Desensitization, internalization, and signaling functions of beta-arrestins demonstrated by RNA interference.

Beta-arrestins bind to activated G protein-coupled receptor kinase-phosphorylated receptors, which leads to their desensitization with respect to G proteins, internalization via clathrin-coated pits, and signaling via a growing list of "scaffolded" pathways. To facilitate the discovery of novel adaptor and signaling roles of beta-arrestins, we have developed and validated a generally applicable interfering RNA approach for selectively suppressing beta-arrestins 1 or 2 expression by up to 95%. Beta-arrestin depletion in HEK293 cells leads to enhanced cAMP generation in response to beta(2)-adrenergic receptor stimulation, markedly reduced beta(2)-adrenergic receptor and angiotensin II receptor internalization and impaired activation of the MAP kinases ERK 1 and 2 by angiotensin II. This approach should allow discovery of novel signaling and regulatory roles for the beta-arrestins in many seven-membrane-spanning receptor systems.

Mix it and fix it: functions of composite olfactory signals in ring-tailed lemurs.

Animals communicating via scent often deposit composite signals that incorporate odorants from multiple sources; however, the function of mixing chemical signals remains understudied. We tested both a 'multiple-messages' and a 'fixative' hypothesis of composite olfactory signalling, which, respectively, posit that mixing scents functions to increase information content or prolong signal longevity. Our subjects-adult, male ring-tailed lemurs (Lemur catta)-have a complex scent-marking repertoire, involving volatile antebrachial (A) secretions, deposited pure or after being mixed with a squalene-rich paste exuded from brachial (B) glands. Using behavioural bioassays, we examined recipient responses to odorants collected from conspecific strangers. We concurrently presented pure A, pure B and mixed A + B secretions, in fresh or decayed conditions. Lemurs preferentially responded to mixed over pure secretions, their interest increasing and shifting over time, from sniffing and countermarking fresh mixtures, to licking and countermarking decayed mixtures. Substituting synthetic squalene (S)-a well-known fixative-for B secretions did not replicate prior results: B secretions, which contain additional chemicals that probably encode salient information, were preferred over pure S. Whereas support for the 'multiple-messages' hypothesis underscores the unique contribution from each of an animal's various secretions, support for the 'fixative' hypothesis highlights the synergistic benefits of composite signals.

A Prescription for the Future of Religious Studies: Second-Order Tradition and the Spirit of Modern Science

An examination of the efficacy of religious studies scholarship through a Kuhnian lens.

Knowing The Way: Scriptural Imagination and the Acts of the Apostles

In this dissertation, I offer a pedagogical proposal for learning the Christian Scriptures guided by respect for the nature of the reader and the integrity of the biblical text. Christian educators have profitably developed recent theoretical interest in the body’s role in human meaning with regard to worship and praxis methodologies, but the implications of this research for communal study of the biblical text merit further development. I make the case for adopting scriptural imagination as the goal of pedagogically constructed encounters with the Christian Scriptures. The argument proceeds through a series of questions addressing both sides of the text/reader encounter.

Chapter one considers the question “what is the nature of the reader and, subsequently, the shape of the reader’s ways of knowing?” This investigation into recent literature on the body’s involvement in human knowing includes related epistemological shifts with Christian education. On the basis of this survey, imagination emerges as a compelling designator of an incorporative, constructive creaturely capacity that gives rise to a way of being in the world. Teachers of Scripture who intend to participate in Christian formation should account for the imagination’s centrality for all knowing. After briefly situating this proposal within a theological account of creatureliness, I make the initial case for Scriptural imagination as a pedagogical aim.

Imagination as creaturely capacity addresses the first guiding value, but does this proposal also respect the integrity and nature of the biblical text, and specifically of biblical narratives? In response, in chapter two I take up the Acts of the Apostles as a potential test case and exemplar for the dynamics pertinent to the formation of imagination. Drawing on secondary literature on the genre and literary features of Acts, I conclude that Acts coheres with this project’s explicit interest in imagination as a central component of the process of Christian formation in relationship to the Scriptures.

Chapters three and four each take up a pericope from Acts to assess whether the theoretical perspectives developed in prior chapters generate any interpretive payoff. In each of these chapters, a particular story within Acts functions as a test case for readings of biblical narratives guided by a concern for scriptural imagination. Each of these chapters begins with further theoretical development of some element of imaginal formation. Chapter three provides a theoretical account of practices as they relate to imagination, bringing that theory into conversation with Peter’s engagement in hospitality practices with Cornelius in Acts 10:1-11:18. Chapter four discusses the formative power of narratives, with implications for the analysis of Paul’s shipwreck in Acts 27:1-28:16.

In the final chapter, I offer a two-part constructive pedagogical proposal for reading scriptural narratives in Christian communities. First, I suggest adopting resonance above relevance as the goal of pedagogically constructed encounters with the Scriptures. Second, I offer three ways of reading with the body, including the physical, ecclesial, and social bodies that shape all learning. I conclude by identifying the importance of scriptural imagination for Christian formation and witness in the twenty-first century.