The fluctuation of proline content, and protein and mRNA levels of delta1-pyrroline-5-carboxylate synthetase (P5CS) and proline dehydrogenase (ProDH), both of which are involved in proline biosynthesis and degradation, in the shoots of Arabidopsis grown in light/dark cycles were demonstrated under salt-stressed and unstressed conditions. Proline content, as well as proteins and mRNAs of these enzymes, clearly oscillated in the light/dark cycles under the stressed and unstressed conditions. A reciprocal relationship between P5CS and ProDH was observed. Protein levels of P5CS and ProDH were well synchronized with their mRNA levels, although the fluctuation of protein levels was not as significant as that of their mRNA levels. Both mRNA and protein levels of the two enzymes as well as the proline content did not oscillate under the continuous light or the dark conditions. Thus, P5CS and ProDH gene expressions seemed to be involved in light irradiation. Moreover, relative water content (RWC) in the plants oscillated in the light/dark cycles. The fluctuations of proline content in shoot reversely responded to that of RWC. It is suggested that the expression of two genes responds sensitively to a subtle change of cellular water status, and accumulated proline keeps the osmotic balance between cells and the outer environment.
A car-borne survey for dose rate in air was carried out in March and April 2011 along an expressway passing northwest of the Fukushima Dai-ichi Nuclear Power Station which released radionuclides starting after the Great East Japan Earthquake on March 11, 2011, and in an area closer to the Fukushima NPS which is known to have been strongly affected. Dose rates along the expressway, i.e. relatively far from the power station were higher after than before March 11, in some places by several orders of magnitude, implying that there were some additional releases from Fukushima NPS. The maximum dose rate in air within the high level contamination area was 36 μGy h−1, and the estimated maximum cumulative external dose for evacuees who came from Namie Town to evacuation sites (e.g. Fukushima, Koriyama and Nihonmatsu Cities) was 68 mSv. The evacuation is justified from the viewpoint of radiation protection.
Mesenchymal stem cells/Transplantation/Embryonic stem cells/Radiation/Intestinal injury.The effective treatments of radiation-induced intestinal injury are currently unavailable. Developing new treatments for radiation-induced intestinal injury is thus important. The present study investigated whether transplantation of mesenchymal stem cells (MSCs) is able to prevent radiation-induced intestinal injury. Intestines of female nude mice (ICR nu/nu) were irradiated at a single dose of 30 Gy. Transplantation of male MSCs (C57BL/6) was then immediately performed into the walls of irradiated intestine by direct injection for the irradiation + MSCs group. Mice were weighed daily and survival was recorded for 13 days after irradiation. From 13 to 27 days after irradiation, intestines of mice were obtained in order to assay histological changes by staining with hematoxylin-eosin and Masson trichrome. Mean body weight of the irradiation + MSC group was significantly higher than that of the irradiation-only group from 8 days after irradiation. In addition, survival rates were significantly higher in the irradiation + MSC group than for the irradiation-only group from 5 days after irradiation. Histological observation revealed that intestines of irradiation + MSC-transplanted mice were thick in the submucosal and muscle layers, and had almost fully recovered from radiation-induced intestinal injury at day 27. Specifically, ulcerated areas in the intestines of the irradiation + MSC-transplanted mice were smaller by 13 days after irradiation and were fewer in numbers at 27 days when compared with the irradiation-only group. Our results suggest that transplanted MSCs may play an important role in preventing radiation-induced injury and may offer a novel method to treat radiation-induced intestinal injury.
Three kinds of 2H-labeled Bombyx mori silk fibroin samples (with [2,2-2H2]Gly, [3,3,3-2H3]Ala, or [2,3,5,6-2H4]Tyr) were obtained by oral administration of either the labeled amino acid or 2H2O to 5th instar larvae. The administration of 2H2O alone yielded a high degree of selective deuteration at the alanine methyl group, since the incorporation of 2H2O occurs between fumarate and malate in the tricarboxylic acid (TCA) cycle of the silk fibroin synthetic pathway. Uniaxially oriented silk fibers were prepared as samples for 2H-NMR spectroscopy. An analysis of the quadrupole echo line shape was carried out in order to determine the angle of the deuterium-labeled group relative to the fiber axis, i.e., of the Cα−2H bond vectors in glycine and of Cα−Cβ2H3 in alanine. With the fiber axis aligned parallel to the magnetic field, quadrupole splittings were obtained as 117.8 and 39.8 kHz for [2,2-2H2]Gly- and [3,3,3-2H3]Ala-labeled silk, respectively. These values are identical with those obtained from the 2H-NMR powder patterns of the unaligned samples, within experimental error. From the angular dependence of the quadrupole splittings, it was thus calculated that the Cα−2H bonds of glycine as well as the Cα−Cβ2H3 bond of alanine make an angle of approximately 90° relative to the fiber axis. These steric constraints were then used to evaluate the torsion angles, φ and ψ, for the glycine and alanine residues within the protein backbone. These data, determined independently by solid-state 2H NMR, thus verified and narrowed down the allowed region in the Ramachandran (φ, ψ) map obtained from previous solid-state 13C- and 15N-NMR studies.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.