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C L Smith

Publications and source records attributed to C L Smith.

At least 271 records · Page 15Linked to original sources
PubMed1988

The effects of role-playing high gender identification on the California Psychological Inventory.

This study of the California Psychological Inventory (CPI) demonstrates that subjects can alter significantly their CPI profiles through role-playing high gender identification, i.e., males attempt to appear more masculine and women attempt to appear more feminine. The majority of these subjects did so without being detected by the validity scales designed to detect faking good or bad. Thirty-two volunteers, 16 male and 16 female, participated as subjects. A 2 X 2 ANOVA (subject gender by instructions to role-play vs. standard instructions) design was used. A significant main effect (p less than .01) for instructions was found on 14 of 18 scales and a significant interaction effect (p less than .01) on 4 of 18 scales. The profiles from the role-playing subjects indicate that the stereotypes of both genders, as seen by these subjects, are maladaptive. Implications for practical application of these findings are discussed.

Adaptation, Psychological↗
PubMed1988

Content and organization of the human Ig VH locus: definition of three new VH families and linkage to the Ig CH locus.

We present a detailed analysis of the content and organization of the human immunoglobulin VH locus. Human VH genes representing five distinct families were isolated, including novel members belonging to two out of three of the known VH gene families (VH1 and VH3) as well as members of three new families (VH4, VH5, and VH6). We report the nucleotide sequence of 21 novel human VH genes, many of which belong to the three new VH gene families. In addition, we provide a preliminary analysis of the organization of these gene segments over the full extent of the locus. We find that the five multi-segment families (VH1-5) have members interspersed over nearly the full 1500-2000 kb of the VH locus, and estimate that the entire heavy chain locus covers 2500 kb or less. Finally, we provide the first report of the physical linkage of the variable and constant loci of a human Ig gene family by demonstrating that the most proximal known human VH segments lie within 100 kb of the constant region locus.

Animals↗
PubMed1988

Mapping the genome.

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Base Composition↗
PubMed1988

Physical mapping of the cystic fibrosis region by pulsed-field gel electrophoresis.

The gene for cystic fibrosis (CF) is known to be flanked by the closely linked DNA markers met and J3.11 on chromosome 7. Using the technique of pulsed-field gel electrophoresis, we have constructed a complete overlapping restriction map of approximately 3000 kb of DNA in this region. The met and J3.11 probes are found to be between 1300 and 1800 kb apart, which compares well with their genetic distance of 1-2 cM. The CF gene must be located within this interval, and the availability of this physical map should be of considerable utility in mapping additional clones as the search for the gene proceeds.

Cell Line↗
PubMed1988

The 289-amino acid E1A protein of adenovirus binds zinc in a region that is important for trans-activation.

The E1A gene of adenovirus type 5 encodes two major proteins of 289 and 243 amino acid residues, which are identical except that the larger protein has an internal stretch of 46 amino acids required for efficient trans-activation of early viral promoters. This domain contains a consensus zinc finger motif (Cys-Xaa2-Cys-Xaa13-Cys-Xaa2-Cys) in which the cysteine residues serve as postulated ligands. Atomic absorption spectrophotometry applied to bacterially expressed E1A proteins revealed that the 289-amino acid protein binds one zinc ion, whereas the 243-amino acid protein binds no zinc. Replacing individual cysteine residues of the finger with other amino acids destroyed the trans-activating ability of the 289-amino acid protein, even when structurally or functionally conserved amino acids were substituted. These results strongly suggest that the zinc finger of the 46-amino acid domain is intimately linked to the ability of the large E1A protein to stimulate transcription of E1A-inducible promoters. Furthermore, zinc binding to one of the mutant finger proteins suggests either that only a precise finger structure formed by the tetrahedral coordination of zinc to the four consensus ligands is required for trans-activation or, possibly, that one of several neighboring histidine residues in various combinations with three of the consensus cysteine residues normally coordinates zinc. How the zinc finger in E1A might interact with DNA or protein to bring about trans-activation is discussed.

Adenovirus Early Proteins↗
PubMed1988

Mapping of Escherichia coli chromosomal Tn5 and F insertions by pulsed field gel electrophoresis.

A low resolution Not I physical map of Escherichia coli was recently constructed. In this report we demonstrated that this map can be used to map Tn5 and F insertions physically. The transposon, Tn5, contains Not I recognition sequences in its IS50 sequences. F plasmid contains an unmapped Not I site. Hence, the location of Tn5 and F in the chromosome can be mapped by identifying the location of the introduced Not I sites using pulsed field gel electrophoresis. The physical mapping of genetically mapped Tn5 insertions confirm the previously constructed Not I map and helps align the E. coli physical and genetic maps. The use of Tn5 can assist the construction of both physical and genetic maps for microorganisms lacking such maps. Variations on this approach will facilitate physical mapping with a wide variety of organisms, enzymes, and genetic elements.

Alleles↗
PubMed1988

Rapid and precise mapping of the Escherichia coli release factor genes by two physical approaches.

