PMC:3585731 / 10105-16461 JSON TXT

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testone

2_test

{"project":"2_test","denotations":[{"id":"23469174-19556857-90505428","span":{"begin":451,"end":453},"obj":"19556857"},{"id":"23469174-17560373-90505429","span":{"begin":810,"end":812},"obj":"17560373"},{"id":"23469174-15131264-90505430","span":{"begin":816,"end":818},"obj":"15131264"},{"id":"23469174-15131264-90505431","span":{"begin":938,"end":940},"obj":"15131264"},{"id":"23469174-20571069-90505432","span":{"begin":1792,"end":1794},"obj":"20571069"},{"id":"23469174-20489726-90505433","span":{"begin":1819,"end":1821},"obj":"20489726"}],"text":"RIP1 Kinase-dependent Activation of Akt Contributes to Necroptosis\nGiven our observation that growth factors are important for zVAD.fmk induced death, we examined the contribution of several pathways, including MAPK pathways and Akt, which are known to be activated following growth factor receptor activation (Fig. 2A). Inhibition of Akt (Akt inhibitor VIII) strongly protected the cells from growth factor-sensitive necroptosis induced by zVAD.fmk [16] as well as cell death triggered by bFGF or IGF-1/zVAD.fmk under serum free conditions (Fig. 2B). Inhibition of Akt also protected the cells from growth-factor insensitive death by caused by TNFα (Fig. 2A). Consistent with previous reports, the JNK inhibitor SP600125 protected the cells from both zVAD.fmk and TNFα induced death (Fig. 2A,B and Fig. S2A) [12], [14]. In contrast, inhibition of two other MAPKs, p38 and ERK, previously reported not to be activated during necroptosis [14], did not protect from either zVAD.fmk or TNFα induced death (Fig. 2A).\n10.1371/journal.pone.0056576.g002 Figure 2 Akt contributes to necroptosis induced by zVAD.fmk and TNFα.\n(A,B) Necroptosis was induced by zVAD.fmk or TNFα (full serum, A) or growth factors/zVAD.fmk (serum free, B) in the presence of inhibitors of Akt (Akt inhibitor VIII), JNK (SP600125), p38 (PD169316), and Erk (UO126). Cell viability was determined after 24 hrs. (C) L929 cells transfected with Akt1, Akt2, and Akt3 siRNAs for 72 hrs were treated with zVAD.fmk or TNFα for 9 hrs. Cell viability and Akt expression levels were determined after 24 hrs. In all graphs, average±SD was plotted. Next, we used two approaches to further validate the role of Akt in necroptotic cell death. First, two additional Akt inhibitors, a highly specific, allosteric kinase inhibitor MK-2206 [25] and triciribine (TCN) [26], which blocks membrane translocation of Akt, both attenuated cell death (Fig. S2B). Secondly, simultaneous knockdown of Akt isoforms Akt1 and Akt2 using siRNAs protected cells from necroptosis induced by both zVAD.fmk and TNFα (Fig. 2C). No expression of Akt3 was seen in L929 cells (Fig. S2C) and, consistently, Akt3 siRNA had no additional effect on necroptosis. Our results confirmed that Akt plays a key role in necroptosis induced by multiple stimuli in L929 cells.\nTo understand the activation of Akt and JNK under necroptotic conditions, we examined the changes in Akt and JNK phosphorylation at 9 hrs post zVAD.fmk and TNFα stimulation. This time point was chosen because it reflects the early stage of cell death in our system (Fig. S3A, B). Following stimulation with either zVAD.fmk or TNFα we observed a robust increase in Akt phosphorylation at a known major activation site, Thr308 (Fig. 3A). Interestingly, we did not observe concomitant phosphorylation changes in the second major activation site of Akt, Ser473. We also observed an increase in the phosphorylation of both the p46 and p54 isoforms of JNK and its major substrate c-Jun (Fig. 3A). These data indicate that both Akt and JNK are activated under necroptotic conditions.