Dual roles for DNA sequence identity and the mismatch repair system in the regulation of mitotic crossing-over in yeast

Sequence divergence acts as a potent barrier to homologous recombination; much of this barrier derives from an antirecombination activity exerted by mismatch repair proteins. An inverted repeat assay system with recombination substrates ranging in identity from 74% to 100% has been used to define the relationship between sequence divergence and the rate of mitotic crossing-over in yeast. To elucidate the role of the mismatch repair machinery in regulating recombination between mismatched substrates, we performed experiments in both wild-type and mismatch repair defective strains. We find that a single mismatch is sufficient to inhibit recombination between otherwise identical sequences, and that this inhibition is dependent on the mismatch repair system. Additional mismatches have a cumulative negative effect on the recombination rate. With sequence divergence of up to approximately 10%, the inhibitory effect of mismatches results mainly from antirecombination activity of the mismatch repair system. With greater levels of divergence, recombination is inefficient even in the absence of mismatch repair activity. In both wild-type and mismatch repair defective strains, an approximate log-linear relationship is observed between the recombination rate and the level of sequence divergence.

Manipulating the genetic identity and biochemical surface properties of individual cells with electric-field-induced fusion

A method for cell–cell and cell–liposome fusion at the single-cell level is described. Individual cells or liposomes were first selected and manipulated either by optical trapping or by adhesion to a micromanipulator-controlled ultramicroelectrode. Spatially selective fusion of the cell–cell or cell–liposome pair was achieved by the application of a highly focused electric field through a pair of 5-μm o.d. carbon-fiber ultramicroelectrodes. The ability to fuse together single cells opens new possibilities in the manipulation of the genetic and cellular makeup of individual cells in a controlled manner. In the study of cellular networks, for example, the alteration of the biochemical identity of a selected cell can have a profound effect on the behavior of the entire network. Fusion of a single liposome with a target cell allows the introduction of the liposomal content into the cell interior as well as the addition of lipids and membrane proteins onto the cell surface. This cell–liposome fusion represents an approach to the manipulation of the cytoplasmic contents and surface properties of single cells. As an example, we have introduced a membrane protein (γ-glutamyltransferase) reconstituted in liposomes into the cell plasma membrane.

Assessment of clone identity and sequence fidelity for 1189 IMAGE cDNA clones

This report documents the error rate in a commercially distributed subset of the IMAGE Consortium mouse cDNA clone collection. After isolation of plasmid DNA from 1189 bacterial stock cultures, only 62.2% were uncontaminated and contained cDNA inserts that had significant sequence identity to published data for the ordered clones. An agarose gel electrophoresis pre-screening strategy identified 361 stock cultures that appeared to contain two or more plasmid species. Isolation of individual colonies from these stocks demonstrated that 7.1% of the original 1189 stocks contained both a correct and an incorrect plasmid. 5.9% of the original 1189 stocks contained multiple, distinct, incorrect plasmids, indicating the likelihood of multiple contaminating events. While only 739 of the stocks purchased contained the desired cDNA clone, agarose gel pre-screening, colony isolation and similarity searching of dbEST allowed for the identification of an additional 420 clones that would have otherwise been discarded. Considering the high error rate in this subset of the IMAGE cDNA clone set, the use of sequence verified clones for cDNA microarray construction is warranted. When this is not possible, pre-screening non-sequence verified clones with agarose gel electrophoresis provides an inexpensive and efficient method to eliminate contaminated clones from the probe set.

Molecular identity and cellular distribution of advanced glycation endproduct receptors: relationship of p60 to OST-48 and p90 to 80K-H membrane proteins.

Advanced glycation endproducts (AGEs) are derivatives of nonenzymatic reactions between sugars and protein or lipids, and together with AGE-specific receptors are involved in numerous pathogenic processes associated with aging and hyperglycemia. Two of the known AGE-binding proteins isolated from rat liver membranes, p60 and p90, have been partially sequenced. We now report that the N-terminal sequence of p60 exhibits 95% identity to OST-48, a 48-kDa member of the oligosaccharyltransferase complex found in microsomal membranes, while sequence analysis of p90 revealed 73% and 85% identity to the N-terminal and internal sequences, respectively, of human 80K-H, a 80- to 87-kDa protein substrate for protein kinase C. AGE-ligand and Western analyses of purified oligosaccharyltransferase complex, enriched rough endoplasmic reticulum, smooth endoplasmic reticulum, and plasma membranes from rat liver or RAW 264.7 macrophages yielded a single protein of approximately 50 kDa recognized by both anti-p60 and anti-OST-48 antibodies, and also exhibited AGE-specific binding. Immunoprecipitated OST-48 from rat rough endoplasmic reticulum fractions exhibited both AGE binding and immunoreactivity to an anti-p60 antibody. Immune IgG raised to recombinant OST-48 and 80K-H inhibited binding of AGE-bovine serum albumin to cell membranes in a dose-dependent manner. Immunostaining and flow cytometry demonstrated the surface expression of OST-48 and 80K-H on numerous cell types and tissues, including mononuclear, endothelial, renal, and brain neuronal and glial cells. We conclude that the AGE receptor components p60 and p90 are identical to OST-48, and 80K-H, respectively, and that they together contribute to the processing of AGEs from extra- and intracellular compartments and in the cellular responses associated with these pathogenic substances.

