial cells and nER is mostly expressed in neurons (16,43). Thus, the local...

show abstract

Section: Discussionmentioning

confidence: 99%

Profiling neuroendocrine gene expression changes following fadrozole-induced estrogen decline in the female goldfish

Zhang

Popesku

Martyniuk

et al. 2009

Physiological Genomics

View full text Add to dashboard Cite

show abstract

“…Compelling evidence for this scenario exists-a Glut4 sequence implicated in Glut4 transport from the cell surface to a subdomain of the trans-Golgi network enriched in the t-SNAREs Syntaxins 6 and 16 has been reported (Shewan et al 2003). To date, no relationship between sex hormones and these molecules has been reported in insulin-dependent tissues, although it has been shown in αT3-1 cells that estradiol regulates expression and content of munc-18 (Weiss et al 2007), a protein involved in Glut4 mobilization (D´Andrea-Merrins et al 2007). Taken together, this again might indicate a possible role for 17β-estradiol in Glut4 translocation.…”

Section: Discussionmentioning

confidence: 99%

Chronic 17β-estradiol treatment improves skeletal muscle insulin signaling pathway components in insulin resistance associated with aging

Moreno

Ordóñez

Alonso

et al. 2009

AGE

View full text Add to dashboard Cite

Insulin resistance is a common feature of aging in both humans and rats. In the case of females, it seems to be related to loss of gonadal function, due mainly due to a decrease in plasma estrogen levels. Several causes have been postulated for this insulin resistance, among them changes in several steps of the insulin pathway. In view of these findings, the purpose of the present study was to examine the role of chronic 17β-estradiol treatment on insulin sensitivity during the aging process, and its effects on levels of the insulin-sensitive glucose transporter Glut4 (both total and plasma membrane localized), the interaction between p85α subunit of PI3-k and IRS-1, Tyr-and Ser-612 phosphorylation of IRS-1 levels, and Ser-473 phosphorylation of Akt. The present findings indicate that 17β-estradiol treatment is able to minimize the deleterious effect of aging on insulin sensitivity, at least at the level of plasma membrane localized Glut4. Nevertheless further research is needed to determine this conclusively.

show abstract

“…sGnRH protein and sGnRH precursor mRNA expression is distributed in the ON, OB, T, preoptic area, and connecting regions of all of them in both sexes of homing mature chum salmon (Kudo et al, 1996). In mammals, female rat GnRH neuroendocrine cells express the mRNAs and proteins for SNAP-25 and Munc-18 as major SNARE complex proteins (Weiss et al, 2007). Therefore, the similarity of expression patterns of homing salmon brain snap25s…”

Section: Discussionmentioning

confidence: 98%

Molecular characterization and gene expression of synaptosome-associated protein-25 (SNAP-25) in the brain during both seaward and homeward migrations of chum salmon Oncorhynchus keta

Abe

Minowa

Kudo

2018

Comparative Biochemistry and Physiology Part A: Molecular &

View full text Add to dashboard Cite

It is generally accepted that information about some of the odorants in the natal streams of anadromous Pacific salmon (Genus Oncorhynchus) is imprinted during their seaward migration, and that anadromous Pacific salmon use olfaction to identify their natal streams during the homeward migration. However, little is known about the molecular mechanisms of the various pre-synaptic functions that are important for olfactory imprinting and memory retrieval in the salmon brain. Synaptosome-associated protein-25 (SNAP-25) mediates pre-synaptic vesicle exocytosis and regulates synaptic transmission and neuronal plasticity. Despite the importance of synaptic plasticity for memorization, the expression of SNAP-25 in the salmon brain is not well understood. In this study, snap25 expression was detected in chum salmon (O. keta) brains using molecular biological techniques. Two cDNAs encoding salmon SNAP-25 were isolated and sequenced (SNAP-25a and SNAP-25b). These cDNAs encoded proteins with 204 amino acid residues, which showed marked homology with each other (97%). The protein and nucleotide sequences demonstrated a high level of homology between salmon SNAP-25s and those of other teleost species. By quantitative PCR, the expression of snap25a and snap25b was detected in all regions of the salmon brain, especially in the telencephalon. The expression levels of snap25a in the olfactory blub were higher during seaward migration than in upriver and post-upriver migrations, reflecting synaptogenesis in the olfactory nervous system, and snap25b in the telencephalon was increased during upriver period. Our results indicated that snap25s gene is involved in synaptic plasticity for olfactory imprinting and/or olfactory memory retrieval in Pacific salmon.

show abstract

Estradiol differentially modulates the exocytotic proteins SNAP-25 and munc-18 in pituitary gonadotrophs

Cited by 15 publications

References 34 publications

Profiling neuroendocrine gene expression changes following fadrozole-induced estrogen decline in the female goldfish

Profiling neuroendocrine gene expression changes following fadrozole-induced estrogen decline in the female goldfish

Chronic 17β-estradiol treatment improves skeletal muscle insulin signaling pathway components in insulin resistance associated with aging

Molecular characterization and gene expression of synaptosome-associated protein-25 (SNAP-25) in the brain during both seaward and homeward migrations of chum salmon Oncorhynchus keta

Contact Info

Product

Resources

About