\n10.1371/journal.pone.0056576.g003 Figure 3 RIP1 kinase-dependent phosphorylation of Akt and JNK during necroptosis.\n(A) L929 cells were treated with zVAD.fmk or TNFα for 9 hr, followed by western blotting with indicated antibodies. (B,C) L929 cells were treated with zVAD.fmk (B) or bFGF/zVAD.fmk (serum free conditions, C) and samples were collected at the indicated time points for western blot. (D) Nec-1 was added to the cells stimulated with bFGF or bFGF/zVAD (serum free conditions) for 15 min or 9 hr followed by western blot with the indicated antibodies. The RIP1 kinase inhibitor, Nec-1, completely prevented the increase in Thr308 Akt phosphorylation, while Nec-1i did not (Fig. 3A, Fig. S1D). Similarly, Nec-1 prevented the induction of JNK phosphorylation in response to zVAD.fmk and substantially reduced this change after TNFα addition. We observed some changes in total protein levels of JNK and c-Jun following necroptotic stimulation. Some of these changes, e.g. zVAD.fmk-induced increase in c-Jun, were also attenuated by Nec-1. Importantly, Nec-1 did not alter the basal phosphorylation levels of either Akt or JNK (Fig. 3A). This established that Akt Thr308 and JNK phosphorylation during necroptosis is RIP1 dependent.\nInterestingly, we discovered that the phosphorylation of Akt Thr308, JNK and Jun are late events following zVAD.fmk stimulation (Fig. 3B) that coincide with the onset of necroptosis at 6 hr post-stimulation (Fig. S3A). To better understand the contributions of growth factors and RIP1 kinase to necroptotic regulation of Akt, we next analyzed the time course of these phosphorylation changes under serum free conditions. We found that the addition of bFGF alone or in combination with zVAD.fmk led to a substantial rapid and transient increase in both Thr308 and Ser473 phosphorylation of Akt as well as JNK and c-Jun at 15 minutes, reflecting the expected response to growth factor stimulation (Fig. 3C). Significantly, the combination of bFGF/zVAD.fmk, but not bFGF alone, also caused a robust, second, delayed increase in the phosphorylation of Thr308, but not Ser473, of Akt as well as a delayed increase in the phosphorylation of JNK and Jun. Furthermore, Nec-1 had no significant effect on the early increase in both Akt and JNK/c-Jun phosphorylation triggered by both bFGF and bFGF/zVAD, while Nec-1, but not its inactive analog Nec-1i (Fig. S1E), efficiently blocked the bFGF/zVAD increase at 6–9 hr (Fig. 3D), suggesting that only the delayed activation of Akt and JNK is specific for necroptosis and dependent on RIP1 kinase activity. Similarly, IGF/zVAD, which also promoted cell death under serum free conditions, produced a delayed increase in Thr308 phosphorylation on Akt, while IGF alone caused solely an early, transient increase in phosphorylation (Fig. S3C). We confirmed the kinetics of the Akt Thr308 and Ser473 phosphorylation changes using a quantitative ELISA assay, which also showed a robust delayed necroptosis-specific RIP1-dependent increase in Akt Thr308 phosphorylation (Fig. S3D, E). Taken together, these results indicate that the observed delayed increases in Akt and JNK phosphorylation, preceding the onset of cell death, represent specific consequences of necroptotic signaling downstream from RIP1 kinase."}

