Mammalian cells

Organogenesis is crucial for proper organ formation during mammalian embryonic development. However, the similarities and shared features between different organs and the cellular heterogeneity during this process at single-cell resolution remain elusive.

20p vimichaelfaraday 25-03-2022 20 1   Download

A novel vector platform for vitamin H-inducible transgene expression in mammalian cells have therefore designed a strategy to convert antibiotic-responsive transcription factors into gene regulation systems responsive to non-toxic biotin, also known as vitamin H.

9p thuyancn 01-06-2015 43 5   Download

The transcription factor serum response factor (SRF) regulates expression of growth factor-dependent genes and muscle-specific genes in vertebrates. Homologous factors regulate differentiation of some ectodermic tissues in invertebrates. To explore the molecular basis of these different physiological functions, the functionality of human, Drosophila melanogaster and Artemia franciscana SRFs in mammalian cells has been compared in this article. D. melanogaster and, to a lesser extend, A.

9p system191 01-06-2013 32 5   Download

The gene fprA of Mycobacterium tuberculosis, encoding a putative protein with 40% identity to mammalian adrenodoxin reductase, was expressed in Escherichia coli and the protein purified to homogeneity. The 50-kDa protein monomer contained one tightly bound FAD, whose fluorescence was fully quenched. FprA showed a low ferric reductase activity, whereas it was very active as a NAD(P)H diaphorase with dyes. Kinetic parameters were determined and the specificity constant (kcat/Km) for NADPH was two orders of magnitude larger than that of NADH....

9p system191 01-06-2013 36 3   Download

The heterogeneous nuclear ribonucleoprotein (hnRNP) type I, a modulator of alternative splicing, localizes in the nucleoplasm of mammalian cells and in a discrete perinucleolar structure. HnRNP I contains a novel type of bipartite nuclear localization signal (NLS) at the N-terminus of the protein that we have previously named nuclear determinant localization type I (NLD-I). Recently, a neural counterpart of hnRNP I has been identified that contains a putative NLS with two strings of basic amino acids separated by a spacer of 30 residues....

8p system191 01-06-2013 25 3   Download

Manganese lipoxygenase was isolated to homogeneity from the take-all fungus, Gaeumannomyces graminis. The C-terminal amino acids and several internal peptides were sequenced, and the information was used to obtain a cDNA probe by RT/PCR. Screening of a genomic library of G. graminis yielded a full-length clone of the Mn-Lipoxygenase gene. cDNA analysis showed that the gene spanned 2.6 kb and contained one intron (133 bp). Northern blot analyses indicated two transcripts (2.7 and 3.1 kb). The deduced amino-acid sequence of the Mn-Lipoxygenase precursor (618 amino acids, 67.

8p system191 01-06-2013 36 4   Download

Nuclear cloning is a procedure to create new animals by injecting somatic nuclei into unfertilized oocytes. Recent successes in mammalian cloning with differentiated adult nuclei strongly indicate that oocyte cytoplasm contains unidentified remarkable reprogramming activities with the capacity to erase the previous memory of cell differentiation. At the heart of this nuclear reprogramming lies chromatin remodeling as chromatin structure and function define cell differentiation through regulation of the transcriptional activities of the cells....

4p research12 01-06-2013 42 4   Download

In avian species, an egg envelope homologous to the mammalian zona pellucida is called the perivitelline membrane. We have previously reported that one of its components, a glycoprotein homologous to mammalian ZPC, is synthesized in the granulosa cells of the quail ovary. In the present study, we investigated the proteolytic cleavage of the newly synthesized ZPC and the secretion of ZPC from the granulosa cells. Western blot analysis of the cell lysates demonstrated that the 43-kDa protein is the precursor of mature ZPC (proZPC), and is converted to the 35-kDa protein before secretion. ...

9p research12 01-06-2013 36 4   Download

A severe challenge to the idea that mitochondrial DNA mutations play a major role in the aging process in mammals is that clear loss-of-function mutations accumulate only to very low levels (under 1% of total) in almost any tissue, even by very old age. Their accumulation is punctate: some cells become nearly devoid of wild-type mitochondrial DNA and exhibit no activity for the partly mitochondrially encoded enzyme cytochrome c oxidase. Such cells accumulate in number with aging, suggesting that they survive indefinitely, which is itself paradoxical....

7p research12 01-06-2013 27 3   Download

Antizyme is a polyamine-induced cellular protein that binds to ornithine decarboxylase (ODC), and targets it to rapid ubiquitin-independent degradation by the 26S proteasome. However, the metabolic fate of antizyme is not clear. We have tested the stability of antizyme in mammalian cells. In contrast with previous studies demonstrating stability in vitro in a reticulocyte lysate-based degradation system, in cells antizyme is rapidly degraded and this degradation is inhibited by specific proteasome inhibitors. ...

