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81.
M. Zamirul Hussain John C. Belton Rajendra S. Bhatnagar 《In vitro cellular & developmental biology. Plant》1978,14(9):740-745
Organ cultures of newborn rat lungs synthesize and accumulate DNA, RNA, collagen and noncollagenous proteins almost at a linear
rate for at least 5 days. During this period the synthesis of collagen consistently exceeds the synthesis of noncollagenous
proteins in a pattern similar to neonatal lung growth in vivo. Although some morphological characteristics of lung architecture
are distorted after culture, fundamental structural similarities to lungs growing in intact animals are retained. When these
cultures are maintained in atmospheres rich in oxygen, increased collagen synthesis is observed, a response similar to that
of lungs in intact animals exposed to high oxygen concentrations in vivo. Our studies suggest that lung organ cultures may
be a suitable system for investigating the biochemical aspects of lung tissue-environmental interaction.
These studies were supported in parts by NIH Grant HL-19668, a contract (68-03-2005) from the U.S. Environmental Protection
Agency, and grants from the California Lung Association. 相似文献
82.
83.
Nataly Mancette Rijensky Netta R. Blondheim Shraga Eilon Barnea Nir Peled Eli Rosenbaum Aron Popovtzer Solomon M. Stemmer Alejandro Livoff Mark Shlapobersky Neta Moskovits Dafna Perry Eitan Rubin Itzhak Haviv Arie Admon 《Molecular & cellular proteomics : MCP》2020,19(8):1360-1374
Highlights
- •Sufficient tumor tissues are often unavailable large HLA peptidome discovery.
- •Using patient derived xenograft (PDX) tumors can overcome this limitation.
- •The large PDX HLA peptidomes expand significantly those of the original biopsies.
- •The HLA peptidomes of the PDX tumors included many tumor antigens.
84.
Abstract The bifunctional T-protein (chorismate mutase-T: cyclohexadienyl dehydrogenase) of l -tyrosine biosynthesis was found to be present in all genera making up the enteric bacteria. The dehydrogenase component of the T-protein was active with both prephenate and l -arogenate, showing it to be a cyclohexadienyl dehydrogenase. The dehydrogenase component, but not the mutase component, of the T-protein was feedback-inhibited by l -tyrosine. Unlike some other bifunctional proteins, the T-protein has evolved recently and is not ubiquitous. However, once the biochemical specialization of bifunctionality becomes established, the results indicate that such character states are strongly conserved through evolutionary time. Thus, bifunctional proteins can provide particularly reliable markers for small (recent origin), intermediate, and large (ancient origin) phylogenetic clusters. 相似文献
85.
Because the acrosome of human sperm is too small to be directly visualized by phase-contrast microscopy, acrosome reactions (that is loss of the acrosome) are generally not evaluated in studies of human sperm capacitation and fertilization. Nevertheless, it would be useful in such studies to have a technique for easily identifying and quantitating acrosome-reacted sperm. In this paper, we describe a method for labeling the human sperm acrosome with fluorescein-conjugated Ricinus communis agglutinin-60 (FITC-RCA); we show that in sperm without acrosomal caps, FITC-RCA labeling occurs either not at all or only in the equatorial segment of the acrosome. To determine if the absence of FITC-RCA labeling in the acrosomal cap region gives a reliable estimate of acrosome reactions, washed sperm or sperm incubated in a capacitating medium (BWW) were divided into two groups, which were then fixed for FITC-RCA labeling or transmission electron microscopy. Counts of acrosome reactions made by each method were similar, and we observed an increase in the percentage of reactions following incubation in BWW. We conclude that the FITC-TCA labeling technique is a reliable method for accurately scoring the percentage of acrosome-reacted human sperm. 相似文献
86.
Pertti J. Martikainen Eeva-Liisa Nurmiaho-Lassila Kari Lounatmaa 《FEMS microbiology letters》1989,59(3):313-317
Abstract The outer membrane (OM) structure of Nitrosospira sp. X101 was studied by different electron microscopic techniques and SDS-PAGE. A crystalline outer membrane protein was visible in freeze-etched cells, occasionally seen also in the thin sectioned cells, but was difficult to see in a negatively-stained preparation. The lattice probably consists of large globular protein subunits with a hexagonal arrangement. The molecular weights of the major proteins in the cell envelope are 35 kDa, 40 kDa and 42 kDa. 相似文献
87.
Sixteen enzymatic and non-enzymatic proteins of the pigeon Columba livia domestica were examined electrophoretically. These proteins were presumed to be under control by 22 loci. Of the 22 loci, 6 were defined as polymorphic and 15 as monomorphic. Another locus was variable, but the variation was not genetically interpretable. Average heterozygosity calculated over 21 loci was 0.075. 相似文献
88.
Cytokinin-binding proteins 总被引:3,自引:0,他引:3
This article is focused on the modalities of reception of cytokinins which remain largely unknown. It summarizes the main steps of the different protocols used to study cytokinin-binding proteins (CBPs). We place emphasis on the significance and specificity of the detection according to the properties of the probes used: radioactive or photoreactive cytokinins, fluorescent anticytokinins, anti-idiotype antibodies. The purification procedures are also examined. The cellular localisation and the putative physiological roles of the numerous and different CBPs found are considered. The interest of genetic and molecular studies is discussed. 相似文献
89.
Jason A. SOMARELLI Annia MESA Ambrish ROY Yang ZHANG Rene J. HERRERA 《Entomological Research》2010,40(2):104-112
Most of the pre-mRNAs in the eukaryotic cell are comprised of protein-coding exons and non-protein-coding introns. The introns are removed and the exons are ligated together, or spliced, by a large, macromolecular complex known as the spliceosome. This RNA-protein assembly is made up of five uridine-rich small nuclear RNAs (U1-, U2-, U4-, U5- and U6-snRNA) as well over 300 proteins, which form small nuclear ribonucleoprotein particles (snRNPs). Initial recognition of the 5′ exon/intron splice site is mediated by the U1 snRNP, which is composed of the U1 snRNA as well as at least ten proteins. By combining structural informatics tools with the available biochemical and crystallographic data, we attempted to simulate a complete, three dimensional U1 snRNP from the silk moth, Bombyx mori. Comparison of our model with empirically derived crystal structures and electron micrographs pinpoints both the strengths and weaknesses in the in silico determination of macromolecular complexes. One of the most striking differences between our model and experimentally generated structures is in the positioning of the U1 snRNA stem-loops. This highlights the continuing difficulties in generating reliable, complex RNA structures; however, three-dimensional modeling of individual protein subunits by threading provided models of biological significance and the use of both automated and manual docking strategies generated a complex that closely reflects the assembly found in nature. Yet, without utilizing experimentally-derived contacts to select the most likely docking scenario, ab initio docking would fall short of providing a reliable model. Our work shows that the combination of experimental data with structural informatics tools can result in generation of near-native macromolecular complexes. 相似文献
90.
zge Karayel Francesca Tonelli Sebastian Virreira Winter Phillip E. Geyer Ying Fan Esther M. Sammler Dario R. Alessi Martin Steger Matthias Mann 《Molecular & cellular proteomics : MCP》2020,19(9):1546-1560
Highlights
- •MS-based clinical assay that accurately determines phospho Rab10 occupancy.
- •Stable isotope labeled phosphopeptide injected as a standard with endogenous tryptic phospho Rab peptide for accurate ratio determination.
- •Determination of pRab levels in neutrophils of Parkinson disease patients.
- •Relevance of pRab levels as marker of PD.