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Markus Thamm Sabine Balfanz Ricarda Scheiner Arnd Baumann Wolfgang Blenau 《Cellular and molecular life sciences : CMLS》2010,67(14):2467-2479
Serotonin plays a key role in modulating various physiological and behavioral processes in both protostomes and deuterostomes.
The vast majority of serotonin receptors belong to the superfamily of G-protein-coupled receptors. We report the cloning of
a cDNA from the honeybee (Am5-ht1A) sharing high similarity with members of the 5-HT1 receptor class. Activation of Am5-HT1A by serotonin inhibited the production of cAMP in a dose-dependent manner (EC50 = 16.9 nM). Am5-HT1A was highly expressed in brain regions known to be involved in visual information processing. Using in vivo pharmacology,
we could demonstrate that Am5-HT1A receptor ligands had a strong impact on the phototactic behavior of individual bees. The data presented here mark the first
comprehensive study—from gene to behavior—of a 5-HT1A receptor in the honeybee, paving the way for the eventual elucidation of additional roles of this receptor subtype in the
physiology and behavior of this social insect. 相似文献
3.
T. Nakaki B. C. Wise D. M. Chuang R. Kato 《Cellular and molecular life sciences : CMLS》1989,45(9):879-881
Summary The effects of serotonin on the formation of inositol phosphates and protein phosphorylation were examined in cultured smooth muscle cells. Serotonin stimulated the formation of [3H]inositol monophosphate, [3H]inositol bisphosphate and [3H]inositol trisphosphate. This effect was prevented by 5-HT2 specific antagonist, 6-methyl-1-(1-methylethyl)ergoline-8-carboxylic acid, 2-hydroxy-1-methylpropyl ester [Z]-2-butenedioate (LY53857). Serotonin stimulated the phosphorylation of many polypeptides, among which a 20 kDa polypeptide was the most prominent. The phosphorylation was also inhibited by LY53857. LY53857 alone produced no effects on protein phosphorylation. The 20 kDa polypeptides were also phosphorylated by the addition of 12-O-tetradecanoylphorbol-13-acetate. These results suggest that serotonin stimulates protein phosphorylation through 5-HT2 receptors and possibly activates protein kinase C in intact vascular smooth muscle cells.Part of the data contained in this paper was presented at the 74th local meeting of the Japanese Society of Pharmacology at Kanagawa. 相似文献
4.
T. Matsuoka T. Nishizaki Y. Ikeuchi Y. Okada K. Sumino 《Cellular and molecular life sciences : CMLS》1997,53(3):233-236
Effects of serotonin (5-HT) on cerebral cortical neurons were examined by patch clamp techniques. 5-HT produced a variety
of responses such as outward (19/73 patches/neurons), slow inward (15/73 patches/neurons), fast inward (8/73 patches/neurons),
and mixed currents (initially fast inward deflection followed by an outward response: 2/73 patches/neurons), with a latency
of 12 sec, 15 sec, 0 sec, and 0 sec respectively, at a holding potential of −60 mV in whole-cell patches. The fast inward
currents were again evoked by a selective 5-HT3 receptor agonist, 1-(m-chlorophenyl)-biguanide hydrochloride (CPBG). In the
cell-attached patch clamp configuration, 5-HT inside the patch pipette elicited single channel currents with slope conductances
of 42 pS and 132 pS (4/42 patches/neurons). CPBG inside the patch pipette evoked inward single channel currents with a lower
slope conductance of 41 pS (3/23 patches/neurons). In contrast, application of 5-HT or a 5-HT2 receptor agonist, α-methyl-5-hydroxytryptamine-maleate, outside the patch pipette induced outward single channel currents with a major slope
conductance of 140 pS (8/30 patches/neurons) or 135 pS (6/20 patches/neurons), respectively. These results indicate that the
outward and fast inward currents may be mediated respectively by the 5-HT2 receptor, which is coupled to a G-protein, and by the 5-HT3 receptor, which contains the non-selective cation channel, and that the mixed type may be caused by both the 5-HT2 and 5-HT3 receptors.
Received 27 September 1996; received after revision 4 November 1996; accepted 7 November 1996 相似文献
5.
Zhang X Beaulieu JM Gainetdinov RR Caron MG 《Cellular and molecular life sciences : CMLS》2006,63(1):6-11
Many neuropsychiatric disorders are considered to be related to the dysregulation of brain serotonergic neurotransmission.
