Bdnf Function And Intracellular Signaling In Neurons Pdf - The best free software for your11/30/2016 The kinesin, dynein, and myosin superfamily molecular motors have fundamental roles in neuronal function, plasticity, morphogenesis, and survival by transporting cargos such as synaptic vesicle precursors, neurotransmitter and. Taylor & Francis Group has acquired the Austin, TX based publisher Landes Bioscience.We are pleased to announce our latest list of journal titles which cover a range of topics, including genetics, cell biology, molecular. Hippocampal Ctsb Gene Expression and Analysis of CTSB Function (A) 30 days of running (R) increased hippocampal Ctsb mRNA levels compared to sedentary (S) controls. BDNF- induced LTP is associated with rapid Arc/Arg. Scientific Reports. Previous studies have shown that brief infusion of BDNF into the dentate gyrus induces LTP. In the present study, BDNF was infused immediately above the DG, 3. Previous immunohistochemical analysis of BDNF distribution showed rapid delivery of BDNF to the dorsal dentate gyrus (within < 1. BDNF infusion promotes the induction of LTP which lasts for at least 1. Accordingly, in the present experiment, BDNF infusion led to a robust increase in the f. Glial cells are currently viewed as active partners of neurons in synapse formation. The close proximity of astrocytes to the synaptic cleft implicates that they strongly influence synapse function as well as. BDNF acts on certain neurons of the central nervous system and the peripheral nervous system, helping to support the survival of existing neurons, and encourage the growth and differentiation of new neurons and. Notch proteins in postmitotic neurons. We first characterized the expression pattern of Notch receptors in postmitotic neurons. To gain the detection sensitivity of immunostaining, we took advantage of Notch1-Venus knock-in. Neurotrophins are a family of proteins that induce the survival, development, and function of neurons. They belong to a class of growth factors, secreted proteins that are capable of signaling particular cells to survive. Altmetric: 1; Views: 5,681; More detail. BDNF-induced LTP is associated with rapid Arc/Arg3.1-dependent enhancement in adult hippocampal neurogenesis. In the striatum, dopamine D1 receptors are preferentially expressed in striatonigral neurons, and increase the neuronal excitability, leading to the increase in GABAergic inhibitory output to substantia nigra pars reticulata. EPSP slope and population spike amplitude, an effect which was inhibited by Arc. AS infusion but not Arc. ASScr (Fig. Statistical analysis (general linear model for repeated measures) indicated a significant main effect of time (baseline vs infusion vs recording: F. Subsequent pair- wise comparisons (Sidak. The effect of BDNF infusion on LTP was completely inhibited by preceding Arc. AS administration (BDNF vs BDNF+Arc. AS, p. No differences were detected between Cyt. C and BDNF+Arc. AS- treated animals (Fig. These results show that infusion of exogenous BDNF in the DG was associated with the induction of robust LTP which requires the synthesis of new Arc protein. Blockage of Arc translation, through the administration of Arc AS (but not Arc ASScrambled) inhibited LTP induction. Figure 2: Time- course plot illustrating changes in perforant path- DG evoked f. EPSP slope expressed in percentage of baseline. Values are means. Cyt. C, BDNF, BDNF+Arc. AS and BDNF+Arc ASScr infusion points are indicated. Average field potential traces (1. BDNF) phases are shown. Representative photomicrographs illustrating Neu. N and Arc/Arg. 3. DG following unilateral BDNF infusion (BDNF- infused) or