Person: ÇELİK, ÖZGE
Loading...
Email Address
Birth Date
Research Projects
Organizational Units
Job Title
Prof.Dr.
Last Name
ÇELİK
First Name
ÖZGE
Name
50 results
Search Results
Now showing 1 - 10 of 50
Publication Metadata only Transcript profiling of salt tolerant tobacco mutants generated via mutation breeding(Elsevier, 2018-09) Ekşioğlu, Aybüke; Akdaş, Enes Yağız; ÇELİK, ÖZGE; 113987The main aim of the study is to identify the genes differentially, predominantly or specifically expressed in salt tolerant tobacco mutants, improved from Akhisar 97 and İzmir Özbaş varieties via mutation breeding, with respect to unstressed control plants. Seven tobacco mutants which have different salt tolerance capacities were evaluated by Gene Fishing analysis. Under stress conditions differentially expressed 100 reproducible bands were identified (74 of up-regulated and 20 of down-regulated while 6 were unknown). 75 of differentially expressed genes (DEGs) were successfully extracted from the gel and sequence analyses were performed. Functional annotation of the DEGs was performed against Blastn by interrogating their sequences. The 65 salt-regulated differentially expressed genes showed similarity with known genes, while 6 of DEGs didn't show any genetic similarities with known genes. DEGs were classified in eleven functional categories involving the abiotic stress response, biotic stress response, energy metabolism, cellular transport, catalitic activity, protein modification, amino acid metabolism and transcription factors. All the mutants were evaluated for their regulatory mechanisms against salt stress. The current data reveal that these six DEGs should be identified by next generation sequencing techniques and functional analysis should be design to understand the role of these six differentially expressed genes of tobacco mutants in further studies to improve new genetic resources.Publication Metadata only Selection and Molecular Profiling Of Salt Tolerant Tobacco Plants Obtained By Gamma Radiation(2010) ATAK, ÇİMEN; ÇELİK, ÖZGE; 113987; 6653Publication Metadata only Effects of Salinity Stress on Densities of Trichomes, Glandular Trichomes, and Stomata in Two Soybean Varieties(Springer, 233 Spring St, New York, Ny 10013 USA, 2010-09) Suludere, Zekiye; ATAK, ÇİMEN; ÇELİK, ÖZGE; 113987; 4019; 6653Publication Metadata only Effect of magnetic field on peroxidase activities of soybean tissue culture(DIAGNOSIS PRESS LTD, 67 DONDUKOV BLVD, 1504 SOFIA, BULGARIA, 2007-05) Olgun, Atok; Alikamanoğlu, Sema; Rzakoulieva, A.; ATAK, ÇİMEN; ÇELİK, ÖZGE; TR6653; TR141172In this study, the aim was to determine the effect of magnetic field on peroxidase activities of soybean tissue culture. Shoot tips were put into petri dishes and exposed to a magnetic field for a period of 2.2 and 19.8 s at a magnetic flux of 2.9-4.6 mT. The shoot and root formation rate, fresh weights, chlorophyll quantities, total RNA concentrations and peroxidase activities of regenerated shoots from control and treated shoot tips were determined. While the rate of shoot formation was 28.57% in the control group, this rate was increased to 94.33% and 78.18%, respectively, in the explants that were exposed to a magnetic field for a period of 2.2 and 19.8 s. While the percentage of root formation in controls was 4.76%, this rate increased to 47.17% and 54.54%, respectively, in those that were exposed to a magnetic field at the same periods. When the fresh weights were determined, we found that the fresh weights of plantlets regenerated from treated explants were increased relative to controls. Chlorophyll a, chlorophyll b and total chlorophyll contents increased 21%, 13% and 18%, respectively, relative to control groups at 2.2 s. Peroxidase activity significantly increased in all magnetic field treatments (p<0.05). The total RNA concentration of seedlings regenerated from treatment explants significantly increased relative to controls (p<0.05). The regeneration and plant growth of shoot tips exposed to a magnetic field with a 2.2 s period were positively affected by the MF and increased with respect to controls and the length of time exposed.Publication Metadata only Tauroursodeoxycholic acid and secondary damage after spinal cord injury in rats(CHURCHILL LIVINGSTONE, JOURNAL PRODUCTION DEPT, ROBERT STEVENSON HOUSE, 1-3 BAXTERS PLACE, LEITH WALK, EDINBURGH EH1 3AF, MIDLOTHIAN, SCOTLAND, 2008-06) Çolak, Ahmet; Kelten, Bilal; Sağmanlıgil, Ayhan; Akdemir, Osman; Karaoğlan, Alper; Şahan, Elife; Barut, Şeref; ÇELİK, ÖZGE; TR110561; TR110929; TR113987Greater clinical understanding of the pivotal role of apoptosis in spinal cord injury (SCI) has led to new and innovative apoptosisbased therapies for patients with an SCL Tauroursodeoxycholic acid (TUDCA) is a biliary acid with antiapoptotic properties. To our knowledge, this is the first study in the English language to evaluate the therapeutic efficacy of TUDCA in an experimental model of SCI. Thirty rats were randomized into three groups (sham-operated, trauma only, and trauma plus TUDCA treatment) of 10 each. In groups 2 and 3, spinal cord trauma was produced at the T8-T10 level via the Allen weight drop technique. Rats in group 3 were treated with TUDCA (200 mg/kg intraperitoneal) 1 min after trauma. The rats were killed either 24 h or 5 days after injury. The neuroprotective effect of TUDCA on injured spinal cord tissue and the effects of that agent on the recovery of hind-limb function were assessed. The efficacy of treatment was evaluated with histopathologic examination and terminal deoxynucleotidyl transferase-mediated dUTP-biotin nick-end labeling (TUNEL) analysis. Histopathologic characteristics were analyzed by comparison of hematoxylin-and-eosin stained specimens. Neurologic evaluations were performed 24 h, 3 days, and 5 days after trauma. Hind-limb function was assessed with the inclined plane technique of Rivlin and Tator and the modified version of Tarlov's grading scale. Twenty-four hours after injury, there was a significantly higher number of apoptotic cells in the lesioned spinal cord group than in the sham-operated control group. Treatment of the rats with TUDCA significantly reduced the number of apoptotic cells (4.52 +/- 0.30 vs. 2.31 +/- 0.24 in group 2) and the degree of tissue injury. Histopathologic examination showed that group 3 rats had better spinal cord architecture compared with group 2 rats. Five days after injury, the mean inclined plane angles in groups 1, 2, and 3 were 65.50 degrees +/- 2.09, 42.00 degrees +/- 2.74, and 53.50 degrees +/- 1.36. Motor grading of the rats revealed a similar trend. These differences were statistically significant (p < 0.05). The mechanism of neuroprotection in the treated rats, although not yet elucidated, may be related to the marked antiapoptotic properties of TUDCA. A therapeutic strategy using TUDCA may eventually lead to effective treatment of SCI without toxic effects in humans. (C) 2007 Elsevier Ltd. All rights reserved.Publication Metadata only Puccinellia distans - A potential plant to reveal boron toxicity and salt tolerance mechanisms(ELSEVIER, RADARWEG 29, 1043 NX AMSTERDAM, NETHERLANDS, 2019-11-15) Hakkı, E. E.; Pandey, A.; Khan, M. K.; Hamurcu, M.; Gezgin, S.; Atmaca, E.; İnanc, M.; Çakir, O.; Tarhan, C.; Sameeullah, M.; ÇELİK, ÖZGE; GÜMÜŞ, TAMERPublication Metadata only Differential regulation of antioxidative gene expressions in response to salt stress in rice(International Congress on Transcriptomics 27-29 Temmuz 2015, 2015) Candar, Bilgin; ATAK, ÇİMEN; ÇELİK, ÖZGE; 113987; 195745; 6653Rice (Oryza sativa L.) is one of the most important crops because it is a nutritional source of more than one-third of the world population. Soil salinity is one of the most important abiotic stress factors that affect plant growth and productivity adversely. Rice growth and yield is also affected by salinity and