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Phytohormones play critical roles in regulating plant responses to stress. Here, we investigated the effects of salt stress and stress recovery by applying jasmonate to the two different rice (Oryza sativa L.) cultivars Dongjinchalbyeo (DJC, salt-tolerant) and Dongjinbyeo (DJ, salt-sensitive). Salt stress remarkably decreased the root length of plants even at low NaCl concentration (20 mm). Salt stress led to a sharp increase in the concentrations of abscisic acid (ABA) in 20 and 40 mm NaCl, when compared with the control values. The concentrations of ABA in the salt-tolerant cultivar DJC plants progressively increased with increasing NaCl levels, whereas in the salt-sensitive cultivar DJ, they sharply decreased in all three parts of rice plants at 80 mm NaCl treatment. The decrease of jasmonic acid (JA) concentrations in salt-tolerant cultivar DJC was lesser than in the saltsensitive cultivar DJ plants in the shoot. Post-application in the stressed plants with 30 lm JA at 24 and 48 h after NaCl treatment, recovered salt inhibition on dry mass production more effectively than application of JA at 48 and 24 h before salt stress, and during salt stress simultaneously. The uptake of Na decreased especially in the salt-sensitive cultivar DJ plants, whereas there was an increase in Ca and Mg levels and slight increase of K by JA application. Leaf water potential, leaf photosynthetic rate, and maximum quantum yield of photosystem II (PSII) also remarkably recovered when 30 lm JA was applied 24 h after the salt stress compared with the 40 mm NaCl-treated plants. These results clearly indicate that post-application with exogenous JA can ameliorate salt-stressed rice seedlings, especially the salt-sensitive cultivar rather than the salt-tolerant cultivar. This may change the balance of other endogenous plant hormones.Key words: abscisic acid -ion uptake -jasmonic acid -leaf photosynthesis -leaf water potential -maximum quantum yield of PSII (Fv/Fm)

Here, we report efficient and stable indium phosphide (InP) based inverted red quantum dot light-emitting diodes (QLEDs) using a new high mobility and deep HOMO level hole transport layer (HTL) and an optimized sol−gel ZnMgO layer. A new hole transport material, DBTA, containing rigid dibenzothiophene and tertiary amine units has been designed with high hole mobility and a deep HOMO level to inject holes faster into the InP-QDs. Also, to decrease the electron transporting property of the ZnMgO NPs, a sol−gel ZnMgO layer with optimum magnesium content (17%), low-temperature annealing (180 °C), and a selfaging process is used on the transparent electrode. The high mobility DBTA and an optimized sol−gel Zn 0.83 Mg 0.17 O layer with the self-aging process are responsible for achieving good charge balance and suppressing nonradiative losses in InP-QLED. The fabricated QLED with DBTA and optimized sol− gel Zn 0.83 Mg 0.17 O exhibited an external quantum efficiency of 21.8%, current efficiency of 23.4 cd/A, and operating lifetime (LT 50 ) of 1095 h at 1000 cd/m 2 .

Obesity represents a major global public health problem that increases the risk for cardiovascular or metabolic disease. The pigs represent an exceptional biomedical model related to energy metabolism and obesity in humans. To pinpoint causal genetic factors for a common form of obesity, we conducted local genomic de novo sequencing, 18.2 Mb, of a porcine QTL region affecting fatness traits, and carried out SNP association studies for backfat thickness and intramuscular fat content in pigs. In order to relate the association studies in pigs to human obesity, we performed a targeted genome wide association study for subcutaneous fat thickness in a cohort population of 8,842 Korean individuals. These combined association studies in human and pig revealed a significant SNP located in a gene family with sequence similarity 73, member A (FAM73A) associated with subscapular skin-fold thickness in humans (rs4121165, GC-corrected p-value  = 0.0000175) and with backfat thickness in pigs (ASGA0029495, p-value  = 0.000031). Our combined association studies also suggest that eight neuronal genes are responsible for subcutaneous fat thickness: NEGR1, SLC44A5, PDE4B, LPHN2, ELTD1, ST6GALNAC3, ST6GALNAC5, and TTLL7. These results provide strong support for a major involvement of the CNS in the genetic predisposition to a common form of obesity.

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Isoflavones decrease blood pressure, improve lipid profiles, and restore vascular function. We hypothesized that isoflavone attenuates vascular contraction by inhibiting RhoA/Rho-kinase signaling pathway. Rat aortic rings were denuded of endothelium, mounted in organ baths, and contracted with 11,9 epoxymethano-prostaglandin F 2␣ (U46619), a thromboxane A2 analog, or KCl 30 min after the pretreatment with genistein (4Ј,5,7-trihydroxyisoflavone), daidzein (4Ј,7-dihydroxyisoflavone), or vehicle. We determined the phosphorylation level of the myosin light chain (MLC 20 ), myosin phosphatase-targeting subunit 1 (MYPT1), and protein kinase C-potentiated inhibitory protein for heterotrimeric myosin light-chain phosphatase of 17 kDa (CPI17) by means of the Western blot. We also measured the amount of GTP RhoA as a marker regarding RhoA activation. The cumulative additions of U46619 or KCl increased vascular tension in a concentration-dependent manner, which were inhibited by pretreatment with genistein or daidzein. Both U46619 (30 nM) and KCl (50 mM) increased MLC 20 phosphorylation levels, which were inhibited by genistein and daidzein. Furthermore, both genistein and daidzein decreased the amount of GTP RhoA activated by either U46619 or KCl. U46619 (30 nM) increased phosphorylation of the MYPT1 Thr855 and CPI17 Thr38 , which were also inhibited by genistein or daidzein. However, neither genistein nor daidzein inhibited phorbol 12,13-dibutyrate-induced vascular contraction and CPI17 phosphorylation. In conclusion, isoflavone attenuates vascular contraction, at least in part, through inhibition of the RhoA/Rho-kinase signaling pathway.

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Sesquiterpene cyclase, a branch point enzyme in the general isoprenoid pathway for the synthesis of phytoalexin capsidiol, was induced in detached leaves of Capsicum annuum (pepper) by UV treatment. The inducibility of cyclase enzyme activities paralleled the absolute amount of cyclase protein(s) of pepper immunodetected by monoclonal antibodies raised against tobacco sesquiterpene cyclase. A cDNA library was constructed with poly(A)+ RNA isolated from 24 h UV-challenged leaves of pepper. A cDNA clone for sesquiterpene cyclase in pepper was isolated by using a tobacco 5-epi aristolochene synthase gene as a heterologous probe. The predicted protein encoded by this cDNA was comprised of 559 amino acids and had a relative molecular mass of 65,095. The primary structural information from the cDNA clone revealed that it shared 77%, 72% and 49% identity with 5-epi aristolochene, vetispiradiene, and cadinene synthase, respectively. The enzymatic product catalyzed by the cDNA clone in bacteria was identified as 5-epi aristolochene, as judged by argentation TLC. RNA blot hybridization demonstrated the induction of an mRNA consistent with the induction of cyclase enzyme activity in UV-treated pepper.