Tryptophan hydroxylase-2 (TPH2) is the neuronal-specific enzyme that controls brain serotonin synthesis. There is growing
genetic evidence for the possible involvement of TPH2 in serotonin-related neuropsychiatric disorders; however, the degree of genetic variation in TPH2 and, in particular, its possible functional consequences remain unknown. In this short review, we will summarize some recent
findings with respect to the functional analysis of TPH2.
Received 12 September 2005; received after revision 25 October 2005; accepted 31 October 2005 相似文献
6.
Summary 1st, 2nd, and early 3rd instarDrosophila larvae are extremely sensitive to 100% O2 or 75% O2/25% N2 (at atmospheric pressure) whereas eggs, late 3rd instar larvae, and pupae are relatively insensitive under our exposure conditions. Eclosing flies exposed to an O2 enriched environment consistently possessed 2 eye abnormalities: dark eye color and altered eye shape.Supported by NSF-URP grant SP1782684 and a Summer Faculty Fellowship to Harry Nickla. 相似文献
7.
Qiong Yang Zhong-Jun Gong Ying Zhou Jing-Qun Yuan Jiaan Cheng Lin Tian Sheng Li Xin-Da Lin Ruijuan Xu Zeng-Rong Zhu Cungui Mao 《Cellular and molecular life sciences : CMLS》2010,67(9):1477-1490
Ceramidases catalyze the hydrolysis of ceramides to generate sphingosine (SPH) and fatty acids, and ceramide metabolism is implicated in various biological responses in Drosophila melanogaster. Here we report the cloning, biochemical characterization, and functional analysis of a Drosophila alkaline ceramidase (Dacer). Dacer, a membrane-bound protein of 284 amino acids, shares homology with yeast and mammalian alkaline ceramidases. Overexpression of Dacer in High Five insect cells increases ceramidase activity in the alkaline pH range, indicating that Dacer is a bona fide alkaline ceramidase. Dacer mRNA is highly expressed in the midgut and at the pupal stage. An inactivation of Dacer by insertional mutagenesis increases the levels of ceramides in both Drosophila pupae and adult flies. Dacer inactivation increases Drosophila pre-adult development time, lifespan, and anti-oxidative stress capacity. Collectively, these results suggest that Dacer plays an important role in the Drosophila development and longevity by controlling the metabolism of ceramides. 相似文献
8.
S. A. Tanco N. V. Watson B. B. Gorzalka 《Cellular and molecular life sciences : CMLS》1993,49(3):238-241
Although 5-HT1 and 5-HT2 receptor activity is known to influence copulation, the effects of 5-HT3 receptor-selective drugs on sexual activity have yet to be systematically studied. The following experiments investigated the effects of the 5-HT3-selective antagonists MDL 72222, ondansetron and ICS 205-930 on female sexual behaviour; male rats were studied using ondansetron and granisetron. These compounds influenced neither male nor female copulatory behaviours, suggesting that 5-HT3 receptors contribute little to the modulation of sexual activity. 5-HT3 receptor antagonists block certain opioid-induced behaviours and opioids selectively inhibit sexual behaviours; therefore, the ability of ondansetron and ICS 205-930 to modify morphine-attenuated copulatory activity was also tested. While morphine inhibited copulation, 5-HT3 antagonists failed to reverse the effects. 相似文献
9.
Royet J 《Cellular and molecular life sciences : CMLS》2004,61(5):537-546
Over the past years, parallel studies conducted in mammals and flies have emphasized the existence of common mechanisms regulating the vertebrate and invertebrate innate immune systems. This culminated in the discovery of the central role of the Toll pathway in Drosophila immunity and in the implication of Toll-like receptors (TLRs)/interleukin-1(IL-1) in the mammalian innate immune response. In spite of clear similarities, such as shared intracellular pathway components, important divergences are expected between the two groups, whose last common ancestor lived more than half a billion years ago. The most obvious discrepancies lie in the mode of activation of the signalling receptors by microorganisms. In mammals, TLRs are part of protein complexes which directly recognize microbe-associated patterns, whereas Drosophila Toll functions like a classical cytokine receptor rather than a pattern recognition receptor. Recent studies demonstrate that members of the evolutionarily conserved peptidoglycan recognition protein family play an essential role in microbial sensing during immune response of Drosophila.Received 26 June 2003; received after revision 29 July 2003; accepted 25 August 2003 相似文献
10.
