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a b s t r a c tIn the phylogeny of plant polyamine oxidases (PAOs), clade III members from angiosperms, such as Arabidopsis thaliana PAO5 and Oryza sativa PAO1, prefer spermine and thermospermine as substrates and back-convert both of these substrates to spermidine in vitro. A clade III representative of lycophytes, SelPAO5 from Selaginella lepidophylla, also prefers spermine and thermospermine but instead back-converts these substrates to spermidine and norspermidine, respectively. This finding indicates that the clade III PAOs of lycophytes and angiosperms oxidize thermospermine at different carbon positions. We discuss the physiological significance of this difference.

A rice cDNA, OsDEP1, encoding a highly cysteine (Cys)-rich G protein γ subunit, was initially identified as it conferred cadmium (Cd) tolerance on yeast cells. Of the 426 aa constituting OsDEP1, 120 are Cys residues (28.2%), of which 88 are clustered in the C-terminal half region (aa 170–426). To evaluate the independent effects of these two regions, two truncated versions of the OsDEP1-expressing plasmids pOsDEP1(1–169) and pOsDEP1(170–426) were used to examine their effects on yeast Cd tolerance. Although OsDEP1(170–426) conferred a similar level of Cd tolerance as the intact OsDEP1, OsDEP1(1–169) provided no such tolerance, indicating that the tolerance effect is localized to the aa 170–426 C-terminal peptide region. The Cd responses of transgenic Arabidopsis plants constitutively expressing OsDEP1, OsDEP1(1–169) or OsDEP1(170–426), were similar to the observations in yeast cells, with OsDEP1 and OsDEP1(170–426) transgenic plants displaying Cd tolerance but OsDEP1(1–169) plants showing no such tolerance. In addition, a positive correlation between the transcript levels of OsDEP1 or OsDEP1(170–426) in the transgenics and the Cd content of these plants upon Cd application was observed. As several Arabidopsis loss-of-function heterotrimeric G protein β and γ subunit gene mutants did not show differences in their Cd sensitivity compared with wild-type plants, we propose that the Cys-rich region of OsDEP1 may function directly as a trap for Cd ions.

Force-responsive ordered carbonaceous frameworks (OCFs) are synthesized for the first time. Carbonization of Ni porphyrin monomers having eight polymerizable ethynyl groups yields OCFs with atomically dispersed divalent Ni species and...

Objectives To evaluate the efficacy of ultrasound (US) as a diagnostic tool for sarcopenia in patients with rheumatoid arthritis (RA). Methods Female RA patients aged >50 years and matched controls were cross-sectionally assessed. Sarcopenia was diagnosed based on the 2019-updated Asian Working Group for Sarcopenia definition. The cross-sectional area (CSA) and echo intensity (EI) of the biceps brachii, rectus femoris, and EI of the vastus lateralis were examined bilaterally. Correction for subcutaneous fat and calculation of the recorrected EI (rcEI) were performed. We performed logistic regression using both muscle rcEI and CSA with receiver operating curve analysis to evaluate the discriminative performance per muscle group. Results Seventy-eight consecutive RA patients and 15 age-and sex-matched controls were assessed. Sarcopenia was diagnosed in 34 RA patients (43.6%). The rcEI of examined muscles were significantly higher, whereas CSA were significantly lower in sarcopenic RA patients than in non-sarcopenic patients and matched controls. The combined discriminative performance of rcEI and CSA was superior to those of rcEI or CSA alone. Conclusions This study suggests the use of US for the diagnosis of sarcopenia in RA patients. The diagnostic performance increases when both echogenicity and CSA are considered together rather than individually.

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1921are reported in Table 3. Moreover, in both compounds, the Br atom has a short contact distance with an O atom of the substituted base [(I): Br...O(6) (-x, y-~, -z)= 3.285 (5) A; (II): Br...O(4) (x-1, y, z)= 2.993 (7),A.]. The pyrimidine moiety being non-planar due to the substitutions, no base stacking was observed in either compound.

Polyamine levels are controlled by biosynthesis, intra-and inter-cellular flux by the respective transporters, and catabolism. The catabolism is catalyzed by two groups of enzymes. One is copper-containing amine oxidases and the other is polyamine oxidases (PAOs). In Oryza sativa, seven PAO genes exist and they are termed as OsPAO1 to OsPAO7. However, their physiological function has not been elucidated yet. Here, we examined the expressional changes of seven OsPAO genes upon abiotic and oxidative stress, phytohormone, and exogenous polyamines application. The transcript of extracellular polyamine oxidase OsPAO2 and OsPAO6 are strongly induced upon wounding, drought, salinity, oxidative stress (H 2 O 2 ), and exogenous application of jasmonic acid, spermidine, spermine, thermospermine and negatively regulated upon indole acetic acid, isopentenyl adenine (iPT), gibberellic acid (GA), abscisic acid; OsPAO7 is to iPT, GA and all polyamines; OsPAO4 and OsPAO5 are mildly responsive to heat, cold, oxidative stress. These results suggest that polyamine oxidase encoding extracellular enzyme may play a pivotal role during exogenous stimulus to protect the plant cell.