pmc-enju-pas

bionlp-st-ge-2016-test-proteins

bionlp-st-ge-2016-uniprot

UBERON-AE

{"project":"UBERON-AE","denotations":[{"id":"T28944","span":{"begin":1212,"end":1217},"obj":"http://purl.obolibrary.org/obo/UBERON_0001977"},{"id":"T28943","span":{"begin":1174,"end":1179},"obj":"http://purl.obolibrary.org/obo/UBERON_0001977"},{"id":"T29401","span":{"begin":3538,"end":3543},"obj":"http://purl.obolibrary.org/obo/UBERON_0001977"},{"id":"T29400","span":{"begin":3370,"end":3375},"obj":"http://purl.obolibrary.org/obo/UBERON_0001977"},{"id":"T5279","span":{"begin":5716,"end":5721},"obj":"http://purl.obolibrary.org/obo/UBERON_0001977"},{"id":"T5278","span":{"begin":4711,"end":4716},"obj":"http://purl.obolibrary.org/obo/UBERON_0001977"},{"id":"T5277","span":{"begin":519,"end":524},"obj":"http://purl.obolibrary.org/obo/UBERON_0001977"}],"text":"RIP1 Kinase-dependent Activation of Akt Contributes to Necroptosis\nGiven our observation that growth factors are important for zVAD.fmk induced death, we examined the contribution of several pathways, including MAPK pathways and Akt, which are known to be activated following growth factor receptor activation (Fig. 2A). Inhibition of Akt (Akt inhibitor VIII) strongly protected the cells from growth factor-sensitive necroptosis induced by zVAD.fmk [16] as well as cell death triggered by bFGF or IGF-1/zVAD.fmk under serum free conditions (Fig. 2B). Inhibition of Akt also protected the cells from growth-factor insensitive death by caused by TNFα (Fig. 2A). Consistent with previous reports, the JNK inhibitor SP600125 protected the cells from both zVAD.fmk and TNFα induced death (Fig. 2A,B and Fig. S2A) [12], [14]. In contrast, inhibition of two other MAPKs, p38 and ERK, previously reported not to be activated during necroptosis [14], did not protect from either zVAD.fmk or TNFα induced death (Fig. 2A).\n10.1371/journal.pone.0056576.g002 Figure 2 Akt contributes to necroptosis induced by zVAD.fmk and TNFα.\n(A,B) Necroptosis was induced by zVAD.fmk or TNFα (full serum, A) or growth factors/zVAD.fmk (serum free, B) in the presence of inhibitors of Akt (Akt inhibitor VIII), JNK (SP600125), p38 (PD169316), and Erk (UO126). Cell viability was determined after 24 hrs. (C) L929 cells transfected with Akt1, Akt2, and Akt3 siRNAs for 72 hrs were treated with zVAD.fmk or TNFα for 9 hrs. Cell viability and Akt expression levels were determined after 24 hrs. In all graphs, average±SD was plotted. Next, we used two approaches to further validate the role of Akt in necroptotic cell death. First, two additional Akt inhibitors, a highly specific, allosteric kinase inhibitor MK-2206 [25] and triciribine (TCN) [26], which blocks membrane translocation of Akt, both attenuated cell death (Fig. S2B). Secondly, simultaneous knockdown of Akt isoforms Akt1 and Akt2 using siRNAs protected cells from necroptosis induced by both zVAD.fmk and TNFα (Fig. 2C). No expression of Akt3 was seen in L929 cells (Fig. S2C) and, consistently, Akt3 siRNA had no additional effect on necroptosis. Our results confirmed that Akt plays a key role in necroptosis induced by multiple stimuli in L929 cells.\nTo understand the activation of Akt and JNK under necroptotic conditions, we examined the changes in Akt and JNK phosphorylation at 9 hrs post zVAD.fmk and TNFα stimulation. This time point was chosen because it reflects the early stage of cell death in our system (Fig. S3A, B). Following stimulation with either zVAD.fmk or TNFα we observed a robust increase in Akt phosphorylation at a known major activation site, Thr308 (Fig. 3A). Interestingly, we did not observe concomitant phosphorylation changes in the second major activation site of Akt, Ser473. We also observed an increase in the phosphorylation of both the p46 and p54 isoforms of JNK and its major substrate c-Jun (Fig. 3A). These data indicate that both Akt and JNK are activated under necroptotic conditions.