Crystallization of importin alpha, the nuclear-import receptor

Crystals of recombinant importin alpha, the nuclear-import receptor, have been obtained at two different pH conditions by vapour diffusion using sodium citrate as precipitant and dithiothreitol as an additive. At pH 4-5, the crystals have the symmetry of the trigonal space group P3(1)21 or P3(2)21 (a = b = 78.0, c = 255.8 Angstrom, gamma = 120 degrees); at pH 6-7, the crystals have the symmetry of the orthorhombic space group P2(1)2(1)2(1) (a = 78.5, b = 89.7, c = 100.5 Angstrom). In both cases, there is probably one molecule of importin ct in the asymmetric unit. At least one of the crystal forms diffracts to a resolution higher than 3 Angstrom using the laboratory X-ray source; the crystals are suitable for crystal structure determination.

Australian import managers' purchasing decision behaviour: An empirical study

Reports a pilot study of the relative importance of import decision variables as rated by Australian managers. A systematic sample qi 104 Australian managers representing different companies participated in the study. Australian importers rated product quality as the most important variable when importing products from overseas followed by long-term suppliers' dependability, product style/feature, price, and timely delivery. Australian managers who import consumer products find the domestic import duties and tariffs to be more important than did those who import industrial products. Larger volume importers regard the product brand name reputation to be more important than did those who import smaller volumes.

Import substitution and economic growth

Despite Latin America`s dismal performance between the 1950s and 1980s, the region experienced strong capital deepening. We suggest that these facts can be explained as a consequence of the restrictive trade regime adopted at that time. Our framework is based on a dynamic Heckscher-Ohlin model, with scale economies in the capital-intensive sector. Initially, the economy is open and produces only the labor-intensive good. The trade regime is modeled as a move to a closed economy. The model produces results consistent with the Latin American experience. Specifically, a Sufficiently small Country experiences no long-run income growth, but an increase in capital. (C) 2009 Elsevier B.V. All rights reserved.

Biophysical characterization of interactions involving importin-alpha during nuclear import

Proteins containing the classical nuclear localization sequences (NLSs) are imported into the nucleus by the importin-alpha/beta heterodimer. Importin-alpha contains the NLS binding site, whereas importin-beta mediates the translocation through the nuclear pore. We characterized the interactions involving importin-alpha during nuclear import using a combination of biophysical techniques (biosensor, crystallography, sedimentation equilibrium, electrophoresis, and circular dichroism). Importin-alpha is shown to exist in a monomeric autoinhibited state (association with NLSs undetectable by biosensor). Association with importin-beta (stoichiometry, 1:1; K-D = 1.1 x 10(-8) m) increases the affinity for NLSs; the importin-alpha/beta complex binds representative monopartite NLS (simian virus 40 large T-antigen) and bipartite NLS (nucleoplasmin) with affinities (K-D = 3.5 x 10(-8) m and 4.8 x 10(-8) m, respectively) comparable with those of a truncated importin-alpha lacking the autoinhibitory domain (T-antigen NLS, K-D = 1.7 x 10(-8) m; nucleoplasmin NLS, K-D = 1.4 x 10(-8) m). The autoinhibitory domain (as a separate peptide) binds the truncated importin-alpha, and the crystal structure of the complex resembles the structure of full-length importin-alpha. Our results support the model of regulation of nuclear import mediated by the intrasteric autoregulatory sequence of importin-alpha and provide a quantitative description of the binding and regulatory steps during nuclear import.

Produtividade e sa??de financeira: a import??ncia da venda de servi??os pela Base Naval de Natal para clientes extra: Marinha

A Marinha, com sua vis??o para o futuro e preocupada com a dificuldade de mensura????o dos custos de suas organiza????es industriais e prestadoras de servi??os, instituiu, a partir de 1994, o sistema de Organiza????es Militares Prestadoras de Servi??os (OMPS). Nesse contexto, a base Naval de Natal (BNN) precisou encontrar propostas que a mantivesse superavit??ria. Para tal, tornou-se necess??rio o engajamento de todos os n??veis da OM para, dentro de uma vis??o sist??mica de mensura????o existente, atingir um desempenho global satisfat??rio. Ap??s a implanta????o da iniciativa, alcan??ou-se o aumento substancial do faturamento, com rela????o aos clientes extra-Marinha, a redu????o dos prazos de prontifica????o dos servi??os prestados, sem queda na qualidade e com a constante preocupa????o de se verificar o n??vel de satisfa????o do cliente; o incremento da terceiriza????o consciente; o surgimento de parcerias com a iniciativa privada que geraram a otimiza????o da capacidade instalada em algumas oficinas; maior agilidade no processo de obten????o, devido a uma melhor coordena????o entre as ??reas industrial e de log??stica; e a possibilidade de investimentos na ??rea industrial e nas condi????es de trabalho,em decorr??ncia do aumento da produtividade

Caf?? com debate: a gest??o de processos na administra????o p??blica federal: import??ncia, avan??os e desafios

A import??ncia, os avan??os e os desafios da gest??o de processos na administra????o p??blica federal foram abordados em mais uma edi????o do Caf?? com Debate, no ??ltimo dia 23 de outubro. O encontro, que reuniu cerca de 120 pessoas de diversos ??rg??os, permitiu a troca de experi??ncias sobre modelos que proporcionam a diminui????o dos tempos de ciclos internos, a melhoria da qualidade e da efici??ncia dos ??rg??os, bem como a redu????o de custos