at the seedling stage although it is known to be susceptible to salinity. Reactive oxygen species are induced by salt stress and some responsive mechanisms are evolved against to the detrimental effects caused by salt stress. Salinity response is especially controlled by obtaining homeostasis between antioxidative mechanisms and accumulation of reactive oxygen species (ROS) produced as a result of oxidative stress caused by salinity. It is known that combined expression profiles of antioxidative system enzymes may provide increased tolerance capacity. Therefore, the expression profiles of antioxidative enzymes in two different rice cultivars which have different salt sensitivities at four different salt stress conditions were determined. Salinity responses of two different rice varieties were investigated at seedling stage. Four different salinity treatments were then applied using Yoshida solution containing 0, 30, 90, 150 and 210 mM NaCl to the nutrient solution for seven days. At the end of the seven days, the leaves were harvested and stored at -20oC for further experiments. The salt stress responsive gene specific primers were amplified by designed primers due to the 3?-UTR regions of each of the following genes by aligning all available related genes in the databases of NCBI and KOME: Mn-SOD, Cu/Zn-SOD, Fe-SOD, Cytosolic APX, Thylakoid-bound APX, stromal APX, Cytosolic GR and CatA. Mn-SOD was consisted with the trend of variation in SOD activities of rice varieties. The expression patternof CAT A gene was markedly decreased compared to control in both rice varieties. Str-APX gene expression was up-regulated during salt stress treatments in both rice varieties. Transcript levels of Cyt-APX and Thy-APX were up-regulated in accordance with increasing salt stress in Osmanc?k-97 variety. The expression pattern of gene encoding enzyme Cyt-GR1 showed a gradual up-regulation as a response to subjected increasing NaCl stress in Mevl�tbey variety while only after 90 mM treatment, an up-regulation was observed for Osmanc?k variety. These data indicated that the antioxidative responses of salt tolerant and salt sensitive rice varieties are differentially regulated.Publication Metadata only FTIR and EDXRF Investigations of Salt Tolerant Soybean Mutants(Elsevier Science Bv, Po Box 211, 1000 Ae Amsterdam, Netherlands, 2013-07-23) AKYÜZ, SEVİM; AKYÜZ, ZEKİ TANIL; ATAK, ÇİMEN; ÇELİK, ÖZGE; 10127; 111424; 113987; 6653Molecular structure and elemental composition of soybean (Glycine max L. Merr.) seeds of S04-05 (Ustun-1) variety together with its salt tolerant mutants were investigated by Fourier transform infrared (FTIR) and energy dispersive X-ray fluorescence (EDXRF) spectrometry. Salt tolerant soybean mutants were in vivo and in vitro selected from the M-2 generation of gamma irradiated S04-05 soybean variety. Examination of the secondary structure of proteins revealed the presence of some alterations in soybean mutants in comparison to those of the control groups. The difference IR spectra indicated that salt tolerant mutants (M-2) have less protein but more lipid contents. Chemometric treatment of the FTIR data was performed and principle component analysis (PCA) revealed clear difference between control group of seeds and mutants. EDXRF analysis showed that salt tolerant mutants considerably contained more chlorine, copper and zinc elements when compared to the control group, although most of the trace elements concentrations were not significantly altered. (C) 2013 Elsevier B.V. All rights reserved.Publication Metadata only Antioxidative defense system differences to drought stress of tomato cultivars(2014) AYAN, ALP; ATAK, ÇİMEN; ÇELİK, ÖZGE; 185510; 113987; 6653Publication Metadata only In Vitro and In Vivo Investigation of Salt Tolerance in Two Oriental Tobacco (Nicotiana tabacum L.) Species.(Springer, 233 Spring St, New York, Ny 10013 USA, 2009-09) ATAK, ÇİMEN; ÇELİK, ÖZGE; 113987; 6653