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121.
Chitta Kasyapa Ting‐Lei Gu Lalitha Natarajan Roberto Polakiewicz John K. Cowell 《Proteomics》2009,9(16):3979-3988
The ZNF198‐fibroblast growth factor receptor‐1 (FGFR1) fusion kinase is a constitutively activated tyrosine kinase associated with a specific atypical myeloproliferative disease. The chimeric protein localizes to the cytoplasm, unlike the wild type FGFR1 receptor kinase, and presumably inappropriately phosphorylates specific targets as part of the oncogenic signaling cascade. Other than known targets of the FGFR1 kinase itself, few specific targets of ZNF198‐FGFR1 have been identified. Using a genetically engineered HEK 293 cell system, we have identified proteins that are specifically phosphorylated in the presence of the fusion kinase using anti‐phosphotyrosine immunoprecipitation and MS. Compared with 293 cells expressing exongenous wild type FGFR1, ZNF198‐FGFR1 is associated with phosphorylation of several proteins including SSBP2, ABL, FLJ14235, CALM and TRIM4 proteins. The specificity of the phosphorylation events in the SSBP2 and ABL proteins, which have previously been implicated in leukemogenesis, was further confirmed independently using immunoprecipitation with protein‐specific antibodies and Western blotting. The MS analysis also identified the phosphorylation events in the ZNF198 moiety in the chimeric protein that might be related to its function. These studies identify the intersection of several different leukemia‐related pathways in the development of this myeloproliferative disorder and provide new insights into the substrates of FGFR1 under defined conditions. 相似文献
122.
Arthur Mpimbaza Scott Filler Agaba Katureebe Linda Quick Daniel Chandramohan Sarah G. Staedke 《PloS one》2015,10(6)
To assess different methods for determining cause of death from verbal autopsy (VA) questionnaire data, the intra-rater reliability of Physician-Certified Verbal Autopsy (PCVA) and the accuracy of PCVA, expert-derived (non-hierarchical) and data-driven (hierarchal) algorithms were assessed for determining common causes of death in Ugandan children. A verbal autopsy validation study was conducted from 2008-2009 in three different sites in Uganda. The dataset included 104 neonatal deaths (0-27 days) and 615 childhood deaths (1-59 months) with the cause(s) of death classified by PCVA and physician review of hospital medical records (the ‘reference standard’). Of the original 719 questionnaires, 141 (20%) were selected for a second review by the same physicians; the repeat cause(s) of death were compared to the original,and agreement assessed using the Kappa statistic.Physician reviewers’ refined non-hierarchical algorithms for common causes of death from existing expert algorithms, from which, hierarchal algorithms were developed. The accuracy of PCVA, non-hierarchical, and hierarchical algorithms for determining cause(s) of death from all 719 VA questionnaires was determined using the reference standard. Overall, intra-rater repeatability was high (83% agreement, Kappa 0.79 [95% CI 0.76-0.82]). PCVA performed well, with high specificity for determining cause of neonatal (>67%), and childhood (>83%) deaths, resulting in fairly accurate cause-specific mortality fraction (CSMF) estimates. For most causes of death in children, non-hierarchical algorithms had higher sensitivity, but correspondingly lower specificity, than PCVA and hierarchical algorithms, resulting in inaccurate CSMF estimates. Hierarchical algorithms were specific for most causes of death, and CSMF estimates were comparable to the reference standard and PCVA. Inter-rater reliability of PCVA was high, and overall PCVA performed well. Hierarchical algorithms performed better than non-hierarchical algorithms due to higher specificity and more accurate CSMF estimates. Use of PCVA to determine cause of death from VA questionnaire data is reasonable while automated data-driven algorithms are improved. 相似文献
123.
Robert M. Tynebor Meng-Hsin Chen Swaminathan R. Natarajan Edward A. O’Neill James E. Thompson Catherine E. Fitzgerald Stephen J. O’Keefe James B. Doherty 《Bioorganic & medicinal chemistry letters》2010,20(9):2765-2769
The development and synthesis of potent p38α MAP kinase inhibitors containing a 2H-quinolizin-2-one platform is described. Evolution of the 2H-quinolizin-2-one series from an early lead to solving off target activity and pharmacokinetic issues is also discussed. 相似文献
124.
