Changes in the Activity of the Maturation-Promoting Factor Are Correlated with Those of a Major Cyclic AMP and Calcium-Independent Protein Kinase During the First Mitotic Cell Cycles in the Early Starfish Embryo

Many studies suggest that MPF activation depends on protein phosphorylation or that MPF is itself a protein kinase. In the present report, cyclic variations of MPF activity have been correlated in vivo with changes in the extent of protein phosphorylation or in vitro with changes of a major protein kinase during the first cell cycles of fertilized starfish eggs. This cycling protein kinase neither requires cAMP nor Ca²⁺. Neither colchicine nor aphidicoline, which inhibits cleavage and chromosome replication respectively, was found to suppress the synchronous and cyclic variations of both MPF and protein kinase activities. Protein synthesis was found to be required for both MPF and protein kinase activities to reappear after their simultaneous drop at the time of mitotic or meiotic cleavages. Production of either MPF or protein kinase activities is not the immediate result of protein synthesis since there is a delay at each cell cycle between the time when protein synthesis is required and the time when both MPF and protein kinase activities are produced. This suggests that both MPF and protein kinase activities might involve some post-translational modification of a precursor protein synthesized during the preceeding cell cycle.     

P-transposable vectors expressing a constitutive and thermoinducible hsp82-neo fusion gene for Drosophila germline transformation and tissue-culture transfection

Three P-transposable vectors (approx. 16, 12, and 9 kb) were constructed containing a hsp82-neo fusion gene encoding a truncated heat-shock protein 82 of Drosophila pseudoobscura and the bacterial neomycin phosphotransferase (NPT). In transgenic Drosophila melanogaster, hsp82-neo exhibits high levels of housekeeping gene promoter and NPT activities in all cells in the absence of heat-shock and is further induced (fivefold) by elevated temperatures (35 degrees-36 degrees C). The hsp82-neo selection of transformants is possible from embryo to adulthood. The hsp82-neo insertion in a P-element plasmid carrying an alcohol-dehydrogenase-encoding gene (Adh) produced plasmids pHS22 (approx. 16 kb) and pHS24 (approx. 12 kb), in which both genes were expressed, as observed in 13 transgenic strains. Cloning of DNA fragments up to at least 16 kb in a third vector, pHS85 (approx. 9 kb), lacking the Adh cointegrate is facilitated by a 104-bp multiple cloning site (MCS) positioned downstream (3') from hsp82-neo. To accept inserts of nonselectable foreign genes, MCS provides 20 restriction sites, eight of them unique. The hsp82-neo-expressing vectors also function in cell-culture transfection assays. The hsp82-neo fusion gene (3.73 kb) may be of wide application as a dominant selection marker in other animal systems and plants.     

中国平脉树螽属五新种记述：直翅目：螽斯科：树螽亚科

本文报道中国平脉树螽属5个新种。每个新种皆有详细的形态描述和形态特征图。所有模式标本存于北京农业大学昆虫标本室。     

Bizarre atypia in gastric brushings associated with hepatic arterial infusion chemotherapy

Hepatic arterial infusion chemotherapy (HAIC) for unresectable hepatic neoplasms has been associated with gastric ulcers and epithelial atypia that may be misinterpreted as carcinoma. Gastric brushings were reviewed from six patients who developed gastric ulcers with histologically proven atypia following HAIC. Marked cytologic atypia, reminiscent of a pronounced radiation effect, was present in gastric epithelial cells in five patients. The atypical cells occurred singly or in small sheets. They were markedly enlarged but a low nuclear-cytoplasmic ratio was preserved. The abundant cytoplasm was vacuolated or foamy. Binucleation and multinucleation were common, and massive nucleoli were characteristic. The brushings also contained the reparative, inflammatory and necrotic changes associated with usual benign gastric ulcers. The bizarre atypia associated with HAIC can be a source of misdiagnosis of cancer in cytologic as well as in histologic specimens.     

Changes in Abscisic Acid Content in Axis and Cotyledons of Developing Phaseolus vulgaris Embryos and their Physiological Consequences

Prevost, I. and Le Page–Degivry, M. Th. 1985. Changesin absicisic acid content in axis and cotyledons of developingPhaseolus vulgaris embryos and their physiological consequences.—J.exp. Bot. 36: 1900–1905.Changes in abscisic acid (ABA)content with time were measured in embryonic axes and in cotyledonsof Phaseolus vulgaris embryos using a radio–immunoassay.During embryogenesis, a similar pattern was observed in bothtissues: ABA increased to a maximum 29 d after an thesis, followedby a decrease as the seed matured. The level of ABA in the cotyledonswas always much higher than that in the axes. In in vitro cultures,the duration of the lag phase before germination of isolatedembryonic axes increased with ABA content. The presence of cotyledonsalways lengthened the lag phase; longer lag phases were associatedwith greater concentrations of ABA in the cotyledons. Moreoverthe presence of cotyledons stimulated the growth of seedlings. Key words: ABA distribution, embryo maturation, axis and embryo germinability