unilateral Cyt. C infusion (Cyt. C- infused). Total labeled (Id. U+ and Brd. U+) cells. Iodo- deoxy- Uridine (Id. U) and Bromo- deoxy- Uridine (Brd. U) are two thymidine analogs that integrate into cells undergoing DNA synthesis. Their incorporation into the DNA can be visualized through immunohistochemistry to provide an in vivo marker to identify proliferating cells. Id. U was given to adult male rats 2. Brd. U was administered 4. Importantly, the anti- Id. U antibody does not discriminate between Id. U and Brd. U, recognizing both analogs and labeling cells which have incorporated Id. U and/or Brd. U. In contrast, the anti- Brd. U antibody selectively detects Brd. U without cross- reacting with Id. U. As a result of primary antibody specificity, total number of labeled cells thus represents a combination of three distinct cell populations: Id. U(only)+ cells, Brd. U(only)+ and double Id. U+/Brd. U+ cells. Total labeled cells (Id. U(only)+ and Brd. U+) were quantified by light microscopy across the entire rostral- caudal extent of the hippocampus using serial sets of coronal sections (Fig. Two- way ANOVA was run to determine inter- hemispheric differences (BDNF infusion vs control side), treatment effects (Cyt. C vs BDNF vs BDNF+Arc. AS) and their interactions (treatment. Interestingly, although BDNF was infused in only one hemisphere, no differences in total labeled cell numbers were found between stimulated and non- stimulated sides in any hippocampal region examined (hilus, SGZ and GCL) (Fig. A significant main effect of treatment was found in the SGZ (F2,4. No effects were observed in the hilus or GCL. Figure 3. Total Id. U+ and Brd. U+ cells. Representative photomicrographs illustrating Id. U immunohistochemistry in the dentate gyrus following BDNF infusion (a, 4. Since the monoclonal anti- Id. U antibody used here could not discriminate between Id. U or Brd. U, it labeled all dividing Id. U+ and/or Brd. U+ cells. Total numbers of Id. U- labeled cells thus represent a combination of three distinct cell populations: Id. U+/Brd. U. Graph illustrating average total numbers of total labeled cells in the hippocampal hilus, subgranular zone (SGZ) and granule cell layer (GCL) per group (n. Graphs illustrating average numbers of labeled cells in the stimulated (BDNF- infused, d) and contralateral hemisphere (e). The * and $ symbols represent significant effects compared to Cyt. C- or BDNF- treated animals, respectively. One, two or three symbols represent p. Id. U(only)+, total Id. U+/Brd. U. High magnification images of inserts (e), illustrating a Brd. U+/Arc+/Neu. N+ cell (e. The latter images demonstrate that although Arc seems ubiquitously expressed in the DG, some Id. U+ and/or Brd. U+ cells were clearly Arc negative. Representative confocal photomicrographs depicting two different proliferating cells positive for Brd. U and/or Id. U (g. Our data showed a significant main effect of treatment in the SGZ (F2,4. Interestingly, no main effects were found between the infusion and the contralateral side (Fig. Post- hoc analysis revealed a significant increase of total Brd. U+ cells in the SGZ (BDNF vs Cyt. C, t. These results suggest that the increased bilateral numbers of Brd. U+ cells in response to unilateral BDNF infusion depended on BDNF- LTP induction. This was confirmed by the observation that unilateral infusion of Arc. AS blocked BDNF- induced pro- neurogenic actions, bilaterally. Figure 5. Graphs illustrating average total numbers of Brd. U+(Id. U. Graphs illustrating averages of total numbers of Id. U(only)+ or Id. U+/Brd. U- cells in the hippocampal hilus, subgranular zone (SGZ) and granule cell layer (GCL) per