scholarly journals Effect of Freezing on Photosystem II and Assessment of Freezing Tolerance of Tea Cultivar

Plants ◽  
2019 ◽  
Vol 8 (10) ◽  
pp. 434 ◽  
Author(s):  
Yun-Long Shi ◽  
Zhuo-Yu Cai ◽  
Da Li ◽  
Jian-Liang Lu ◽  
Jian-Hui Ye ◽  
...  
Keyword(s):  
Photosystem Ii ◽  
Freezing Tolerance ◽  
De Novo ◽  
Photochemical Efficiency ◽  
D1 Protein ◽  
Freezing Stress ◽  
Control Group ◽  
Sensitivity Index ◽  
Instrumental Methods ◽  
Tea Cultivar

Freezing tolerant tea cultivars are urgently needed. The tea cultivars with highly freezing tolerance showed resistance to freezing stress induced photoinhibition. Freezing sensitivity index (H) of 47 tea clonal cultivars was investigated after severe freezing winter in 2016. To develop instrumental methods for freezing tolerance selection, the maximum photochemical efficiency of photosystem II (PSII) (Fv/Fm) and leaf color indicator a on the Hunter color scale were determined on control group (non-frozen) and frozen group (being frozen at −15 °C for 2 h and then stood at 20 °C for 5 h) of the cultivars. When the two indicators were expressed as the ratios (RFv/Fm and Ra) of frozen group to control group, linear regression of the freezing sensitivity index (H) upon the RFv/Fm and Ra produced significant relationship respectively, i.e., H = 60.31 − 50.09 RFv/Fm (p < 0.01) and H = 30.03 − 10.82 Ra (p < 0.01). Expression of gene psbA encoding D1 protein and gene psbD encoding D2 protein in PSII showed that the frezzing tolerant tea cultivars maintained a high expression level of psbA after freezing stress, which is considered to be beneficial to de novo synthesis of D1 protein and sustaining PSII activity. These findings can provide instrumental tools for assessing freezing tolerance of tea cultivars in tea breeding program.

scholarly journals Response of common buckwheat and Tartary buckwheat from different elevations to selenium treatment

Fagopyrum ◽  
2021 ◽  
Vol 38 (1) ◽  
pp. 15-23
Author(s):  
Aleksandra Golob ◽  
Neja Luzar ◽  
Mateja Germ
Keyword(s):  
Photosystem Ii ◽  
Photochemical Efficiency ◽  
Morphological Characteristics ◽  
Tartary Buckwheat ◽  
Control Group ◽  
Common Buckwheat ◽  
Biochemical Characteristics ◽  
Selenium Treatment ◽  
Uv Absorbing Compounds ◽  
Effective Photochemical Efficiency

Common buckwheat and Tartary buckwheat were grown in Slovenia outdoors at different elevations – 300 m, 600 m and 1180 m a.s.l. Both species were foliarly treated with selenium twice (in the vegetative phase and in the flowering phase). The effects of Se treatment and different growing locations on selected biochemical, physiological and anatomical traits were monitored. In Se treated common buckwheat, amount of chlorophylls was higher in plants from Ljubljana (the lowest elevation – 300 m a.s.l.) than in plants grown in Podbeže (600 m a.s.l.), whereas in control group, plants grown in Ljubljana contained more chlorophylls than plants from Javorje (the highest elevation – 1180 m a.s.l.). In both buckwheat species, Se alone did not affect amount of chlorophylls in any of location. In Se treated common buckwheat plants, the amount of UV absorbing compounds was the highest in plants, grown at the highest elevation. In common buckwheat, Se lowered the number of CaOx in plants, grown in Javorje. Conditions at different elevations, as well as treatments with Se, did not affect potential and effective photochemical efficiency of Photosystem II. Keywords: common buckwheat, Tartary buckwheat, elevation, selenium, morphological characteristics, biochemical characteristics

scholarly journals Progesterone increases photochemical efficiency of photosystem II in wheat under heat stress by facilitating D1 protein phosphorylation

