Kinetic Studies on the Transport of Cytoplasmically Synthesized Proteins into the Mitochondria in Intact Cells of Neurospora crassa

The transport of cytoplasmically synthesized mitochondrial proteins was investigated in whole cells of Neurospora crassa, using dual labelling and immunological techniques. In pulse and pulse-chase labelling experiments the mitochondrial proteins accumulate label. The appearance of label in mitochondrial protein shows a lag relative to total cellular protein, ribosomal, microsomal and cytosolic proteins. The delayed appearance of label was also found in immunoprecipitated mitochondrial matrix proteins, mitochondrial ribosomal proteins, mitochondrial carboxyatractyloside-binding protein and cytochrome c. Individual mitochondrial proteins exhibit different labelling kinetics. Cycloheximide inhibition of translation does not prevent import of proteins into the mitochondria. Mitochondrial matrix proteins labelled in pulse and pulse-chase experiments can first be detected in the cytosol fraction and subsequently in the mitochondria. The cytosol matrix proteins and those in the mitochondria show a precursor-product type relationship. The results suggest that newly synthesized mitochondrial proteins exist in an extra-mitochondrial pool from which they are imported into the mitochondria

Kinetic Studies on the Transport of Cytoplasmically Synthesized Proteins into the Mitochondria in Intact Cells of Neurospora crassa

The transport of cytoplasmically synthesized mitochondrial proteins was investigated in whole cells of Neurospora crassa, using dual labelling and immunological techniques. In pulse and pulse-chase labelling experiments the mitochondrial proteins accumulate label. The appearance of label in mitochondrial protein shows a lag relative to total cellular protein, ribosomal, microsomal and cytosolic proteins. The delayed appearance of label was also found in immunoprecipitated mitochondrial matrix proteins, mitochondrial ribosomal proteins, mitochondrial carboxyatractyloside-binding protein and cytochrome c. Individual mitochondrial proteins exhibit different labelling kinetics. Cycloheximide inhibition of translation does not prevent import of proteins into the mitochondria. Mitochondrial matrix proteins labelled in pulse and pulse-chase experiments can first be detected in the cytosol fraction and subsequently in the mitochondria. The cytosol matrix proteins and those in the mitochondria show a precursor-product type relationship. The results suggest that newly synthesized mitochondrial proteins exist in an extra-mitochondrial pool from which they are imported into the mitochondria

Zur Stratigraphie und Tektonik an der Nordostflanke des Elbingeröder Komplexes (Harz)

kein Abstract vorhandenno abstract availabl

Long-term additions of ammonium nitrate to montane forest ecosystems may cause limited soil acidification, even in the presence of soil carbonate

Nitrogen (N) deposition has decreased in the last decades in Europe but in many cases remains higher than the critical loads, i.e., higher than what could be considered safe for biodiversity and ecosystem functioning. The main concerns about N deposition are eutrophication and acidification. In a long-term experiment (1994 to present) in a montane (1200 m a.s.l.) coniferous forest in Alptal, central Switzerland, we simulated increased N deposition by adding NH4NO3 to rainwater. This treatment consisted of an additional N input of 22 kg ha−1 yr−1 to the 12 kg ha−1 yr−1 ambient bulk deposition rate or 17 kg N ha−1 yr−1 throughfall rate. The treatment was applied simultaneously to a small catchment area and to plots in a replicated block experiment (n=5). The site has a carbonate-rich parent material and is thus not particularly at risk of acidification. Nevertheless, we examined soil acidification as affected both by ambient and experimentally increased N deposition. In the 2.5 decades since the beginning of the study, nitrate (NO3-) and especially sulfate (SO42-) concentrations decreased in precipitation, while pH increased by slightly more than 1 unit. In the same time period a reduction in pH of the soil was measured. The exchangeable acidity in the soil increased, especially in the N-addition treatment. This was mainly observed on small mounds because the drier mounds are less well buffered than wet depressions. This trend, however, was limited in time, as exchangeable acidity later declined again to reach values not much higher than 26 years before. This was also the case in the N-addition treatment and can be considered a progressive recovery mainly due to the reduced acid inputs and, at this site with a carbonate-rich subsoil, to the biological cycling of base cations. The pH of the runoff from the experimental catchments decreased by 0.3 units, both in the control and under N addition. Decreasing Ca2+ and increasing Al3+ and Fe2+ concentrations in runoff also show that the recovery observed in the exchangeable soil acidity is not yet able to stop the slow acidification of water leaving the catchments. However, with the runoff water pH remaining above 7, this trend is not alarming for water quality or for the health of water bodies. Future monitoring will be necessary to see if and when a recovery takes place in the soil and runoff pH.</p

Учебный комплекс для изучения русского языка как иностранного (РКИ) "В добрый путь!" и компьютерный тренажер по РКИ

A description of the nationally oriented training complex for learning Russian as a foreign language "V Dobryi Put’!" for German speakers which includes a textbook, an audio-supplement, a video-film and a test system is given. The computer-based training system, designed for this complex ensures effective teaching foreign students Russian phonetics, vocabulary, grammar, speech etiquette, and also facilitates the formation of the necessary communication skills.Приводится описание национально-ориентированного учебного комплекса по РКИ для немецкоговорящих "В добрый путь!", который включает учебник, аудиоприложение, видеофильм и систему тестов. Разработанный для данного комплекса компьютерный тренажер обеспечивает эффективное обучение иностранных учащихся русской фонетике, лексике, грамматике, речевому этикету, а также облегчает формирование необходимых коммуникативных навыков