Everyday Indivisibility: How Exclusive Religious Practices Explain Variation in Subnational Violence Outcomes

This project explores the puzzle of religious violence variation. Religious actors initiate conflict at a higher rate than their secular counterparts, last longer, are more deadly, and are less prone to negotiated termination. Yet the legacy of religious peacemakers on the reduction of violence is undeniable. Under what conditions does religion contribute to escalated violence and under what conditions does it contribute to peace? I argue that more intense everyday practices of group members, or high levels of orthopraxy, create dispositional indivisibilities that make violence a natural alternative to bargaining. Subnational armed groups with members whose practices are exclusive and isolating bind together through ritual practice, limit the acceptable decisions of leaders, and have prolonged timeframes, all of which result in higher levels of intensity, intransigence and resolve during violent conflict. The theory challenges both instrumentalist and constructivist understandings of social identity and violence. To support this argument, I construct an original cross-national data-set that employs ethnographic data on micro-level religious practices for 724 subnational armed groups in both civil wars and terror campaigns. Using this data, I build an explanatory “religious practice index” for each observation and examine its relationship with conflict outcomes. Findings suggest that exclusive practice groups fight significantly longer with more intensity and negotiate less. I also apply the practice model to qualitative cases. Fieldwork in the West Bank and Sierra Leone reveals that groups with more exclusive religious practicing membership are principle contributors to violence, whereas those with inclusive practices can contribute to peace. The project concludes with a discussion about several avenues for future research and identifies the practical policy applications to better identify and combat religious extremism.

Tracing an American Yoga: Identity and Cross-Cultural Transaction

This dissertation looks at the creative identity of an American yoga, both rooted in its Indic origins and radically transformed in its U.S. manifestations. It traces the broad historical transactions of yoga in terms of East and West, Secular and Religious, authenticity and idealized conception, as well as provides a critical historical genealogy of Anusara and Sridaiva yoga. Furthermore, the project relates yoga to the identity, power, and knowledge dynamics of pre-modern, modern, and postmodern histories and interpretations of yoga and Tantra, multiple theoretical discourses, and the embodied practices of individuals within Indian and American contexts. I argue that there is a unique and polysemous yogic identity in America, and that this identity has developed from a messy process of transaction between Indian and Western modes of being and knowing. Furthermore, the current Americanized culture of yoga brings along with it narratives of specific value. American yoga displays a particularly consumptive quality of yogic lifestyle that reflects a cultural atmosphere of reinvention and a merging of profit and personal purpose. American yoga’s identity today is entrepreneurial, branded, business oriented, and marketed for consumption. This dissertation shows how the American yogic identity is in flux, continuously fracturing and multiplying into various and novel understandings that relate to yoga’s past and to the market value for today’s American consumer. It examines the moving nature of yoga in the American landscape as what Jared Farmer calls a “center of creativity” and as a display of excess and choice. The discussion of yoga is further located in John Friend’s styles of yoga and/or lifestyle practices, Anusara and Sridaiva, as they both redefine and further remove yoga from established Indian markers of identity. My locations as American yogi, as comparativist, as ethnographer, and as a Bachelor of Science in Advertising and Marketing also situate this analysis.

A two-step mechanism for epigenetic specification of centromere identity and function

The basic determinant of chromosome inheritance, the centromere, is specified in many eukaryotes by an epigenetic mark. Using gene targeting in human cells and fission yeast, chromatin containing the centromere-specific histone H3 variant CENP-A is demonstrated to be the epigenetic mark that acts through a two-step mechanism to identify, maintain and propagate centromere function indefinitely. Initially, centromere position is replicated and maintained by chromatin assembled with the centromere-targeting domain (CATD) of CENP-A substituted into H3. Subsequently, nucleation of kinetochore assembly onto CATD-containing chromatin is shown to require either the amino- or carboxy-terminal tail of CENP-A for recruitment of inner kinetochore proteins, including stabilizing CENP-B binding to human centromeres or direct recruitment of CENP-C, respectively.

The youth gangs, drugs, and violence connection /

"January 1999."

Intimidation and violence : racial and religious bigotry in America /

"January 1983."

An essay on the identity and general resurrection of the human body : in which the evidences in favour of these important subjects are considered, in relation both to philosophy and Scripture /

Mode of access: Internet.

The analogy of religion, natural and revealed, to the constitution and course of nature : to which are added, two brief dissertations: on personal identity, and on the nature of virtue; and fifteen sermons /

Includes bibliographical references and index.