Technology development has always been one of the forces driving breakthroughs in biomedical research. Since the time of Thomas Morgan, Drosophilists have, step by step, developed powerful genetic tools for manipulati...Technology development has always been one of the forces driving breakthroughs in biomedical research. Since the time of Thomas Morgan, Drosophilists have, step by step, developed powerful genetic tools for manipulating and functionally dissecting the Drosophila genome, but room for improving these technologies and developing new techniques is still large, especially today as biologists start to study systematically the functional genomics of different model organisms, including humans, in a high-throughput manner. Here, we report, for the first time in Drosophila, a rapid, easy, and highly specific method for modifying the Drosophila genome at a very high efficiency by means of an improved transcription activator-like effector nuclease （TALEN） strategy. We took advantage of the very recently developed ＂unit assembly＂ strategy to assemble two pairs of specific TALENs designed to modify the yellow gene （on the sex chromosome） and a novel autosomal gene. The mRNAs of TALENs were subsequently injected into Drosophila embryos. From 31.2% of the injected Fo fertile flies, we detected inheritable modification involving the yellow gene. The entire process from construction of specific TALENs to detection of inheritable modifications can be accomplished within one month. The potential applications of this TALEN-mediated genome modification method in Drosophila are discussed.展开更多
A nanofabrication method for the production of ultra-dense planar metallic nanowire arrays scalable to wafer-size is presented. The method is based on an efficient template deposition process to grow diverse metallic ...A nanofabrication method for the production of ultra-dense planar metallic nanowire arrays scalable to wafer-size is presented. The method is based on an efficient template deposition process to grow diverse metallic nanowire arrays with extreme regularity in only two steps. First, Ⅲ-Ⅴ semiconductor substrates are irradiated by a low-energy ion beam at an elevated temperature, forming a highly ordered nanogroove pattern by a ＂reverse epitaxy＂ process due to self-assembly of surface vacancies. Second, diverse metallic nanowire arrays （Au, Fe, Ni, Co, FeAl alloy） are fabricated on these Ⅲ-Ⅴ templates by deposition at a glancing incidence angle. This method allows for the fabrication of metallic nanowire arrays with periodicities down to 45 nm scaled up to wafer-size fabrication. As typical noble and magnetic metals, the Au and Fe nanowire arrays produced here exhibited large anisotropic optical and magnetic properties, respectively. The excitation of localized surface plasmon resonances （LSPRs） of the Au nanowire arrays resulted in a high electric field enhancement, which was used to detect phthalocyanine （CoPc） in surface-enhanced Raman scattering （SERS）. Furthermore, the Fe nanowire arrays showed a very high in-plane magnetic anisotropy of approximately 412 mT, which may be the largest in-plane magnetic anisotropy field yet reported that is solely induced via shape anisotropy within the plane of a thin film.展开更多
基金supported by the grants from the 973 Program(Nos.2009CB918702 and 2012CB945101)the NSFC(Nos.31071087 and 31100889)+1 种基金W.-M.D.is supported by NIH grant R01GM072562National Science Foundation of USA(IOS-1052333)
文摘Technology development has always been one of the forces driving breakthroughs in biomedical research. Since the time of Thomas Morgan, Drosophilists have, step by step, developed powerful genetic tools for manipulating and functionally dissecting the Drosophila genome, but room for improving these technologies and developing new techniques is still large, especially today as biologists start to study systematically the functional genomics of different model organisms, including humans, in a high-throughput manner. Here, we report, for the first time in Drosophila, a rapid, easy, and highly specific method for modifying the Drosophila genome at a very high efficiency by means of an improved transcription activator-like effector nuclease （TALEN） strategy. We took advantage of the very recently developed ＂unit assembly＂ strategy to assemble two pairs of specific TALENs designed to modify the yellow gene （on the sex chromosome） and a novel autosomal gene. The mRNAs of TALENs were subsequently injected into Drosophila embryos. From 31.2% of the injected Fo fertile flies, we detected inheritable modification involving the yellow gene. The entire process from construction of specific TALENs to detection of inheritable modifications can be accomplished within one month. The potential applications of this TALEN-mediated genome modification method in Drosophila are discussed.
基金This work was supported by the National Natural Science Foundation of China （Nos. 11622545 and U1732268）, One Hundred Talent Program of CAS and the Deutsche Forschungsgemeinschaft （No. LE2443/5-1）.
文摘A nanofabrication method for the production of ultra-dense planar metallic nanowire arrays scalable to wafer-size is presented. The method is based on an efficient template deposition process to grow diverse metallic nanowire arrays with extreme regularity in only two steps. First, Ⅲ-Ⅴ semiconductor substrates are irradiated by a low-energy ion beam at an elevated temperature, forming a highly ordered nanogroove pattern by a ＂reverse epitaxy＂ process due to self-assembly of surface vacancies. Second, diverse metallic nanowire arrays （Au, Fe, Ni, Co, FeAl alloy） are fabricated on these Ⅲ-Ⅴ templates by deposition at a glancing incidence angle. This method allows for the fabrication of metallic nanowire arrays with periodicities down to 45 nm scaled up to wafer-size fabrication. As typical noble and magnetic metals, the Au and Fe nanowire arrays produced here exhibited large anisotropic optical and magnetic properties, respectively. The excitation of localized surface plasmon resonances （LSPRs） of the Au nanowire arrays resulted in a high electric field enhancement, which was used to detect phthalocyanine （CoPc） in surface-enhanced Raman scattering （SERS）. Furthermore, the Fe nanowire arrays showed a very high in-plane magnetic anisotropy of approximately 412 mT, which may be the largest in-plane magnetic anisotropy field yet reported that is solely induced via shape anisotropy within the plane of a thin film.
