Cooperation between primary cilia signaling and integrin receptor extracellular matrix engagement regulates progenitor proliferation and neuronal differentiation in the developing cerebellum.

Neural progenitors and their neuronal progeny are bathed in extrinsic signals that impact critical decisions like the mode of cell division, how long they should reside in specific neuronal laminae, when to differentiate, and the timing of migratory decisions. Chief among these signals are secreted morphogens and extracellular matrix (ECM) molecules. Among the many cellular organelles and cell surface receptors that sense morphogen and ECM signals, the primary cilia and integrin receptors are some of the most important mediators of extracellular signals.

Mechanism of Action of Peptides That Cause the pH-Triggered Macromolecular Poration of Lipid Bilayers.

Using synthetic molecular evolution, we previously discovered a family of peptides that cause macromolecular poration in synthetic membranes at low peptide concentration in a way that is triggered by acidic pH. To understand the mechanism of action of these "pHD peptides", here we systematically explored structure-function relationships through measurements of the effect of pH and peptide concentration on membrane binding, peptide structure, and the formation of macromolecular-sized pores in membranes. Both AFM and functional assays demonstrate the peptide-induced appearance of large pores in bilayers.

High-Resolution AFM-Based Force Spectroscopy.

Atomic force microscopy (AFM)-based force spectroscopy is a powerful technique which has seen significant enhancements in both force and time resolution in recent years. This chapter details two AFM cantilever modification procedures that yield high force precision over different temporal bandwidths. Specifically, it explains a fairly straightforward method to achieve sub-pN force precision and stability at low frequencies (<50 Hz) by removing the metal coatings from a commercially available cantilever.

Conformations and Dynamic Transitions of a Melittin Derivative That Forms Macromolecule-Sized Pores in Lipid Bilayers.

Systematically evolved from the primary active component of bee venom, MelP5 is a lipophilic peptide with important physical properties that differ from wild-type melittin, including the ability to create large equilibrium pores in lipid bilayers at low peptide to lipid ratios. Self-assembly into stable membrane spanning pores makes MelP5 a promising candidate for future applications in the pharmaceutical arena. Despite significant interest, little is known about the mechanism by which MelP5 remodels the lipid bilayer upon binding.

Potent Macromolecule-Sized Poration of Lipid Bilayers by the Macrolittins, A Synthetically Evolved Family of Pore-Forming Peptides.

Pore-forming peptides with novel functions have potential utility in many biotechnological applications. However, the sequence-structure-function relationships of pore forming peptides are not understood well enough to empower rational design. Therefore, in this work, we used synthetic molecular evolution to identify a novel family of peptides that are highly potent and cause macromolecular poration in synthetic lipid vesicles at low peptide concentration and at neutral pH.

Reported serial positions of true and illusory memories in the Deese/Roediger/McDermott paradigm.

One of the easiest ways to induce illusory memories in the laboratory is to use the Deese-Roediger-McDermott (DRM) word-list paradigm. Researchers have used this paradigm not only to study people's memories of stimuli that were not actually presented, but also to study the phenomenological qualities of these illusions. In four experiments, the current investigation explored a phenomenological quality of illusory memories that has received almost no attention, specifically, temporality.