Bioluminescence imaging of dual gene expression at the single-cell level

Bioluminescence imaging reveals the long-term dynamics of individual gene expression in a single cell. However, methods for simultaneously imaging multiple gene expression patterns have been unknown to date. Here, we constructed a dual-path optical luminescence imaging system using a two-color reporter system and could simultaneously track two gene expression patterns for several days in a single cell

In Situ Observation on Hierarchical Actin Bundle Networks(Poster session 1, New Frontiers in Colloidal Physics : A Bridge between Micro- and Macroscopic Concepts in Soft Matter)

この論文は国立情報学研究所の電子図書館事業により電子化されました。アメーバ運動は、生体内の細胞骨格タンパク質であるアクチンがアクチン結合タンパク質を介して形成するバンドル、二次元ネットワーク、三次元ゲル構造の構築と消滅の制御によって生み出されている。本研究では、アクチン結合タンパク質のモデルとしてポリカチオンを用い、フィラメントアクチンとポリカチオンが形成する複合体構造を中性子超小角散乱法を用いて観察した。その結果、ポリカチオン濃度の増大によるバンドル内のフィラメント密度の増大、および、塩濃度の増加によるバンドル構造の消滅を明らかにした。Actin is one of the most abundant cytoskeleton proteins in eucaryotic cell. They play a crucial role in cell motility by polymerizing monomeric globular G-actin into polymeric filamentous actin (F-actin). With actin-binding proteins (ABPs), they form higher order structures such as linear bundles, two-dimensional networks and three-dimensional gels. It has been considered that these structures are controlled by ABPs. However recent study have shown that the only one kind of artificial cationic polymer can form variety of structures depending its concentration and salt concentration. This system is a good model to elucidate the mechanism of regulation of actin and ABPs complex structure. Based on these backgrounds, we have investigated the effects of salt concentration on the stability and structure of actin-polycation complexes by using small angle neutron scattering (SANS) technique

Large-area niobium disulfide thin films as transparent electrodes for devices based on two-dimensional materials

Direct contacts of a metal with atomically thin two-dimensional (2D) transition metal dichalcogenide (TMDC) semiconductors have been found to suppress device performance by producing a high contact resistance. NbS2 is a 2D TMDC and a conductor. It is expected to form ohmic contacts with 2D semiconductors because of its high work function and the van der Waals interface it forms with the semiconductor, with such an interface resulting in weak Fermi level pinning. Despite the usefulness of NbS2 as an electrode, previous synthesis methods could not control the thickness, uniformity, and shape of the NbS2 film and hence could not find practical applications in electronics. Here, we report a patternable method for carrying out the synthesis of NbS2 films in which the number of NbS2 layers formed over a large area was successfully controlled, which is necessary for the production of customized electrodes. The synthesized NbS2 films were shown to be highly transparent and uniform in thickness and conductivity over the large area. Furthermore, the synthesized NbS2 showed half the contact resistance than did the molybdenum metal in MoS2 field effect transistors (FETs) on a large transparent quartz substrate. The MoS2 device with NbS2 showed an electron mobility as high as 12.7 cm(2) V-1 s(-1), which was three times higher than that found for the corresponding molybdenum-contacted MoS2 device. This result showed the high potential of the NbS2 thin film as a transparent electrode for 2D transition metal dichalcogenide (TMDC) semiconductors with low contact resistance