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MYB transcription factors have various regulatory roles in response to biotic and abiotic stresses in plants. In this study we identified one MYB transcription factor gene OsJAMyb from rice landrace Heikezijing, which encodes a protein with 283 amino-acid residues belonging to R2R3-type MYB transcription factor family. The expression of OsJAMyb gene was detected in the root, stem, leaf, sheath, immature panicle and flowering panicle of rice, with highest expression in the leaf. After inoculation with the blast isolate Hoku1, the expression of OsJAMyb was more rapidly and strongly induced in the seedlings of blast-resistant Heikezijing compared with that in the blast-susceptible landrace Suyunuo. The OsJAMyb overexpressing transgenic lines (T 3 generation) in Suyunuo showed increased resistance to blast infection with less lesion number in inoculated leaves compared with non-transgenic control plants. The results indicate that OsJAMyb might be involved in the resistance to blast infection in rice. [ABSTRACT FROM AUTHOR]

Abstract: We present an optical sensor based on Solc filter to measure the transverse strain. The Solc filter is made of highly birefringent fibre by twisting its optical axes back and forth in equal sections. When a polarised light goes through the sensor, a periodic transmission response is obtained with a certain free spectra range (FSR) determined by the modal birefringence and the section length. The transverse strain can be measured by the shift of FSR from the transmitted response as the transverse stress changes the birefringence. More importantly we find that the measurement of transverse strain is free from the influence of temperature. We theoretically analyse the sensor model and simulate it by Jones Formalism. It is found that the sensitivity can achieve 7.14pm/με. The influence of section length, wavelength of light source, modal birefringence and number of sections on the sensitivity is also investigated. [Copyright &y& Elsevier]

It has been shown that the burst-phase (submillisecond) intermediate of barnase, if it exists, can be only marginally more stable than the fully unfolded state at pH 6.3 and 25 °C. In the study reported here, no stable burst-phase intermediate could be detected, even in the presence of stabilizing salt (0.4 M Na 2 SO 4 ). These results suggest that a burst-phase intermediate with even marginal stability does not exist. The absence of such an intermediate in turn suggests the need for re-examination of the rate-limiting transition state (RLTS) under native conditions, which was previously characterized by using a three-state model with a stable intermediate and protein engineering. Surprisingly, mutations throughout the structure of barnase do not significantly affect the folding rate, suggesting a lack of specific favorable interactions among the side-chains in the RLTS. This RLTS is clearly different from that previously characterized under denaturing conditions, indicating that changes take place in the RLTS under native and denaturing conditions. The occurrence of such changes is further supported by the observation that the unfolding rate constants of barnase and its mutants were divergent or convergent as a function of denaturant concentrations. Consistent with changes in the RLTS, a re-analysis of data from native-state hydrogen exchange studies has shown that the logarithm of the unfolding rate constant inflects down under low concentrations of denaturant. Here, we discuss in detail the question of whether changes in the RLTS involve a kinetically silent intermediate that occurs after the initial RLTS. [ABSTRACT FROM AUTHOR]

It has been shown that the burst-phase (submillisecond) intermediate of barnase, if it exists, can be only marginally more stable than the fully unfolded state at pH 6.3 and 25 °C. In the study reported here, no stable burst-phase intermediate could be detected, even in the presence of stabilizing salt (0.4 M Na2SO4). These results suggest that a burst-phase intermediate with even marginal stability does not exist. The absence of such an intermediate in turn suggests the need for re-examination of the rate-limiting transition state (RLTS) under native conditions, which was previously characterized by using a three-state model with a stable intermediate and protein engineering. Surprisingly, mutations throughout the structure of barnase do not significantly affect the folding rate, suggesting a lack of specific favorable interactions among the side-chains in the RLTS. This RLTS is clearly different from that previously characterized under denaturing conditions, indicating that changes take place in the RLTS under native and denaturing conditions. The occurrence of such changes is further supported by the observation that the unfolding rate constants of barnase and its mutants were divergent or convergent as a function of denaturant concentrations. Consistent with changes in the RLTS, a re-analysis of data from native-state hydrogen exchange studies has shown that the logarithm of the unfolding rate constant inflects down under low concentrations of denaturant. Here, we discuss in detail the question of whether changes in the RLTS involve a kinetically silent intermediate that occurs after the initial RLTS. [Copyright &y& Elsevier]

Abstract: Thiazolidinediones (TZDs) such as rosiglitazone are antidiabetic peroxisome proliferator-activated receptor γ (PPARγ) agonists. PPARγ agents improve diabetes by increasing insulin sensitivity and enhancing the differentiation of preadipocytes into adipocytes. The present study aimed to identify if 1-(4-chlorobenzoyl)-5-hydroxy-2-methyl-3-indoleacetitic acid (GY3), a newly synthesized indole compound, could enhance adipocytes differentiation and insulin sensitivity. The results showed that both GY3 and rosiglitazone significantly increased the lipid accumulating of 3T3-L1 adipocytes induced by isobutylmethylxanthine, dexamethasone and insulin mixture, but GY3 (not rosiglitazone) failed to increase the lipid accumulation when induced by insulin alone. In addition, GY3- or rosiglitaozne-induced protein expression of GLUT4 and adiponectin was determined by Western blot analysis. GY3 activated PPARα weakly but did not affect PPARγ, while rosiglitazone activated PPARγ significantly, suggesting different mechanisms between GY3 and rosiglitazone on adipocyte differentiation. Furthermore, both GY3 and rosiglitazone enhanced the adiponectin and insulin pathway proteins expression and adiponectin secretion in mature adipocytes, but only GY3 not rosiglitazone elevated gene expression of leptin and resistin. Both GY3 and rosiglitazone enhanced glucose consumption in HepG2 cells especially in the presence of insulin. In the in vivo study, GY3 decreased serum glucose and insulin in db/db mice, indicating the insulin sensitizing effect might contribute to its antidiabetic mechanism. Altogether, these results suggest that GY3 could improve insulin resistance and lower glucose level, GY3 and its derivatives might be developed as a substitution therapy for diseases with insulin resistance. [Copyright &y& Elsevier]