group (n. The * and + symbols represent significant effects compared to Cyt. C- or BDNF- treated animals, respectively. One, two or three symbols represent p. Id. U+ cells which re- divided in response to BDNF also incorporated Brd. U becoming double- positive (Id. U+ and Brd. U+) and, therefore, excluded from the Id. U(only)+ group. Results showed a significant main effect of treatment in the hilus (F2,4. No main inter- hemispheric effect was detected (Fig. In addition, a significant interaction was found between the treatment and infusion side in the hilus (F2,4. Post- hoc analysis indicated that BDNF infusion significantly reduced total Id. U(only)+ cells in the hilus (Cyt. C vs BDNF, t. In the GCL only, concurrent Arc. AS administration attenuated BDNF- mediated influences (BDNF+Arc. AS vs BDNF, t. In the hilus, BDNF- mediated effects on total Id. U(only)+ cells were mostly evident in the stimulated side (Cyt. C vs BDNF, t. These results indicate that BDNF stimulates the re- proliferation of NPCs which divided less than 2. As a consequence of this new BDNF- induced division, these cells incorporated Brd. U becoming double- positive (Id. U+ and Brd. U+) and resulting in a net reduction of the Id. U+/Brd. U. Under basal conditions, only a small percentage (less than 5%) of Brd. U+ cells in the DG is also positive for Arc. A significant main effect of treatment was found on Brd. U+/Arc+ cells in the hilus (F2,4. A significant main effect of stimulation side was also detected in the hilus (F1,4. Post- hoc analysis revealed that BDNF infusion increased Brd. U+/Arc+ cell numbers (BDNF vs. In the hilus, greater numbers of Brd. U+/Arc+ cells were found in the non- stimulated compared to the stimulated side in response to both BDNF (t. Figure 6. Graphs illustrating average total numbers of Id. U. Graphs illustrating average total numbers of Brd. U+/Arc. The * and + symbols represent significant effects compared to Cyt. C. One, two or three symbols represent p. No main effects of the stimulation side (Fig. Post- hoc analysis revealed a significant reduction of hilar Brd. U+/Arc. These findings indicate that unilateral BDNF infusion was associated with a bilateral increase in Brd. U+/Arc+ cells (possibly caused by BDNF- LTP), an effect which was blocked by unilateral Arc. AS infusion. In contrast, both BDNF and BDNF+Arc. AS infusion had no effects on the number of Brd. U+/Arc. With regard to total Id. U+/Brd. U. No main effects were detected between hemispheres (Fig. F2,4. 4. Post- hoc analysis revealed significantly increased numbers of Id. U+/BDNF. 7a). Figure 7. Graphs illustrating average total numbers of Id. U+/Brd. U. Graphs illustrating average total numbers of Id. U+/Brd. U- /Arc- cells in the hippocampal hilus, subgranular zone (SGZ) and granule cell layer (GCL) per group (n. The * and + symbols represent significant effects compared to Cyt. C- or BDNF- treated animals, respectively. One, two or three symbols represent p. No infusion effect was found between hemispheres in any region (Fig. F2,4. 4. Post- hoc analysis revealed that while BDNF significantly reduced total Id. U+/Brd. U. In the hilus, a significant reduction of Id. U+/Brd. U. 7e) but not the contralateral side. This effect was prevented by concurrent Arc. AS infusion (BDNF+Arc. AS vs BDNF, t. These results are similar to Brd. U+cells with the important difference that unilateral BDNF infusion was associated with a bilateral reduction in Id. U+/Brd. U. Remarkably, both BDNF and BDNF+Arc. AS infusion had no effects on the number of Id. U+/Brd. U. Brd. U was injected in Arc/Arg. We hypothesized that if Arc transcription was critical in hippocampal