7p research12 01-06-2013 40 3   Download

Lipid rafts are liquid-ordered membrane microdomains with a unique protein and lipid composition found on the plasma membrane of most, if not all, mammalian cells. A large number of signalling molecules are concentrated within rafts, which have been proposed to function as signalling centres capable of facilitating efficient and specific signal transduction. This review summarizes current knowledge regarding the composition, structure, and dynamic nature of lipid rafts, as well as a number of different signalling path- ways that are compartmentalized within these microdomains....

16p research12 01-06-2013 37 3   Download

The Na + /H + exchanger is a ubiquitous membrane protein of bacteria, plants and mammals. The first isoform discov-ered (NHE1) is present on the mammalian plasma mem-brane and transports oneH + out of cells inexchange for one extracellular Na + . With solubilization in standard SDS/ PAGE buffer, this protein had a high tendency to aggregate when subjected to elevated temperature. The aggregates were stable and did not dissociate in high concentrations of SDSor 2-mercaptoethanol.

9p research12 29-04-2013 46 3   Download

Extracellular cleavage of virus envelope fusionglycoproteins by host cellular proteases is a prerequisite for the infectivity of mammalian and nonpathogenic avian influenza viruses, and Sendai virus. In search of such target processing pro-teases in the airway, we recently found a new candidate trypsin-like processing protease in rat lungs, which was induced by Sendai virus infection, and identified as ectopic rat anionic trypsin I.

9p research12 29-04-2013 40 4   Download

Dj2 is a member of the DnaJ family of proteins, which regulate the chaperoning functionof the hsp70s.We isolated a monkey cDNA dj2 clone corresponding to the large mRNA species encoded by the gene. This mRNA differs from the small mRNAproduced by the same gene in that it contains a long 3¢ untranslated region. Both messages were found to be equally stable and to produce the same protein, which is susceptible to farnesylation.

8p research12 29-04-2013 34 3   Download

Stimulation with granulocyte colony-stimulating factor (G-CSF) induces myeloid precursor cells to di€erentiate into neutrophils, and tyrosine phosphorylation of certain cellular proteins is crucial to this process. However, the signaling pathways for neutrophil di€erentiation are still obscure. As the Src-like tyrosine kinase, Lyn, has been reported to play a role in G-CSF-induced proliferation in avian lymphoid cells, we examined its involvement in G-CSF-induced signal transduction in mammalian cells....

9p research12 29-04-2013 35 4   Download

Eosinophil cationic protein (ECP), one of the major components of basic granules of eosinophils, is cytotoxic to tracheal epithelium. However, the extent of this e€ect on other cell types has not been evaluatedin vitro.Inthis study, we evaluated the e€ect of ECP on 13 mammalian cell lines. ECP inhibited the growth of several cell lines including those derived from carcinoma and leukemia in a dose-dependent manner.

10p research12 29-04-2013 36 4   Download

A putativeDrosophilanucleotide sugar transporter was characterized and shown to be theDrosophilahomologue of the human UDP-Gal transporter (hUGT). When the Drosophila melanogasterUDP-Gal transporter (DmUGT) was expressed in mammalian cells, the transporter protein was localized in the Golgi membranes and complemented the UDP-Gal transport de®ciency of Lec8 cells but not the CMP-Sia transport de®ciency of Lec2 cells.

11p research12 29-04-2013 30 2   Download

N-Acetylglucosamine is a major component of com-plex carbohydrates. The mammalian salvage pathway of N-acetylglucosamine recruitment from glycoconjugate deg-radation or nutritional sources starts with phosphorylation byN-acetylglucosamine kinase. In this studywe describe the identification of two active site cysteines of the sugar kinase by site-directed mutagenesis and computer-based structure prediction.

7p research12 23-04-2013 33 2   Download

Hsp105aisoneof themajormammalianheat shockproteins that belongs to the HSP105/110 family, and is expressed at especially high levels in the brain as compared with other tissues in mammals. Previously, we showed that Hsp105a prevents stress-induced apoptosis in neuronal PC12 cells, and is a novel anti-apoptotic neuroprotective factor in the mammalian brain.

9p research12 23-04-2013 40 1   Download

Substrate properties of xanthine (Xan) and xanthosine (Xao) for purine nucleoside phosphorylases (PNP) of mammalian origin have been reported previously, but only at a single arbitrarily selected pH and with no kinetic con-stants. Additionally, studies have not taken into account the fact that, at physiological pH, Xao (pKa¼5.7) is a mono-anion, while Xan (pKa¼7.7) is an equilibrium mixture of the neutral and monoanionic forms.

10p research12 23-04-2013 40 2   Download