\n10.1371/journal.pone.0056576.g003 Figure 3 RIP1 kinase-dependent phosphorylation of Akt and JNK during necroptosis.\n(A) L929 cells were treated with zVAD.fmk or TNFα for 9 hr, followed by western blotting with indicated antibodies. (B,C) L929 cells were treated with zVAD.fmk (B) or bFGF/zVAD.fmk (serum free conditions, C) and samples were collected at the indicated time points for western blot. (D) Nec-1 was added to the cells stimulated with bFGF or bFGF/zVAD (serum free conditions) for 15 min or 9 hr followed by western blot with the indicated antibodies. The RIP1 kinase inhibitor, Nec-1, completely prevented the increase in Thr308 Akt phosphorylation, while Nec-1i did not (Fig. 3A, Fig. S1D). Similarly, Nec-1 prevented the induction of JNK phosphorylation in response to zVAD.fmk and substantially reduced this change after TNFα addition. We observed some changes in total protein levels of JNK and c-Jun following necroptotic stimulation. Some of these changes, e.g. zVAD.fmk-induced increase in c-Jun, were also attenuated by Nec-1. Importantly, Nec-1 did not alter the basal phosphorylation levels of either Akt or JNK (Fig. 3A). This established that Akt Thr308 and JNK phosphorylation during necroptosis is RIP1 dependent.\nInterestingly, we discovered that the phosphorylation of Akt Thr308, JNK and Jun are late events following zVAD.fmk stimulation (Fig. 3B) that coincide with the onset of necroptosis at 6 hr post-stimulation (Fig. S3A). To better understand the contributions of growth factors and RIP1 kinase to necroptotic regulation of Akt, we next analyzed the time course of these phosphorylation changes under serum free conditions. We found that the addition of bFGF alone or in combination with zVAD.fmk led to a substantial rapid and transient increase in both Thr308 and Ser473 phosphorylation of Akt as well as JNK and c-Jun at 15 minutes, reflecting the expected response to growth factor stimulation (Fig. 3C). Significantly, the combination of bFGF/zVAD.fmk, but not bFGF alone, also caused a robust, second, delayed increase in the phosphorylation of Thr308, but not Ser473, of Akt as well as a delayed increase in the phosphorylation of JNK and Jun. Furthermore, Nec-1 had no significant effect on the early increase in both Akt and JNK/c-Jun phosphorylation triggered by both bFGF and bFGF/zVAD, while Nec-1, but not its inactive analog Nec-1i (Fig. S1E), efficiently blocked the bFGF/zVAD increase at 6–9 hr (Fig. 3D), suggesting that only the delayed activation of Akt and JNK is specific for necroptosis and dependent on RIP1 kinase activity. Similarly, IGF/zVAD, which also promoted cell death under serum free conditions, produced a delayed increase in Thr308 phosphorylation on Akt, while IGF alone caused solely an early, transient increase in phosphorylation (Fig. S3C). We confirmed the kinetics of the Akt Thr308 and Ser473 phosphorylation changes using a quantitative ELISA assay, which also showed a robust delayed necroptosis-specific RIP1-dependent increase in Akt Thr308 phosphorylation (Fig. S3D, E). Taken together, these results indicate that the observed delayed increases in Akt and JNK phosphorylation, preceding the onset of cell death, represent specific consequences of necroptotic signaling downstream from RIP1 kinase."}

GO-BP

GO-MF

GO-CC

sentences

simple1

BioNLP16_DUT

BioNLP16_Messiy

DLUT931

bionlp-st-ge-2016-test-ihmc

bionlp-st-ge-2016-spacy-parsed

bionlp-st-ge-2016-test-tees

test3

PMC:3585731 / 10105-16461 JSONTXT

Annnotations TAB JSON ListView MergeView

PMC:3585731 / 10105-16461 JSON TXT