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71.
Trehalose, the insect blood sugar, was found to inhibit diacylglycerol uptake by lipophorin from the fat body in vitro. Trehalose inhibited diacylglycerol uptake by about 40%-50% at various physiological concentrations. This suggests that trehalose may play a dual role in the hemolymph, i.e. serving as the insect's fuel and as a regulator in lipid transport. 相似文献
72.
A crude extract from taste buds was prepared from circumvallate papillae of bovine tongues by a procedure consisting of freezing, coring, excision, treatment with hypotonic buffer, nitrogen pressurization and selective homogenization. Examination of taste buds by light and electron microscopy before and after this procedure indicated that some of the contents of the buds, mainly from the more apical portions, was extruded following the procedure; anatomical changes could not be observed in the epithelial tissue immediately surrounding the taste buds. 相似文献
73.
74.
Retroviruses produced from the quail packaging cell line SE21Q1b predominantly contain cellular RNAs instead of viral RNAs. These RNAs can be reverse transcribed and integrated into the genomes of newly infected cells and are thereafter referred to as newly formed retrogenes. We investigated whether retrogene formation can occur within SE21Q1b cells themselves and whether this occurs intracellularly or via extracellular reinfection. By using packaging cell line mutants derived from the SE21Q1b provirus and selectable reporter constructs, we found that the process requires envelope glycoproteins and a retroviral packaging signal. Our results suggest that extracellular reinfection is the primary route of retrotransposition of nonviral RNAs. 相似文献
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76.
Morgane Sonia Thion Donovan Low Aymeric Silvin Jinmiao Chen Pauline Grisel Jonas Schulte-Schrepping Ronnie Blecher Thomas Ulas Paola Squarzoni Guillaume Hoeffel Fanny Coulpier Eleni Siopi Friederike Sophie David Claus Scholz Foo Shihui Josephine Lum Arlaine Anne Amoyo Anis Larbi Sonia Garel 《Cell》2018,172(3):500-516.e16
77.
Fragmented and scrambled mitochondrial ribosomal RNA coding regions among green algae: a model for their origin and evolution 总被引:4,自引:1,他引:3
Mitochondrial ribosomal RNA coding regions in the only three green algal
taxa investigated to date are fundamentally different in that they are
continuous in Prototheca wickerhamii, but highly fragmented and scrambled
in Chlamydomonas reinhardtii and Chlamydomonas eugametos. To gain more
insight into the mode of evolution of fragmented and scrambled
mitochondrial ribosomal RNA (rRNA) genes within the green algal group, this
work (1) provides additional information on fragmentation patterns of
mitochondrial small- and large-subunit (SSU and LSU) rRNAs that strongly
supports the concept of a gradual increase in the extent of discontinuity
of mitochondrial rRNAs among chlorophycean green algae and (2) reports the
first example of fragmented and scrambled mitochondrial LSU rRNA coding
regions in a green algal taxon outside the Chlamydomonas group. The present
study (1) suggests that the scrambling of the mitochondrial rRNA coding
regions may have occurred early in the evolution of fragmented and
scrambled mitochondrial rRNA genes within the chlorophycean green algal
group, most likely in parallel with the fragmentation events, (2) proposes
recombination as a possible mechanism involved in the evolution of these
mitochondrial rRNA genes, and (3) presents a hypothetical pathway for
converting continuous mitochondrial rRNA genes into the highly fragmented
and scrambled rRNA coding regions of Chlamydomonas through a series of
recombinatorial events between short repeated sequences.
相似文献
78.
79.
Similarity in Several Properties of Psychrophilic Bacteria Grown at Low and Moderate Temperatures 总被引:4,自引:2,他引:2 下载免费PDF全文
Hilmer A. Frank Ann Reid Leatrice M. Santo Norma A. Lum Sandra T. Sandler 《Applied microbiology》1972,24(4):571-574
Several properties of psychrophilic pseudomonads were studied with cells grown in batch culture in nutrient broth at 2 and 30 C. No differences were observed in the size, catalase activity, deoxyribonucleic acid, ribonucleic acid, or protein content of cells grown at either temperature. The importance of comparing physiologically similar cells is discussed. 相似文献