neurogenesis, Arc/Arg. Arc expression. If Arc involvement in hippocampal neurogenesis was limited to its role in the generation and maintenance of LTP, its effects on proliferation and/or survival would be limited as these mice were not stimulated (neither chemically with BDNF infusion nor behaviorally). Our data illustrate a significant reduction in the number of Brd. U- labeled cells between proliferation and survival experiments in the hilus (F1,2. Interestingly, no main effects of strain (wild- type vs Arc/Arg. Arc- mediated influences on hippocampal neurogenesis were indirect and linked to its role in the generation and maintenance of LTP. Figure 8: Total Brd. U- labeled cells in Arc/Arg. Representative photomicrographs illustrating Brd. U immunohistochemistry in the DG of wild- type and Arc/Arg. Graph illustrating average total numbers of Brd. U- labeled cells. The dopamine receptors are a superfamily of heptahelical G protein- coupled receptors, and are grouped into two categories, D1- like (D1, D5) and D2- like (D2, D3, D4) receptors, based on functional properties to stimulate adenylyl cyclase (AC) via Gs/olf and to inhibit AC via Gi/o, respectively (Kebabian and Calne, 1. Jackson and Westlind- Danielsson, 1. Missale et al., 1. In the striatum, dopamine D1 and D2 receptor expressions are segregated in two types of medium spiny neurons, striatonigral/direct and striatopallidal/indirect pathway neurons, respectively (Hersch et al., 1. Surmeier et al., 1. Valjent et al., 2. Bertran- Gonzalez et al., 2. In the striatonigral/direct pathway neurons, D1 receptors are coupled to Gs/olf/AC/PKA signaling, and activation of PKA induces the phosphorylation of PKA substrates such as DARPP- 3. AMP- regulated phosphoprotein of Mr 3. Da, and a transcription factor, CREB, leading to alterations of neuronal functions (Greengard et al., 1. Hyman and Malenka, 2. In this review, the roles of DARPP- 3. D1 receptor signaling and the recent findings on the modulation of D1 receptor/Gs/olf/AC/PKA signaling by phosphodiesterase (PDE) inhibitors are discussed. In addition, the non- canonical D1 receptor signaling cascades that couple to Gq/phospholipase C (PLC) or Src family kinase (SFK) are overviewed. Roles of DARPP- 3. Phosphorylation in D1 Receptor/Gs/olf/AC/c. AMP/PKA Signaling. Role of the PKA Phosphorylation- Site at Thr. DARPP- 3. 2Dopamine, acting on D1 receptors, stimulates c. AMP/PKA signaling via Gs/olf- mediated activation of AC (Herve et al., 2. In postsynaptic striatal neurons, DARPP- 3. AMP/PKA signaling cascade (Greengard et al., 1. Svenningsson et al., 2. DARPP- 3. 2 is expressed in D1 receptor- enriched striatonigral neurons as well as D2 receptor- enriched striatopallidal neurons (Bateup et al., 2. Phosphorylation at Thr. PKA converts DARPP- 3. PP- 1; Figure 1). The inhibition of PP- 1 thereby controls the phosphorylation state and activity of many downstream physiological effectors, including various neurotransmitter receptors (e. AMPA receptor Glu. R1 subunit, NMDA receptor NR1 subunit), ion channels and pumps (e. N/P- type Ca. 2+ channels, Na+ channel, Na+, K+- ATPase), and transcription factors (e. CREB, c- Fos, . Especially in cases of dual substrates for PKA and PP- 1 such as Glu. R1 at Ser. 84. 5 and NR1 at Ser. PKA signaling can efficiently increase the phosphorylation states of such substrates. Mice lacking DARPP- 3. DARPP- 3. 2 in dopaminergic signaling (Fienberg et al., 1. Fienberg and Greengard, 2. Recently, a study using DARPP- 3. DARPP- 3. 