Cell death by apoptosis is indispensable for proper development and tissue homeostasis in all multicellular organisms, and its deregulation plays a key role in cancer and many other diseases. A crucial event in apoptosis is the formation of protein-permeable pores in the outer mitochondrial membrane that release cytochrome c and other apoptosis-promoting factors into the cytosol. Research effor...

In a genetic screen for nucleoporin-interacting components, a novel nuclear pore protein Nup84p, which exhibits homology to mammalian Nup107p, was isolated. Nup84p forms a complex with five proteins, of which Nup120p, Nup85p, Sec13p, and a Sec13p homolog were identified. Upon isolation of Sec13p-ProtA, nucleoporins were still associated, but the major copurifying band was a 150 kDa protein, sho...

The inner pore of voltage-gated Ca2+ channels (VGCCs) is functionally important, but little is known about the architecture of this region. In K+ channels, this part of the pore is formed by the S6/M2 transmembrane segments from four symmetrically arranged subunits. The Ca2+ channel pore, however, is formed by four asymmetric domains of the same (alpha1) subunit. Here we investigated the archit...

Complexities in pore scale structure, rock-fluid and fluid-fluid interactions have a profound effect on the estimation of reserves, reservoir recovery and productivity in reservoir core material. These complexities determine the pore scale distribution of fluids within the pore space, which, in turn, determine the petrophysical response of the rock. A very important example is the estimation of...

All molecular traffic between nucleus and cytoplasm occurs via the nuclear pore complex (NPC) within the nuclear envelope. In this study we analyzed the interactions of the nuclear transport receptors kapalpha2, kapbeta1, kapbeta1DeltaN44, and kapbeta2, and the model transport substrate, BSA-NLS, with NPCs to determine binding sites and kinetics using single-molecule microscopy in living cells....

Several methodologies published in the literature can be used to construct realistic pore networks for simple rocks, whereas in complex pore geometry formations, as formed in tight reservoirs, such a construction still remains a challenge. A basic understanding of pore structure and topology is essential to overcome the challenges associated with the pore scale modeling of tight porous media. A...

A protein that imitates the sequence of a highly conserved segment predicted to line the pore of dihydropyridine-sensitive L-type calcium channels was designed and synthesized. Single-channel conductance properties were studied in planar lipid bilayers. The synthetic protein emulates the ionic conductance, ionic selectivity, and pharmacological properties of the authentic calcium channel, inclu...

In this article, we are interested in the existence of positive solutions for the following Kirchhoff type system  −M1 (∫ Ω |x| −ap|∇u|p dx ) div(|x|−ap|∇u|p−2∇u) = λ|x|−(a+1)p+c1 (f(v)− 1 uα ) in Ω, −M2 (∫ Ω |x| −bq |∇v|q dx ) div(|x|−bq |∇v|q−2∇v) = λ|x|−(b+1)q+c2 (g(u)− 1 vβ ) in Ω, u = v = 0 on ∂Ω, (1) where Ω is a bounded smooth domain of R with 0 ∈ Ω, 1 < p, q < N , 0 ≤ a, b < N−p p , c...

X-ray micro-computer aided tomography (μ-CT), together with optical microscopy and imaging, have been applied to the study of six moldavite samples. These techniques enabled a complete characterization to be made of the textural features of both Muong Nong-type and common splashform moldavites. A detailed study of the size and distribution of pores or bubbles confirmed the marked variability in...

Type III secretion systems (T3SS) are nano-syringes used by a wide range of Gram-negative pathogens to promote infection by directly injecting effector proteins into targeted host cells. Translocation of effectors is triggered by host-cell contact and requires assembly of a pore in the host-cell plasma membrane, which consists of two translocator proteins. Our understanding of the translocation...