Substituting dietary linoleic acid with alpha-linolenic acid improves insulin sensitivity in sucrose fed rats 总被引:3,自引:0,他引:3
This study describes the effect of substituting dietary linoleic acid (18:2 n-6) with alpha-linolenic acid (18:3 n-3) on sucrose-induced insulin resistance (IR). Wistar NIN male weanling rats were fed casein based diet containing 22 energy percent (en%) fat with approximately 6, 9 and 7 en% saturated fatty acids (SFA), monounsaturated fatty acids (MUFA) and polyunsaturated fatty acids (PUFA) respectively for 3 months. IR was induced by replacing starch (ST) with sucrose (SU). Blends of groundnut, palmolein, and linseed oil in different proportions furnished the following levels of 18:3 n-3 (g/100 g diet) and 18:2 n-6/18:3 n-3 ratios respectively: ST-220 (0.014, 220), SU-220 (0.014, 220), SU-50 (0.06, 50), SU-10 (0.27, 10) and SU-2 (1.1, 2). The results showed IR in the sucrose fed group (SU-220) as evidenced by increase in fasting plasma insulin and area under the curve (AUC) of insulin in response to oral glucose load. In SU-220, the increase in adipocyte plasma membrane cholesterol/phospholipid ratio was associated with a decrease in fluidity, insulin stimulated glucose transport, antilipolytic effect of insulin and increase in basal and norepinephrine stimulated lipolysis in adipocytes. In SU-50, sucrose induced alterations in adipocyte lipolysis and antilipolysis were normalized. However, in SU-2, partial corrections in plasma insulin, AUC of insulin and adipocyte insulin stimulated glucose transport were observed. Further, plasma triglycerides and cholesterol decreased in SU-2. In diaphragm phospholipids, the observed dose dependent increase in long chain (LC) n-3 PUFA was associated with a decrease in LC-n-6 PUFA but insulin stimulated glucose transport increased only in SU-2. Thus, this study shows that the substitution of one-third of dietary 18:2 n-6 with 18:3 n-3 (SU-2) results in lowered blood lipid levels and increases peripheral insulin sensitivity, possibly due to the resulting high LCn-3 PUFA levels in target tissues of insulin action. These findings suggest a role for 18:3 n-3 in the prevention of insulin resistant states. The current recommendation to increase 18:3 n-3 intake for reducing cardiovascular risk may also be beneficial for preventing IR in humans. 相似文献
125.
CREB-1 is expressed in the bone marrow and in developing B cells. To determine the role of CREB-1 in developing B cells in the bone marrow, several lines of transgenic (Tg) mice overexpressing a dominant-negative Ser(119-ala) phosphomutant CREB-1 in the bone marrow were generated. Analysis of RNA and protein revealed expression of the transgene in the bone marrow. Flow cytometric analysis of bone marrow cells from Tg mice revealed approximately 70% increase in pre-B1 (CD43(+)B220(+)CD24(+(int))) and approximately 60% decreased pre-BII (CD43(+)B220(+)CD24(++(high))) cells, indicating a developmental block in pre-BI to pre-BII transition. Consistent with this, the Tg mice showed approximately 4-fold decrease in immature and mature B cells in the bone marrow. RT-PCR analysis of RNA from Tg mice revealed increased JunB and c-Jun in pre-BII cells associated with decreased S-phase entry. Adoptive transfer of bone marrow cells into RAG-2(-/-) mice resulted in reconstitution of non-Tg but not Tg bone marrow-derived CD43(+)B220(+)CD24(high) population that is normally absent in RAG-2(-/-) mice. In the periphery, the Tg mice exhibited decreased CD21(dim)CD23(high)IgM(+) follicular B cells in the spleen and increased B1a and B1b B cells in the peritoneum. While exhibiting normal Ab responses to T-independent Ags and primary response to the T-dependent Ag DNP-keyhole limpet hemocyanin, the Tg mice exhibited severely impaired secondary Ab responses. These studies provide the first evidence for a differential role for CRE-binding proteins in multiple stages of B cell development, functional maturation, and B1 and B2 B cells. 相似文献
126.
