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Purpose: The protein phosphatase-2A (PP-2A) is one of the most important serine/threonine phosphatases in eukaryotes. The holoenzyme of PP-2A consists of three subunits: a scaffold A subunit, a catalytic C subunit and a regulatory B subunit. While both A and C subunits are coded by two different genes, the B subunits exist in 26 or more isoforms which are encoded by at least 15 different genes. Previous studies have shown that besides regulating specific PP-2A activity, various B subunits may have other functions. To explore the possible roles of the regulatory subunits of PP-2A in vertebrate development, we have cloned the gene encoding goldfish striatin, a member of the B’” family regulatory subunits for PP-2A, and determined their tissue-specific and temporal expression patterns. Methods: The cDNA cloning was conducted with RT-PCR-based RACE. The mRNA expression levels for the goldfish striatin were analyzed with RT-PCR. The expression levels of the striatin protein from goldfish were determined with Western blot analysis. The semi-quantitation of the mRNA and protein expression levels was conducted with the software of U-scanning. Results: Our study revealed that the full length cDNA for striatin consists of 2965 bp coding for a deduced protein of 769 amino acids, which bears a very high level of amino acid sequence identity with the homolog protein from other species. The striatin mRNA is highly expressed in the kidney, to a less degree in brain, fin, muscle, liver, ovary and gill, and the lowest in testis and heart. Similar pattern of protein expression is detected in the above 9 tissues. During the development of goldfish, the striatin mRNA maintains a relatively high level at the 2-cell, multiple cell and blastula stages. Then, it drops down substantially at gastrula stage and fluctuates around this level in the next 8 different stages. At the protein level, the striatin maintained higher level from 2-cell to gastrula stages, then decreased at neurula and optic vesicle stages, and gradually increased again to peak at eye pigmentation stage, then slightly decreased in the next few stages of development. Conclusions: Our results suggest that the striatin may play an important role in regulating goldfish development and adult tissue homeostasis. While the former function may or may not occur through PP- 2A functions, the later function appears to occur via PP-2A activity.

Many nitrate pollution cases exceed the threshold as recommended by the World Health Organization (50mg NO3/L) and by the USA (10mg N/L) for drinking water. In-situ denitrification was regarded as a good method to decrease nitrate contamination but is restricted by carbon absent in groundwater. Considering the disadvantages of known carbon sources, this paper provided slow-release organic carbon-source (SOC) technique to solve the problem and the results showed that SOC materials showed good performance during simulated groundwater denitrification. Structure analysis suggested that hydroxy chemical bond existed between PVA and starch in SOC and surface configuration changed with materials dissolving into water. After seven days of domestication, with 40–50 mg/L initial NO3-N, denitrification efficiency increased from 806% to 90.7% and the real COD consumption per N-NO3 reduction was 1.82–3.73 with 2.79 as average. Denitrification process followed the law of zero order kinetics and the parameter of denitrification dynamics, K, was from 0.1366 to 0.1873. It was suggested that SOC was a potential carbon source material (electron donor) suitable for in-situ groundwater denitrification. [ABSTRACT FROM AUTHOR]

The electronic stabilization effect of the substituents on the nitrosyl-containing molecules has been studied by computing the electronic energy change (ΔE) in the isodesmic reactions, R−NO + H2 → H−NO + RH, at the B3LYP/6-311+G(d,p) level of theory. A total of 15 substituent groups (R) which span a wide range of σ and π donating/withdrawing strength have been included. Studies were extended to three isovalent analogues, namely, the NS-, PO-, and PS-containing molecules, with the same group of substituents. Computational results show that σ-withdrawing groups strongly destabilize the NS molecules, whereas in striking contrast, they substantially stabilize the PO molecules. The σ effect is much less pronounced in either the NO- or the PS-containing series. The π effect, however, is more unidirectional. Specifically, the π-donating groups contribute positively to the molecular stability in all four isovalent analogues. A semiquantitative analysis, which is based on the frontier molecular orbital theory, is presented. The vastly different responses of the isovalent groups toward the various substituents in their thermal stabilities, as well as their structures, are also discussed.

The final biological effect of auxin depends both on free auxin levels and on auxin perception capacity.RolBtransformedBeta vulgarisL. hairy roots provide a system for studying both factors. Highly purified plasma membrane fractions were prepared with aqueous two-phase partitioning. Individual hairy root clones were assessed for the binding activities of plasma membrane-bound auxin binding proteins and for their free intracellular indole-3-acetic acid levels. The presence of a high affinity auxin binding protein with a dissociation constant of 9.07 x 10−7M was detected in the plasma membrane fractions isolated from non-transformed seedling roots and the six clones ofrolBtransformed hairy roots. However, the levels of specific IAA binding considerably varied among different hairy root clones and between transformed and non-transformed roots. The levels of the detectable polypeptide in immunoblotting with an antibody against maize 22-kD auxin binding protein subunit were in good agreement to the levels that were detected in auxin binding assays. Differences in the indole-3-acetic acid levels were found between transformed and non-transformed roots and also between different transformed hairy root clones. A negative correlation was observed between free intracellular IAA levels and its specific binding to the plasma membrane-bound auxin binding proteins. A latency study indicated that the binding site for auxin may be located on the exterior face of the plasma membrane

Genomic in situ hybridization (GISH) offers a convenient and effective method for cytological detection, but can not determine the identity of the chromosomes involved. We integrated C-banding with GISH to identify Haynaldia villosa chromosomes in a wheat background. All chromosomes of H. villosa showed C-bands, either in telomeric regions or in both telomeric and centromeric regions, which allowed unequivocal identification of each H. villosa chromosome. The seven pairs of H. villosa chromosomes were differentiated as 1–7 according to their characteristic C-bands. Using a sequential C-banding and GISH technique, we have analyzed somatic cells of F3 plants from the amphiploid Triticum aestivum-H. villosa x ‘Yangmai 158’ hybrids. Three plants (94009/5-4,94009/5-8 and 94009/5-9) were shown to contain H. villosa chromosome(s). 94009/5-4 (2n = 45) had three H. villosa chromosomes (2, 3 and 4); 94009/5-8 (2n = 45) possessed one chromosome 4 and a pair of chromosome 5, and 94009/5-9 (2n = 43) was found to have one chromosome 6 of H. villosa. The combination of GISH with C-banding described here provides a direct comparison of the cytological and molecular landmarks. Such a technique is particularly useful for identifying and localizing alien chromatin and DNA sequences in plants.

An amylose was isolated from "Ban Xia", the dried tuber of Pinellia ternata, which demonstrated marked anti-inflammatory activity in mice at 25 mgAg. This amylose demonstrated nmr characteristics consistent with a standard amylose of a molecular weight of 4,100, which also demonstrated antiinflammatory activity in the same potency range as the isolated product from "Ban Xia" in mice.