CHLPEP—A database of chloroplast transit peptides

Transit peptides are N-terminal extensions that serve to route nuclearencoded proteins into chloroplasts. We have collected amino acid sequences for approximately 260 transit peptides, and have constructed a database that presently runs under FileMaker Plus on Macintosh personal computers. In addition, the collection is available as an ASCII-file, either in a tab-delimited format suitable for import into other database programs, or in a format with line-identifiers similar to the widely used Swiss Prot database. We hope that the plant molecular biology community will help us ensure that the collection is kept up to date by submitting new sequences directly to us.     

A new assay method for lipid peroxides using a methylene blue derivative

To determine the absolute amount of lipid hydroperoxides in biological materials, a simple and sensitive colorimetric method was newly developed, based on the reaction of lipid hydroperoxides with a leucomethylene blue derivative in the presence of hemoglobin. The amount of methylene blue formed was measured by its absorbance at 666 nm to calculate the amount of lipid hydroperoxides using cumene hydroperoxide as external standard. By this method, lipid hydroperoxide concentrations of less than 7.5 nmol/tube were accurately determined.     

A 900 bp genomic region from the mouse dystrophin promoter directs lacZ reporter expression only to the right heart of transgenic mice

In order to study the regulatory mechanism of developmental and tissue-specific expression of the muscle type dystrophin gene in mice, transgenic mice were generated carrying the 900 bp genomic fragment derived from the muscle type dystrophin promoter region fused to the bacterial lacZ gene. Six independent transgenic mouse lines showed specific reporter gene expression in the right heart, but not in skeletal or smooth muscle. The reporter gene expression was first detected in the presumptive right ventricle of the embryos at 8.5 days post coitum, and the expression continued only in the right ventricle throughout the development and at the adult stage. The results indicate that the 900 bp genomic fragment contains the regulatory element required for expression of dystrophin only in the right heart, suggesting that distinct elements are responsible for the expression in the left and right compartments of the heart, and/or in skeletal and smooth muscle cells. Based on these findings, the relationship between defects in muscle type promoter and the diseases caused by abnormal dystrophin expression is discussed.     

The Fate of Thiophanate-methyl Fungicide and Its Metabolites on Plant Leaves and Glass Plates

The persistence of thiophanate-methyl, dimethyl 4, 4′-o-phenylenebis (3-thioallophanate), and its metabolites on plant leaves and glass plates was examined using a radiolabeled compound. Apple and grape leaves and glass plates treated with thiophanate-methyl-phenyl-¹⁴C were kept outdoors, except on rainy days and nights when they were kept in green house.

Half lives of thiophanate-methyl on apple and grape leaves were around 15 and 12 days, respectively. On glass plates half life was around 3 days. The per cent of abundance of the parent compound and a major degraded product, methyl 2-benzirnidazolecarbamate, versus applied thiophanate-methyl at 14 days after treatment was as follows; 52.6 and 10.1% on apple leaves, 49.5 and 8.9% on grape leaves, and 5.5 and 24.1% on glass plates, respectively.     

Plant regeneration from protoplasts of common buckwheat (fagopyrum esculentum)

Protoplasts were isolated from hypocotyls of etiolated seedlings from a diploid and the corresponding autotetraploid variety of common buckwheat (Fagopyrum esculentum). The isolated protoplasts started to divide after 4 days in culture in a modified MS medium. Maximum plating efficiency was approximately 1%. Regenerated calli derived from the tetraploid genotype developed roots easily but were recalcitrant to form shoots. Eighteen months following the initiation of cultures, tetraploid embryoids and shoots emerged after 3 weeks on an MS medium containing 0.1 mg/l gibberellic acid.Abbreviations 2,4-D 2,4 — dichlorophenoxyacetic acid - BAP 6-benzylaminopurine - GA gibberellic acid - MS Murashige and Skoog (1962) medium - NAA 1-naphthaleneacetic acid