2017 ◽  
Vol 55 (4) ◽  
pp. 664-670 ◽  
Author(s):  
R. L. Xue ◽  
S. Q. Wang ◽  
H. L. Xu ◽  
P. J. Zhang ◽  
H. Li ◽  
...  
Keyword(s):  
Heat Stress ◽  
Photosystem Ii ◽  
Protein Phosphorylation ◽  
Photochemical Efficiency ◽  
D1 Protein

scholarly journals Salicylic Acid Protects Photosystem II by Alleviating Photoinhibition in Arabidopsis thaliana under High Light

2020 ◽  
Vol 21 (4) ◽  
pp. 1229 ◽  
Author(s):  
Yang-Er Chen ◽  
Hao-Tian Mao ◽  
Nan Wu ◽  
Atta Mohi Ud Din ◽  
Ahsin Khan ◽  
...  
Keyword(s):  
Arabidopsis Thaliana ◽  
Salicylic Acid ◽  
Photosystem Ii ◽  
Excitation Energy ◽  
Light Exposure ◽  
Photochemical Efficiency ◽  
D1 Protein ◽  
High Light ◽  
Plant Responses ◽  
Protective Mechanisms

Salicylic acid (SA) is considered to play an important role in plant responses to environmental stresses. However, the detailed protective mechanisms in photosynthesis are still unclear. We therefore explored the protective roles of SA in photosystem II (PSII) in Arabidopsis thaliana under high light. The results demonstrated that 3 h of high light exposure resulted in a decline in photochemical efficiency and the dissipation of excess excitation energy. However, SA application significantly improved the photosynthetic capacity and the dissipation of excitation energy under high light. Western blot analysis revealed that SA application alleviated the decrease in the levels of D1 and D2 protein and increased the amount of Lhcb5 and PsbS protein under high light. Results from photoinhibition highlighted that SA application could accelerate the repair of D1 protein. Furthermore, the phosphorylated levels of D1 and D2 proteins were significantly increased under high light in the presence of SA. In addition, we found that SA application significantly alleviated the disassembly of PSII-LHCII super complexes and LHCII under high light for 3 h. Overall, our findings demonstrated that SA may efficiently alleviate photoinhibition and improve photoprotection by dissipating excess excitation energy, enhancing the phosphorylation of PSII reaction center proteins, and preventing the disassembly of PSII super complexes.

Post-illumination-related loss of photochemical efficiency of Photosystem II and degradation of the D1 protein are temperature-dependent

2005 ◽  
Vol 162 (11) ◽  
pp. 1246-1253 ◽  
Author(s):  
Munna Singh ◽  
Yasusi Yamamoto ◽  
Kimiyuki Satoh ◽  
Eva-Mari Aro ◽  
Eira Kanervo
Keyword(s):  
Photosystem Ii ◽  
Photochemical Efficiency ◽  
D1 Protein ◽  
Temperature Dependent

scholarly journals Initial Steps of Photosystem II de Novo Assembly and Preloading with Manganese Take Place in Biogenesis Centers in Synechocystis

2012 ◽  
Vol 24 (2) ◽  
pp. 660-675 ◽  
Author(s):  
Anna Stengel ◽  
Irene L. Gügel ◽  
Daniel Hilger ◽  
Birgit Rengstl ◽  
Heinrich Jung ◽  
...  
Keyword(s):  
Photosystem Ii ◽  
De Novo Assembly ◽  
De Novo

scholarly journals PIM2 and NF-κβ gene expression in a sample of AML and ALL Egyptian patients and its relevance to response to treatment

2021 ◽  
Vol 22 (1) ◽  
Author(s):  
Shymaa Kamal El Din Abed El Rahman ◽  
Sanaa Sayed Abd Elshafy ◽  
Mohamed Samra ◽  
Hala Mohammed Ali ◽  
Rabab Afifi Mohamed
Keyword(s):  
Overall Survival ◽  
Acute Leukemia ◽  
De Novo ◽  
Lymphoblastic Leukemia ◽  
Expression Level ◽  
Response To Treatment ◽  
Control Group ◽  
Poor Overall Survival ◽  
Healthy Control ◽  
Complete Blood Counts

