Showing papers in "Cell in 1980"

TL;DR: Ulastructural examination of cells cultured under low Ca++ conditions reveals widened intercellular spaces, abundant microvilli and perinuclear organization of tonofilaments and cellular organelles.

TL;DR: Results provide experimental evidence for a role for DNA modification in differentiation, and suggest that cytidine analogs containing an altered 5 position perturb previously established methylation patterns to yield new cellular phenotypes.

TL;DR: Electron microscopy of sec mutant cells reveals the temperature-dependent accumulation of membrane-enclosed secretory organelles, and it is suggested that these structures represent intermediates in a pathway in which secretion and plasma membrane assembly are colinear.

TL;DR: Bacterial clones containing inserted DNA sequences specific for α- Tubulin, β-tubulin,β-Actin and γ-actin have been constructed from mRNA of embryonic chick brain and are able to hybridize under stringent conditions to DNA of all vertebrates tested, as well as to sea urchin DNA, but not to yeast DNA.

TL;DR: The precise dissection of cellular mechanisms and interactions involved in the generation of human T cell responses has been facilitated in recent years by advances in four areas: first, the development of in this paper.

TL;DR: A model for the involvement of short direct repeat sequences in the generation of deletions in the noncoding and coding regions of B-like globin genes during evolution is described.

TL;DR: Direct microinjection of DNA by glass micropipettes was used to introduce the Herpes simplex virus thymidine kinase gene into cultured mammalian cells, and transformation frequency was relatively insensitive to DNA concentration and did not depend on co-injecting with a carrier DNA.

TL;DR: Stratified squamous epithelia of internal organs do not form a typical stratum corneum and do not make the large keratins characteristic of epidermis, implying that they have embarked on an alternate route of terminal keratin synthesis.

TL;DR: It is demonstrated by immunofluorescence microscopy that the lamina is reversibly disassembled during cell division, coincident with the disassembly and reconstruction of the mitotic nuclear envelope architecture, and that all three lamins are monomeric at periods of mitotic lamina disassembly.

TL;DR: The disposition of the contacts in space suggests a model for the pathway along which the RNA polymerase binds to promoters, as shown on three-dimensional models.

TL;DR: The sequence data suggest that intergenic conversions occur in the germ line, and strongly suggest that DNA sequence polymorphisms for localized deletions, additions and base substitutions are very common in human populations.

TL;DR: It is shown that both μ m and μ s mRNAs are produced from transcripts of a single μ gene, suggesting that developmental control of the site at which poly(A) is added to transcripts of the μ gene determines the relative levels of μ m or μ s chain synthesis.

TL;DR: A model for variable region gene rearrangement mediated by proteins which recognize the same conserved sequences adjacent to both light and heavy chain immunoglobulin gene segments is proposed.

TL;DR: Results suggest that ZP3 possesses the receptor activity responsible for the binding of sperm to zonae pellucidae of unfertilized mouse eggs, consistent with the inability of solubilized ZP1 and ZP2 from 2-cell embryos to affect sperm binding.

TL;DR: The cell type generated by retinoic acid and dibutyryl cAMP treatment is therefore indistinguishable from definitive parietal endoderm, and analysis of the final phenotype indicates that it is not dependent upon the continued presence of either compound, and that cAMP agents are active only on cells that have been treated with retinoi acid.

TL;DR: 2 microM CB strongly reduces the low shear viscosity of actin filaments alone and actin Filaments cross-linked by a variety of macromolecules, which may be due to inhibition of act in filament-filament interactions which normally contribute to network formation.

TL;DR: Measurements of the attachment of the PAM 212 line of mouse epithelial cells to various collagen substrates show that these cells adhere preferentially to type IV, basement membrane collagen, which suggests that lamin is produced and utilized by these epithelium cells to attach to basement membranes collagen.

TL;DR: Electron microscopic autoradiography shows that, as with intact nuclei, sites of DNA replication are distributed throughout the nuclear matrix, and a fixed site of DNA synthesis is proposed in which DNA replication complexes are anchored to thenuclear matrix.

TL;DR: It is shown that after depleting interphase nuclei of histones and other nuclear proteins by treatment with nonionic detergent and high salt, intact loops of DNA can be visualized as a halo surrounding a nuclear skeleton or matrix, suggesting that the replicating DNA loops are motile with respect to their nuclear matrix anchorage sites.

TL;DR: A factor necessary for the accurate transcription of cloned Xenopus 5S genes in vitro has been isolated from soluble extracts of X. laevis ovaries and the site of action has been investigated using the "footprinting" method of Galas and Schmitz (1978).

TL;DR: Although the anaerobic polypeptides share a formal similarity to heat-shock proteins in animals, it is probable that theAnaerobic genes are an adaptation to flooding.

TL;DR: It is demonstrated that mum and mus heavy chains are encoded by separate mRNAs of 2.7 and 2.4 kb, respectively, and it is proposed that comparable C terminal segments also will be found in other membrane-bound immunoglobulin heavy chains.

TL;DR: It is concluded that not all of these sites are neutral and that they do not behave as accurate evolutionary clocks over long periods of time, but nucleotide substitutions leading to amino acid replacements are an excellent clock.

TL;DR: The physical properties, sequence divergence and chromosomal distribution of six different repeated sequences in Secale cereale (cultivated rye) are described and it is suggested that each of the S. cereale-specific repeats may have evolved by the insertion of DNA elements into an array of simple repeats followed by amplification of the portion of the array containing the inserted sequence.

TL;DR: It is concluded that a control region within the gene directs RNA polymerase III to initiate transcription approximately 50 nucleotides upstream from the 5' border of this region.

TL;DR: The results, taken together with the observation that cycloheximide has no effect on ligand uptake, suggest that receptors must be spared from degradation and that reutilization of receptors probably occurs.

TL;DR: Analysis of DNA modification in the human γδβ-globin gene region suggests that a low level of DNA methylation may be a necessary, but not a sufficient, condition for gene expression in higher eucaryotes.

TL;DR: It is demonstrated that the T4 DNA topoisomerase changes the linking number of a covalently closed double-stranded circular DNA molecule only by multiples of two, which indicates that this enzyme must act via mechanisms that involve the concerted cleavage and rejoining of two opposite DNA strands, such that the DNA double helix is transiently broken.

TL;DR: It was shown that the 3′ ends of the two μ mRNAs do not cross-hybridize, and apparently two separate 3′ terminal sequences for μ mRNA are encoded in the genome, one that specifies an amino acid sequence appropriate for membrane-binding and a second that is involved in secretion.