2 is selectively deleted in D1 receptor- enriched striatonigral or D2 receptor- enriched striatopallidal neurons, revealed that DARPP- 3. Bateup et al., 2. The loss of DARPP- 3. L- DOPA- induced dyskinesia in a 6- hydorxydopamine hemi- lesioned model of Parkinson’s disease, whereas the loss of DARPP- 3. These findings support the idea that DARPP- 3. D1 receptor functions in striatonigral neurons, but opposes D2 receptor functions in striatopallidal neurons. Figure 1. The D1 receptor signaling cascades in striatonigral/direct pathway neurons. D1 receptors couple to at least three distinct signaling cascades: (1) Gs/olf/adenylyl cyclase (AC)/c. AMP/PKA/DARPP- 3. PP- 1) signaling (blue; Svenningsson et al., 2. Stipanovich et al., 2. Gq/phospholipase C (PLC)/inositol 1,4,5- trisphosphate (IP3)/IP3 receptor/Ca. Rashid et al., 2. Kuroiwa et al., 2. Hasbi et al., 2. 00. G. The phosphorylation levels of DARPP- 3. Thr. 34 and high at Thr. Ser. 97, and Ser. Activation of PKA induces the phosphorylation of DARPP- 3. Thr. 34 and the dephosphorylation of DARPP- 3. Thr. 75 and Ser. 97 by PP- 2. A/B5. 6. ERK, activated by two D1 receptor pathways, induces mitogen- and stress- activated kinase 1 (MSK1) activation and histone H3 and c. AMP- response element binding protein (CREB) phosphorylation in the nucleus (Girault et al., 2. Pascoli et al., 2. Thus, D1 receptor- mediated activation of PKA, intracellular Ca. ERK signaling induces the changes in downstream signaling cascades and the transcriptional activation of many genes. Ca. MK, Ca. 2+/calmodulin- dependent protein kinase; DAG, diacylglycerol; PDE, phosphodiesterase; STEP, striatal- enriched tyrosine phosphatase. The phosphorylation state of DARPP- 3. Thr. 34 is regulated by the balance of phosphorylation by PKA and dephosphorylation by protein phosphatase 2. B (calcineurin) and 2. A (PP- 2. A). PKA signaling in direct pathway neurons is activated by . Dephosphorylation of phospho- Thr. DARPP- 3. 2 is mainly regulated by calcineurin (Nishi et al., 1. Activation of NMDA or AMPA receptors increases intracellular Ca. DARPP- 3. 2 at Thr. Halpain et al., 1. Nishi et al., 1. 99. D2 receptors are known to activate calcineurin via PLC/intracellular Ca. Hernandez- Lopez et al., 2. DARPP- 3. 2 at Thr. D1 and D2 receptors are co- expressed (Nishi et al., 1. PP- 2. A also contributes to control the dephosphorylation process of DARPP- 3. Thr. 34 in a coordinated manner with calcineurin, as inhibition of PP- 2. A and calcineurin induces the synergistic and robust increase in DARPP- 3. Thr. 34 phosphorylation in striatal slices (Nishi et al., 1. However, the role of PP- 2. A in the dephosphorylation of DARPP- 3. Thr. 34 is not fully understood under physiological conditions. Role of the Cdk. 5 Phosphorylation- Site at Thr. DARPP- 3. 2In addition to Thr. DARPP- 3. 2 is phosphorylated at multiple sites by several protein kinases. The major phosphorylation sites are at Thr. Cdk. 5; Bibb et al., 1. Ser. 97 for CK2 (Girault et al., 1. Ser. 13. 0 for CK1 (Desdouits et al., 1. DARPP- 3. 2 phosphorylated at Thr. PKA activity and thereby reduces the efficacy of dopamine D1 receptor signaling (Bibb et al., 1. Dopamine, via dopamine D1 receptors, activates PKA, which directly stimulates DARPP- 3. Thr. 34 phosphorylation, and indirectly stimulates DARPP- 3. Thr. 75 dephosphorylation by PP- 2. A (Nishi et al., 2. PP- 2. A associated with B5. The ability of activated PKA to reduce the phosphorylation state of DARPP- 3. Thr. 75 and thereby de- inhibit PKA is important as a positive feedback mechanism for enhancing PKA signaling (Nishi et al., 2. Further activation of PKA and inhibition of PP- 1 via DARPP- 3. Glutamate acting on NMDA or AMPA receptors also stimulates the dephosphorylation of DARPP- 3. Thr. 75 by PP- 2. A (Nishi et al., 2. PP- 2. A associated with B. PR7. 