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Start Over Creator Zheng, J.

1. Anthocyanins function as a light attenuator to compensate for insufficient photoprotection mediated by nonphotochemical quenching in young leaves of Acmena acuminatissima in winter

Creator:
Zhu, H., Zhang, T.-J., Zheng, J., Huang, X.-D., Yu, Z.-C., Peng, C.-L., and Chow, W. S.
Format:
print, bez média, and svazek
Type:
model:article and TEXT
Subject:
stromy, pigmenty, roční období, ochrana před ultrafialovým zářením, trees, pigments, seasons, photoprotection, chlorophyll fluorescence, evergreen tree, gas exchange, 2, and 581
Language:
Multiple languages
Description:
Anthocyanins and nonphotochemical quenching (NPQ) are two important tools that provide photoprotection in plant leaves. In order to understand how plants use these tools for acclimation to changing seasonal conditions, we investigated pigments, antioxidative capacity, and photosynthesis in leaves of an evergreen tree (Acmena acuminatissima) in two contrasting seasons. Young leaves of A. acuminatissima appeared in distinct colors, being light green in summer and red in winter due to the presence of anthocyanins. In the winter young leaves, anthocyanins contributed less than 2% to the antioxidant pool. In the summer, young leaves had higher NPQ than that of mature leaves, but in the winter, they did not derive any NPQ-related advantage over mature leaves. These results suggest that the accumulation of anthocyanins in young leaves in the winter may compensate for the insufficient photoprotection afforded by NPQ and that anthocyanins function as a light attenuator to protect the photochemical apparatus against excess light., H. Zhu, T.-J. Zhang, J. Zheng, X.-D. Huang, Z.-C. Yu, C.-L. Peng, W. S. Chow., and Obsahuje bibliografické odkazy
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public

2. Extracellular hypotonicity induces disturbance of sodium current in rat ventricular myocytes

Creator:
Hu, L., Ma, P., Zhang, P., and Zheng, J.
Type:
article, články, model:article, and TEXT
Subject:
Fyziologie člověka a srovnávací fyziologie, elektrofyziologie, signální transdukce, electrophysiology, signal transduction, hypotonický roztok, ventrikulární myocyty, sodíkové kanály, celobuněčný záznam, hypotonic solution, ventricular myocytes, sodium channels, whole-cell recording, 14, and 612
Language:
English
Description:
Hypotonic solution alters ion channel activity, but little attention has been paid to voltage-dependent sodium channels. The aim of this study was to investigate the effects of hypotonic solution on transient sodium currents (INaT) and persistent sodium currents (INaP). We also explored whether the intracellular signal transduction systems participated in the hypotonic modifications of sodium currents. INaT and INaP were recorded by means of whole-cell patch-clamp technique in isolated rat ventricular myocytes. Our results revealed that hypotonic solution reduced INaT and simultaneously augmented INaP with the occurrence of interconversion between INaT and INaP. Hypotonic solution shifted steady-state inactivation to a more negative potential, prolonged the time of recovery from inactivation, and enhanced intermediate inactivation (IIM). Ruthenium red (RR, inhibitor of TRPV4), bisindolylmaleimide VI (BIM, inhibitor of PKC), Kn-93 (inhibitor of Ca/CaMKII) and BAPTA (Ca2+-chelator) inhibited the effects of hypotonic solution on INaT and INaP. Therefore we conclude that hypotonic solution inhibits INaT, enhances INaP and IIM with the effects being reversible. TRPV4 and intracellular Ca2+, PKC and Ca/CaMKII participate in the hypotonic modifications of sodium currents., L. Hu ... [et al.]., and Obsahuje seznam literatury
Rights:
http://creativecommons.org/licenses/by-nc-sa/4.0/ and policy:public