The termination of protein synthesis in Escherichia coli requires two codon-specific factors termed RF1 and RF2. RF1 mediates UAA- and UAG-directed termination, while RF2 mediates UAA- and UGA-directed termination. The genes encoding these factors have been isolated and sequenced, and RF2 was found to be encoded in two separate reading frames. The map position of RF1 has been reported as 27 min on the E. coli chromosome, while the RF2 map position has not yet been identified. In this study, two new and independent methods for gene mapping, using pulsed field gel electrophoresis and an ordered bacteriophage library spanning the entire chromosome, were used to localize the map position of the RF2 gene. In addition, the location of the RF1 gene was more precisely defined. The RF2 gene is located at 62.3 min on the chromosome, while the RF1 gene is located at 26.7 min. This approach to mapping cloned genes promises to be a rapid and simple means for determining the gene order of the genome.

Amino Acid Sequence↗
PubMed1988

Identity of the 17-kilodalton protein, a DNA-binding protein from Escherichia coli, and the firA gene product.

The 17-kilodalton protein, a DNA-binding protein encoded by the skp gene of Escherichia coli, was found to be identical to histonelike protein I, the product of the firA gene. This conclusion was reached after chromosomal localization, using the recently constructed high- and low-resolution E. coli restriction maps, and by direct comparison of the N-terminal amino acid sequence of histonelike protein I and the 17-kilodalton protein.

Chromosome Mapping↗
PubMed1988

Peripheral specification of sensory connections in the spinal cord.

During development, primary sensory neurons innervate peripheral targets and then form central connections appropriate to these targets. Sensory neurons induced to innervate novel peripheral targets by surgical manipulations in Rana catesbeiana tadpoles form central connections appropriate to their novel targets even when they must project into novel areas of the spinal cord to do so. The selectivity displayed by sensory neurons innervating different peripheral targets suggests that they may acquire distinctive biochemical properties from their targets that endow them with affinities for appropriate central neurons.

Animals↗
PubMed1987

A physical map of the Escherichia coli K12 genome.

A physical map of a genome is the structure of its DNA. Construction of such a map is a first step in the complete characterization of that DNA. The restriction endonuclease Not I cuts the genome of Escherichia coli K12 into 22 DNA fragments ranging from 20 kilobases (20,000 base pairs) to 1000 kilobases. These can be separated by pulsed field gel electrophoresis. The order of the fragments in the genome was determined from available E. coli genetic information and analysis of partial digest patterns. The resulting ordered set of fragments is a macrorestriction map. This map facilitates genetic and molecular studies on E. coli, and its construction serves as a model for further endeavors on larger genomes.

Chromosome Mapping↗
PubMed1987

A histidine-rich protein gene marks a linkage group favored strongly in a genetic cross of Plasmodium falciparum.

Two histidine-rich protein genes in Plasmodium falciparum are related by an ancestral duplication and interchromosomal transposition. We have followed the inheritance of these genes in a cross between two clones of P. falciparum. Examination of progeny shows that one gene, encoding the protein HRP-II, behaves as expected and may be inherited from either parent. The other gene, encoding HRP-III, has been found to derive from one parent in all progeny examined. We conclude the linkage group marked by HRP-III is favored strongly in the cross. This linkage group spans a region at one end of chromosome 13. Growth studies suggest the favored inheritance is explained by rapid expansion of progeny possessing the HRP-III marker relative to slower growth of progeny without it.

Chromosome Mapping↗
PubMed1987

The cDNA-deduced primary structure of human sex hormone-binding globulin and location of its steroid-binding domain.

We have sequenced a cDNA for sex hormone-binding globulin (SHBG) isolated from a phage lambda gt11 human liver cDNA library. The library was screened with a radiolabeled rat androgen-binding protein (ABP) cDNA, and the abundance of SHBG cDNAs was 1 in 750,000 plaques examined. The largest human SHBG cDNA (1194 base-pairs) contained a reading frame for 381 amino acids. This comprised 8 amino acids of a signal peptide followed by 373 residues starting with the known NH2-terminal sequence of human SHBG, and ending with a termination codon. The predicted polypeptide Mr of SHBG is 40,509, and sites of attachment of one O-linked (residue 7) and two N-linked oligosaccharide (residues 351 and 367) chains were identified. Purified SHBG was photoaffinity-labeled with delta 6-[3H]testosterone and cleaved with trypsin. The labeled tryptic fragment was isolated by reverse-phase HPLC, and its NH2-terminal sequence was determined. The results suggest that a portion of the steroid-binding domain of SHBG is located between residue 296 and the 35 predominantly hydrophilic residues at the C-terminus of the protein.

Amino Acid Sequence↗
PubMed1987

Methylation of the alpha-fetoprotein gene in isogenic rat hepatoma and liver cell lines.

We have found that DNA methylation is inversely correlated with alpha-fetoprotein (AFP) gene expression in a series of isogenic rat hepatoma cell lines. The 5' end of the gene is extensively demethylated in AFP-producing cells and is highly methylated in cell lines which do not produce AFP. Glucocorticoid affects markedly the synthesis of AFP in the hepatoma cells. However, methylation patterns of cell lines which were treated with dexamethasone were not different from those of control cells, indicating that glucocorticoid action on AFP gene expression does not alter DNA methylation in this region of the gene.

Animals↗