2 contains two Ca. EF hands, EF1 and EF2 (Janssens et al., 2. EF2 likely promotes the assembly of PP- 2. A/PR7. 2 complex, and Ca. EF1 activates PP- 2. A/PR7. 2 activity for DARPP- 3. Thr. 75 in a substrate- specific manner (Janssens et al., 2. Ahn et al., 2. 00. By utilizing the Ca. PP- 2. A/PR7. 2 pathway, glutamate increases PKA activity by dephosphorylating Thr. DARPP- 3. 2, similarly to the D1 receptor- activated PP- 2. A/B5. 6. Chronic administration of psychostimulants such as cocaine induces the accumulation of a transcription factor, . The induced Cdk. 5 increases DARPP- 3. Thr. 75 phosphorylation and therefore decreases D1 receptor/PKA signaling. The attenuation of D1 receptor/PKA signaling is considered as adaptive changes to cocaine addiction. The role of DARPP- 3. Thr. 75 is also demonstrated in stimulatory action of caffeine (Lindskog et al., 2. Caffeine, by antagonizing adenosine A2. A receptors in striatopallidal neurons, attenuates A2. A receptor/PKA signaling and PP- 2. A activity and subsequently increases DARPP- 3. Thr. 75 phosphorylation, which likely contribute to the stimulatory action of caffeine. Role of the CK2 Phosphorylation- Site at Ser. DARPP- 3. 2 and the CK1 Phosphorylation- Site at Ser. DARPP- 3. 2Phosphorylation of DARPP- 3. Ser. 97 (in mouse sequence; Ser. CK2 is reported to increase the efficacy of DARPP- 3. Thr. 34 phosphorylation by PKA (Girault et al., 1. In parallel, phosphorylation of DARPP- 3. Ser. 13. 0 (in mouse sequence; Ser. CK1 decreases the rate of dephosphorylation of Thr. Desdouits et al., 1. Thus, DARPP- 3. 2 phosphorylation by CK2 or CK1 results in the increase in the phosphorylation states of DARPP- 3. Thr. 34, suggesting the role of CK2 and CK1 to enhance D1 receptor/PKA/DARPP- 3. PP- 1 signaling cascade. However, an opposing action of CK2 to inhibit D1 receptor/PKA signaling is demonstrated (Rebholz et al., 2. CK2 directly interacts with Gs/olf, and negatively controls the functions of D1 receptors as well as A2. A receptors by enabling faster internalization. Recently, the phosphorylation state of DARPP- 3. Ser. 97 is found to be a key regulator of nuclear export of DARPP- 3. Stipanovich et al., 2. DARPP- 3. 2 has been thought as cytoplasmic protein because majority of DARPP- 3. Walaas and Greengard, 1. DARPP- 3. 2 was noticed in some nuclei of medium spiny neurons (Ouimet and Greengard, 1. Importantly, activation of D1 receptor/PKA signaling induces the nuclear accumulation of DARPP- 3. Stipanovich et al., 2. The phosphorylation of DARPP- 3. Ser. 97 by CK2 functions as nuclear export signal of DARPP- 3. Ser. 97 is highly phosphorylated under basal conditions (Girault et al., 1. DARPP- 3. 2 is located in the nucleus. When PKA is activated, Ser. PKA- activated PP- 2. A/B5. 6. The inhibition of PP- 1 by phospho- Thr. DARPP- 3. 2 promotes histone H3 phosphorylation and regulates the nuclear function via mechanisms of chromatin remodeling. These findings provide mechanisms for D1 receptor/PKA/DARPP- 3. Regulation of D1 Receptor/PKA/DARPP- 3. Signaling by Neurotransmitters. The D1 receptor/PKA/DARPP- 3. GABA, acetylcholine, adenosine, serotonin, norepinephrine, nitric oxide, and neuropeptides (opioids, cholecystokinin, and neurotensin), in addition to dopamine (for the review, see Svenningsson et al., 2. The release of dopamine is also regulated by neurotransmitters, therapeutic drugs, and drugs of abuse (Schmitz et al., 2. Sulzer, 2. 01. 1). We recently reported the role of glutamate (Nishi et al., 2. PGE2 (Kitaoka et al., 2. Tanda et al., 2. 00. Hara et al., 2. 01. D1 receptor/PKA/DARPP- 3. The role of DARPP- 3.
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