Exogenous Proline and Betaine-induced Upregulation of Glutathione Transferase and Glyoxalase I in Lentil ( Lens culinaris ) under Drought Stress

A G-quadruplex (G4) is a typical non-B DNA structure and involved in various DNA-templated events in eukaryotic genomes. PEG and PDS chemicals have been widely applied for promoting the folding of in vivo or in vitro G4s. However, how PEG and PDS preferentially affect a subset of G4 formation genome-wide is still largely unknown. We here conducted a BG4-based IP-seq in vitro under K⁺+PEG or K⁺+PDS conditions in the rice genome. We found that PEG-favored IP-G4s⁺ have distinct sequence features, distinct genomic distributions and distinct associations with TEGs, non-TEGs and subtypes of TEs compared to PDS-favored ones. Strikingly, PEG-specific IP-G4s⁺ are associated with euchromatin with less enrichment levels of DNA methylation but with more enriched active histone marks, while PDS-specific IP-G4s⁺ are associated with heterochromatin with higher enrichment levels of DNA methylation and repressive marks. Moreover, we found that genes with PEG-specific IP-G4s⁺ are more expressed than those with PDS-specific IP-G4s⁺, suggesting that PEG/PDS-specific IP-G4s⁺ alone or coordinating with epigenetic marks are involved in the regulation of the differential expression of related genes, therefore functioning in distinct biological processes. Thus, our study provides new insights into differential impacts of PEG and PDS on G4 formation, thereby advancing our understanding of G4 biology.

In Bangladesh, maize stands second place after rice; since it faces diverse natural calamities during its highest growing season (rabi/winter), particularly strong storm during the reproductive stage. Sometimes in some regions, this crop is completely damaged by natural disasters. Considering the burning issue, thirteen hybrids, including 10 previously selected short stature hybrids were evaluated against three local and standard checks: ‘BHM-9’, ‘981’ and ‘Sunshine’ in two consecutive years in seven locations of Bangladesh. Combined analysis over locations and seasons instigated that genotypes ‘Sunshine’, ‘981’ and ‘G10’ were the top-high yielders, while genotypes ‘G1’, ‘G2’, ‘BHM-9’ and ‘Sunshine’ were found the most stable. On the other hand, five genotypes such as ‘G3’, ‘G4’, ‘G6’, ‘G8’ and ‘G9’ had the below-average mean yield and the genotypes ‘G6’ and ‘G9’ were the most unstable. Among the seven environments, Jamalpur, Joydebpur and Dinajpur were most discriminating and Ishwardi was the least discriminating; whereas Joydebpur was more representative and Borishal was the least representative of other test environments. In the case of plant and ear height, most of the genotypes showed a lower value than all the checks, which was desirable. But among the top three high yielders, local cross-genotype, the ‘G10’ had the lowest and more stable value for both plant height and ear height. Therefore, considering the plant and ear height, grain yield, and yield stability, the genotype ‘G10’ has been recommended for release as commercial variety and has been released as new maize variety in Bangladesh with the local name of ‘BARI Hybrid Maize-16’ (BHM-16).

Glutathione S-transferease (GST) activities involved in antioxidant defense and methylglyoxal detoxification were investigated in the seedlings of a Bangladeshi maize variety, BARI hybrid maize-7, to understand the protecting mechanism under cold stress condition. The activities of glutathione S-transferase (GST) increased, while the activities of catalase (CAT) decreased with the duration of stress. The western blot analysis of the dominant GST revealed that it significantly accumulated during the stress period. The continual increase in H2O2 contents along with reduced redox state and activities suggested their roles in maintaining the glutathione homeostasis. The accumulation of GST with the content of H2O2 suggested its detoxification roles for organic hydroperoxides during chilling stress. Considering all, glutathione S-transferase (GST) enzymes showed protective role in maize from oxidative damages under Chilling condition.Res. Agric., Livest. Fish.2(1): 9-15, April 2015