Mendes KN Nicorici D Cogdell D Tabus I Yli-Harja O Guerra R Hamilton SR Zhang W 《Journal of proteome research》2007,6(7):2753-2767
Multiple signal transduction pathways play a crucial role in cancer development, progression, and response to different therapies. An important issue is whether common signal transduction pathways are ubiquitously altered in all cancer types and some unique pathways are involved in different cancer types. Another important issue is whether and how transduction signaling molecules are heterogeneously expressed and activated in different cancer cells within and between cancer cell types. METHODS: To gain insight into these issues, we assembled a protein lysate array with 90 different cell lines of 12 different cell types. Each sample is diluted 2-fold six times, and samples from the dilution series were printed three times on the array. We then measured the expression levels and phosphorylation status of 52 different signaling proteins with specific antibodies and carried out statistical hierarchical clustering analysis. RESULTS: The most significant finding based on the cluster analysis was that the cell lines did not group based on tumor types, suggesting that the signaling pathways studied were commonly activated in most of the tumor types cultured in vitro. As expected, related proteins associated with specific signaling pathways clustered together, and analysis of the 30 most differentially expressed proteins revealed the PI3-K signaling pathway was upregulated in several different tumor types and the VEGF-angiogenesis pathway was downregulated in hematopoetic cancers. Another important observation, with clinical implications was that EGFR was the most heterogeneous among all the cell lines. We also observed signaling pathways unique to specific types of cancers such as the inverse relationship between p16ink and Rb, and the EGFR mediated pathway activation characteristic of pancreatic cancers. CONCLUSIONS: Using reverse phase lysate array analysis in this study, we were able to determine potential relationships and signaling pathways, both common and unique, to different types of cancer using cell lines in vitro. This data could be utilized for mining information related to an individual cancer of interest and combined with morphological and genomic profiles would help in creating a combination of expression markers and/or functional signaling maps for specific cancer diagnosis and therapy. 相似文献
127.
128.
Vishal Gupta Chitra Natarajan Kanika Kumar Radha Prasanna 《Journal of applied phycology》2011,23(1):73-81
A cyanobacterial strain (Anabaena laxa RPAN8) exhibiting fungicidal activity and β-1,3 and 1,4 endoglucanase activities was selected for identifying the gene(s)
involved. Functional analyses of the genomic library revealed that four clones (8, 64, 116, and 248) of RPAN8 exhibited fungicidal
activity and induced structural deformities in the cell wall of the growing mycelia of Pythium aphanidermatum. Higher expression of fungicidal and β-1,4 endoglucanase activities, along with low expression of β-1,3 endoglucanase activity,
was recorded in two E. coli clones (8 and 64). Clones 8 and 64 exhibited identical sequences while clones 116 and 248 were also similar. Bioinformatic
analyses were undertaken only for the two non-identical clones 8 and 116 which showed open reading frames (ORFs) of 348 (end 1) and 656 amino acid residues (end 2), respectively. The amino acid sequence analyses revealed that the end 1 encoding endoglucanases belonged to peptidase M20 family while end 2 showed significant similarities with several known genes. The putative promoters and ribosomal binding sites were identified
and amino acid exchanges were observed in both end 1 and 2. The presence of signal peptides of 24 and 20 amino acid residues respectively revealed the secretory nature of these
proteins. 相似文献
129.
Natarajan Nandhakumar Sundararajan Sathish Suresh C. P. Ramalingam Sathishkumar 《Plant Cell, Tissue and Organ Culture》2020,143(2):485-485
Plant Cell, Tissue and Organ Culture (PCTOC) - This article has been retracted. Please see the retraction notice for more detail: https://doi.org/10.1007/s11240-020-01912-4 相似文献
130.
Crustacean growth and development is characterized by periodic shedding (ecdysis) and replacement of the rigid exoskeleton. Secretions of the X-organ sinus gland complex control the cellular events that lead to growth and molting. Western blot and ELISA results showed a progressive increase in growth arrest-specific protein (Gas7) from early postmolt stage to a maximum at late postmolt stage. Phosphorylation of ERK2, a downstream signaling protein, was also identified in the subsequent stages. ERK2 phosphorylation resulted in the expression of molt-inhibiting hormone (MIH). Specific ERK inhibitors (PD98059 and UO126) exhibited the ability to reduce the molting duration of Fenneropenaeus indicus from 12-14 days to 7-8 days, suggesting that the ERK1/2 signaling pathway is responsible for the expression of MIH, which controls the molt cycle. We have identified the stage-specific expression of Gas7 (approximately 48 kDa) in the X-organ sinus gland complex of eyestalk which is involved in the downstream signaling of the ERK1/2 pathway regulating the expression of MIH during the molt cycle of the white shrimp, F. indicus. These are the first data showing an association between the Gas7 signal-transduction process and regulation of the molt cycle and provides an alternative molecular intervention mechanism to the traditional eyestalk ablation in crustaceans. 相似文献