Abstract Background The relation between PIM2 and the transcriptional factor NF κβ have been controversial in literature. The significance of PIM2 and NF-κβ genes expression on the incidence of acute leukemia (AML and ALL) and its relevance to the response rate was evaluated. Sixty de novo acute leukemia patients were stratified in 2 groups: 30 acute myeloid leukemia (AML) and 30 acute lymphoblastic leukemia (ALL) patients and compared to 30 sex- and age-matched controls. The expression level of PIM2 and NF κβ genes was measured using quantitative real-time polymerase chain reaction (QRT-PCR). The patients were followed with clinical examination and complete blood counts. Results The expression level of PIM2 gene was significantly higher in AML patients (P<0.001) compared to the control group. The mean expression level of NF κβ gene was significantly high in AML and ALL patients compared to the healthy control group (P=0.037 and P<0.001; respectively). The overall survival in AML patients was higher in NF κβ gene low expressers compared to high expressers (P=0.047). The number of AML patients who achieved complete remission was significantly higher in PIM2 gene low expressers in comparison to PIM2 gene high expressers (P=0.042). Conclusion PIM2 and NF κβ genes might have a role in the pathogenesis of acute leukemia, poor overall survival, and failure of response to induction therapy.

scholarly journals Preceding T-Cell-Mediated Rejection Is Associated with the Development of Chronic Active Antibody-Mediated Rejection by de Novo Donor-Specific Antibody

Nephron ◽  
2020 ◽  
pp. 1-5
Author(s):  
Takahiro Tsuji ◽  
Sari Iwasaki ◽  
Keishi Makita ◽  
Teppei Imamoto ◽  
Naomichi Ishidate ◽  
...  
Keyword(s):  
T Cell ◽  
Specific Antibody ◽  
De Novo ◽  
Control Group ◽  
Antibody Mediated Rejection ◽  
Peritubular Capillaries ◽  
The Mean ◽  
Microvascular Inflammation ◽  
Renal Allograft Loss ◽  
Allograft Loss

<b><i>Aim:</i></b> Chronic active antibody-mediated rejection (CAABMR) is an important cause of late-stage renal allograft loss. Early inflammatory events such as acute rejection and infection after transplantation are considered to be the risk factors of de novo donor-specific antibody (dnDSA) production. In this study, we investigated the relationship between pre­disposing T-cell-mediated rejection and dnDSA-positive CAABMR. <b><i>Methods:</i></b> We recruited 365 patients who underwent ABO-compatible renal transplantation at our hospital. Among them, 16 patients diagnosed as having dnDSA-positive CAABMR were designated as a CAABMR group, and 38 randomly selected patients were designated as a control group. All biopsies from 1 month after transplantation were included in the study. The presence or absence of borderline changes (BLCs), acute T-cell-mediated rejection (ATMR), microvascular inflammation (MVI), and C4d positive on peritubular capillaries (C4d-P) was examined. <b><i>Results:</i></b> In the CAABMR group, BLC/ATMR was found in 12 cases (75%), and the mean duration until appearance of BLC/ATMR was 282.7 ± 328.7 days. C4d-P was found in 11 cases (68.8%), and the mean duration until its appearance was 1,432 ± 1,307 days. MVI was found in all cases, and the mean duration until its appearance was 1,333 ± 1,126 days. The mean duration until diagnosis of CAABMR was 2,268 ± 1,191 days. In the control group, BLC/ATMR was found in 13 cases (34.2%), and the mean duration until the appearance of BLC/ATMR was 173.1 ± 170.4 days. C4d-P was found in 2 cases (5.3%), and the durations until its appearance were 748 and 1,881 days. No cases of MVI were found in the control group. The frequency of BLC/ATMR was significantly higher in the CAABMR group (<i>p</i> &#x3c; 0.01). <b><i>Conclusion:</i></b> Preceding BLC/ATMR is associated with the development of CAABMR with dnDSA.

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