Summary In adult sheep, the frequency of the migrating motor complexes (MMC) was increased by the duodenal administration of methysergide, but not affected by other 5-HT1 or 5-HT2 antagonists. This reset of the MMC pattern at a faster rhythm suggests a selective action on the enteric neuronal serotoninergic mechanism modulating the pacing of the gut cyclic motor activity. 相似文献
11.
Sheng-Ming Wu Ya-Hui Huang Yi-Hsin Lu Ling-Fang Chien Chau-Ting Yeh Ming-Ming Tsai Chen-Hsin Liao Wei-Jan Chen Chia-Jung Liao Wan-Li Cheng Kwang-Huei Lin 《Cellular and molecular life sciences : CMLS》2010,67(11):1831-1843
The thyroid hormone T3 regulates differentiation, growth, and development. We demonstrated that methionine adenosyltransferase 1A (MAT1A) was positively regulated by T3 identified by cDNA microarray previously. The expression of the MAT1A was upregulated by T3 in hepatoma cell lines overexpressing thyroid hormone receptors (TRs). Additionally, these findings indicate that MAT1A may be regulated by CCAAT/enhancer binding protein (C/EBP). The critical role of the C/EBP binding sites was confirmed by the reporter or chromatin immuno-precipitation (ChIP) assay. In addition, C/EBP was upregulated in hepatoma cells after T3 treatment and ectopic expression of MAT1A inhibited cell migration and invasion in J7 hepatoma cells. Conversely, knockdown of MAT1A expression increased cell migration. Together, these findings suggest that the expression of the MAT1A gene is mediated by C/EBP and is indirectly upregulated by T3. Finally, TR was downregulated in a small subset of hepatocellular carcinoma cells concomitantly reduced the expression of C/EBPα and MAT1A. 相似文献
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Zusammenfassung Die biologische Wirksamkeit der Gibberelline A1 bis A10, A13 und A14 wurde bei der Einsetzung von Parthenokarpie inMalus sylvestris Mill. festgestellt. Die Gibberelline A4 und A7 waren sehr wirksam, A1, A2, A3, A9, A10, A13 und A14 waren von mittelmässiger Wirksamkeit, während A5, A6 und A8 waren unwirksam. Die mehr wirksamen Gibberelline besitzen, vom molekularen Standpunkt betrachtet, in der Stellung 7 keine OH-Gruppe.
On leave from Osaka Prefecture University, Osaka, Japan. 相似文献
On leave from Osaka Prefecture University, Osaka, Japan. 相似文献
13.
F. Conforto 《Cellular and molecular life sciences : CMLS》1948,4(10):382-383
Summary The Noetherian surfaceF
4
(3)
, which is represented on a plane by a linear 3 system ofC
9(A
1
3
A
2
3
A
3
3
A
4
3
A
5
3
A
6
3
A
7
3
A
8
3
A
9
2
A
10), possesses generally only one linear pencil of elliptic cubics. IfA
i (i=1, 2, , 9) are the basis points of aHalphen pencil ofC
9,A
10 is infinitely near toA
9, and in this caseF
4
(3)
is a not trivial example of such a surface with two pencils of elliptic cubics. 相似文献
14.
4-Hydroxynonenal-modified amyloid-beta peptide inhibits the proteasome: possible importance in Alzheimer's disease 总被引:3,自引:0,他引:3
Shringarpure R Grune T Sitte N Davies KJ 《Cellular and molecular life sciences : CMLS》2000,57(12):1802-1809
The amyloid β-peptide (Aβ) is a 4-kDa species derived from the amyloid precursor protein, which accumulates in the brains of patients with Alzheimer’s
disease. Although we lack full understanding of the etiology and pathogenesis of selective neuron death, considerable data
do imply roles for both the toxic Aβ and increased oxidative stress. Another significant observation is the accumulation of abnormal, ubiquitin-conjugated proteins
in affected neurons, suggesting dysfunction of the proteasome proteolytic system in these cells. Recent reports have indicated
that Aβ can bind and inhibit the proteasome, the major cytoslic protease for degrading damaged and ubiquitin-conjugated proteins.
