Yazar "Ozturk, Neslihan Z." seçeneğine göre listele

Listeleniyor 1 - 2 / 2
  • Küçük Resim Yok
    Öğe
    Comparison of expression patterns of selected drought-responsive genes in barley (Hordeum vulgare L.) under shock-dehydration and slow drought treatments
    (SPRINGER, 2016) Gurel, Filiz; Ozturk, Neslihan Z.; Yoruk, Emre; Ucarli, Cuneyt; Poyraz, Nazaret
    Shock-like water stress using hydroponics and gradual water deficit in soil are the two widely used treatments to analyze transcriptional response of many crops to drought. In this study, we investigated the effects of shock drought (ShD) (0, 0.5, 1, 4, and 8 h) and slow drought (SDD) [soil water content (SWC) of 35 and 50 %] on the expression of well-known drought-responsive genes supplemented with physiological changes in barley. Two barley cultivars with contrasting leaf relative water content (RWC) and water loss rate (WLR) values were selected as Marti (MR; 60 % RWC and 0.046 gh(-1) g(-1) DW) and Erginel90 (ER; 38.3 % RWC and 0.350 gh(-1) g(-1) DW) under 38 % of SWC condition. According to the results, 0.5 h ShD was the critical time point for stress perception in leaves defined by the increase in WLR, ion leakage and H2O2 concentration. Expressions of antioxidant-related genes (Cu-Zn/SOD, HvCAT2, HvGST6, HvAPX) were rapidly induced in MR at 8 h shock, while only slightly upregulated in ER. We have also observed higher induction of expressions of HvBAS1, HvMT-2, HvABA7 and a photosynthesis-related gene HvLHCB during ShD compared to SDD. Contrarily, transcription factors (TFs), HvWRKY12 and HvDRF1 were expressed with lower values during shock-dehydration. Slow-drought treatments in both cultivars were characterized with high leaf RWCs and osmotic adjustment with low cell membrane damage, suggesting that barley maintains a basal tolerance to long-term water deficit. Our results confirmed that type of water stress treatment is crucial to measure gene expression, and a shock-like dehydration method should be the treatment of choice in evaluating barley plants with different physiological characteristics for water tolerance.
  • Küçük Resim Yok
    Öğe
    From Genetics to Functional Genomics: Improvement in Drought Signaling and Tolerance in Wheat
    (FRONTIERS MEDIA SA, 2015) Budak, Hikmet; Hussain, Babar; Khan, Zaeema; Ozturk, Neslihan Z.; Ullah, Naimat
    Drought being a yield limiting factor has become a major threat to international food security. It is a complex trait and drought tolerance response is carried out by various genes, transcription factors (TFs), microRNAs (miRNAs), hormones, proteins, co-factors, ions, and metabolites. This complexity has limited the development of wheat cultivars for drought tolerance by classical breeding. However, attempts have been made to fill the lost genetic diversity by crossing wheat with wild wheat relatives. In recent years, several molecular markers including single nucleotide polymorphisms (SN Ps) and quantitative trait loci (QTLs) associated with genes for drought signaling pathways have been reported. Screening of large wheat collections by marker assisted selection (MAS) and transformation of wheat with different genes/1-Es has improved drought signaling pathways and tolerance. Several miRNAs also provide drought tolerance to wheat by regulating various TFs/genes. Emergence of OMICS techniques including transcriptomics, proteomics, metabolomics, and ionomics has helped to identify and characterize the genes, proteins, metabolites, and ions involved in drought signaling pathways. Together, all these efforts helped in understanding the complex drought tolerance mechanism. Here, we have reviewed the advances in wide hybridization, MAS, QTL mapping, miRNAs, transgenic technique, genome editing system, and above mentioned functional genomics tools for identification and utility of signaling molecules for improvement in wheat drought tolerance.