Earlier results from our laboratory showed that moderately oxidized proteins are preferentially recognized and degraded by
the proteasome; however, severely oxidized proteins cannot be easily degraded and, instead, inhibit the proteasome. We hypothesized
that oxidatively modified Aβ might have a stronger (or weaker) inhibitory effect on the proteasome than does native Aβ. We therefore also investigated the proteasome inhibitory action of Aβ
1–40 (a peptide comprising the first 40 residues of Aβ) modified by the intracellular oxidant hydrogen peroxide, and by the lipid peroxidation product 4-hydroxynonenal (HNE). H2O2 modification of Aβ
1–40 generates a progressively poorer inhibitor of the purified human 20S proteasome. In contrast, HNE modification of Aβ
1–40 generates a progressively more selective and efficient inhibitor of the degradation of fluorogenic peptides and oxidized
protein substrates by human 20S proteasome. This interaction may contribute to certain pathological manifestations of Alzheimer’s
disease
Received 26 September 2000; accepted 26 September 2000 相似文献
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Christian Piehl Jörg Piontek Jimmi Cording Hartwig Wolburg Ingolf E. Blasig 《Cellular and molecular life sciences : CMLS》2010,67(12):2131-2140
Tight junctions control paracellular permeability. Here, we analyzed the impact of residues in the second extracellular loop
(ECL2) of mouse claudin-5 on paracellular permeability. Stable expression of claudin-5wild type in MDCK-II cells—but not that of mutants R145A, Y148A, Y158A or E159Q—increased transepithelial electrical resistance and
decreased fluorescein permeation. Expression of claudin-5Y148A, Y158A or E159Q enhanced permeability of FITC-dextran10 kDa, which was unchanged in cells expressing claudin-5wild type or claudin-5R145A. In contrast, targeting to tight junctions, strand morphology and tight junction assembly were unchanged. It is concluded
that R145 is unessential for trans-interaction of claudin-5, but necessary for tightening against small solutes and ions. The highly conserved residues Y148,
Y158 and E159 in ECL2 of claudin-5 contribute to homo- and/or heterophilic trans-interaction between classic claudins and thereby tighten the paracellular space against ions, small and large molecules.
These results provide novel insights into the molecular function of tight junctions. 相似文献
17.
Groups of mice were maintained for up to 78 weeks on tryptophan restricted, protein restricted and control diets. Plasma tryptophan levels were significantly reduced by both forms of dietary restriction. Brain serotonin levels were significantly reduced only in mice on the tryptophan restricted diet, but not for mice on the protein restricted diet. The protein-restricted diet contains less of the large neutral amino acids which compete with tryptophan to enter the brain. It is known that protein restriction and tryptophan restriction extend lifespan. The results presented here suggest that extension of lifespan and lowering of brain serotonin are not related. 相似文献
18.
Summary Groups of mice were maintained for up to 78 weeks on tryptophan restricted, protein restricted and control diets. Plasma tryptophan levels were significantly reduced by both forms of dietary restriction. Brain serotonin levels were significantly reduced only in mice on the tryptophan restricted diet, but not for mice on the protein restricted diet. The protein-restricted diet contains less of the large neutral amino acids which compete with tryptophan to enter the brain. It is known that protein restriction and tryptophan restriction extend lifespan. The results presented here suggest that extension of lifespan and lowering of brain serotonin are not related. 相似文献
19.
Summary Seeds and fruit walls ofPharbitis purpurea contain in addition to the free gibberellins A8, A3, A5, more polar gibberellin-like substances, so-called bound gibberellins tentatively namedPharbitis and. After purification by thin layer chromatography, these 2 substances were treated with both Ficin and Emulsin in buffered solutions of pH 6.2. After treatment with Emulsin, the free gibberellins A8 and A5, after treatment with Ficin the gibberellins A3 and A5, were detectable in thin layer chromatograms. 相似文献
20.
G. Sembdner G. Schneider J. Weiland K. Schreiber 《Cellular and molecular life sciences : CMLS》1964,20(2):89-90
Summary In addition to gibberellins A1, A5, A6 and A8 previously isolated fromPhaseolus coccineus L., the occurrence of gibberellin A3 and of 5 new gibberellin-like substances «Phaseolus -» was demonstrated. «Phaseolus» was proved to be a gibberellin bound to carbohydrates and ninhydrin-positive compounds.
Gibberelline, II. Mitteilung. — I. Mitt. sieheG. Sembdner, R. Gross undK. Schreiber, Exper.18, 584 (1962). 相似文献
Gibberelline, II. Mitteilung. — I. Mitt. sieheG. Sembdner, R. Gross undK. Schreiber, Exper.18, 584 (1962). 相似文献