M??dulo 1 - a import??ncia e a necessidade da lei de licita????es: curso legisla????o aplicada ?? log??stica de suprimentos lei 8.666/93, preg??o e registro de pre??os

Este documento trata de: aspectos conceituais da lei: finalidade, import??ncia e hierarquia da lei.; no????es gerais da lei de licita????es - Lei n?? 8.666/93; tipos de licita????o:menor pre??o, melhor t??cnica, t??cnica e pre??o e maior lance ou oferta; modalidades de licita????o: concorr??ncia, tomada de pre??os, convite, concurso e leil??o; exce????es ?? obrigatoriedade de licita????o: dispensa e inexigibilidade; regime de execu????o indireta; comiss??o de licita????o; etapas do processo licitat??rio: edital, procedimentos/documentos do certame, registro cadastral, habilita????o dos interessados, julgamento e encerramento; preg??o; registro de pre??os

Painel 3 - A Import??ncia da Integra????o das Estat??sticas Oficiais

Painel 3 - Monitoramento da A????o Governamental e a Import??ncia das Estat??sticas Oficiais; Palestra 1 - ???Monitoramento e Avalia????o do Desenvolvimento Humano: a insensibilidade do ??ndice de Desenvolvimento Humano ??s pol??ticas de desenvolvimento social???, apresentada por Paulo de Martino Jannuzzi; Palestra 2 - ???Comit?? de Estat??sticas Sociais contribui para o fortalecimento e integra????o das estat??sticas oficiais brasileiras???, apresentada por Jailson Mangueira Assis

A sociologia de Max Weber: sua import??ncia para a teoria e a pr??tica da administra????o

A tradu????o integral da obra de Max Weber ??? Wirtschaft und Gesellschaft ??? empreendida pela editora mexicana ??? Fondo de Cultura Econ??mica, sob a esclarecida dire????o de Jos?? Medina Echavarr??a, ?? um acontecimento a cuja magnitude esta Revista n??o pode permanecer indiferente. ?? esta a primeira vez que a referida obra aparece em l??ngua diferente da original, pois a anunciada tradu????o do seu primeiro volume, realizada por Parsons-Henderson, n??o foi editada at?? o presente e, ao que me consta, circula mimeografada, em restritos centros de estudo dos Estados Unidos. Apesar de inacabada e fragment??ria e de ser um livro p??stumo, publicado gra??as ?? dedica????o e compet??ncia de Marianna Weber, esposa do autor, Economia e Sociedade ?? a obra n??o s?? onde se re??nem os temas centrais de Max Weber, como tamb??m onde ele exp??e o seu sistema de sociologia.

Importance of sequences adjacent to the terminal tripeptide in the import of a peroxisomal Candida tropicalis protein in plant peroxisomes.

The peroxisome targeting signal (PTS) required for import of the rat acyl-CoA oxidase (AOX; EC 1.3.3.6) and the Candida tropicalis multifunctional protein (MFP) in plant peroxisomes was assessed in transgenic Arabidopsis thaliana (L.) Heynh. The native rat AOX accumulated in peroxisomes in A. thaliana cotyledons and targeting was dependent on the presence of the C-terminal tripeptide S-K-L. In contrast, the native C. tropicalis MFP, containing the consensus PTS sequence A-K-I was not targeted to plant peroxisomes. Modification of the carboxy terminus to the S-K-L tripeptide also failed to deliver the MFP to peroxisomes while addition of the last 34 amino acids of the Brassica napus isocitrate lyase, containing the terminal tripeptide S-R-M, enabled import of the fusion protein into peroxisomes. These results underline the influence of the amino acids adjacent to the terminal tripeptide of the C. tropicalis MFP on peroxisomal targeting, even in the context of a protein having a consensus PTS sequence S-K-L.

Transportin regulates nuclear import of CD44.

CD44 is a facultative cell surface proteoglycan that serves as the principal cell surface receptor for hyaluronan (HA). Studies have shown that in addition to participating in numerous signaling pathways, CD44 becomes internalized upon engagement by ligand and that a portion of its intracellular domain can translocate to the nucleus where it is believed to play a functional role in cell proliferation and survival. However, the mechanisms whereby fragments of CD44 enter the nucleus have not been elucidated. Here we show that CD44 interacts with two import receptors of the importin β superfamily, importin β itself and transportin. Inhibition of importin β-dependent transport failed to block CD44 accumulation in the nucleus. By contrast, inhibition of the transportin-dependent pathway abrogated CD44 import. Mutagenesis of the intracellular domain of CD44 revealed that the 20 membrane-proximal residues contain sequences required for transportin-mediated nuclear transport. Our observations provide evidence that CD44 interacts with importin family members and identify the transportin-dependent pathway as the mechanism whereby full-length CD44 enters the nucleus.

FHY1 mediates nuclear import of the light-activated phytochrome A photoreceptor.

The phytochrome (phy) family of photoreceptors is of crucial importance throughout the life cycle of higher plants. Light-induced nuclear import is required for most phytochrome responses. Nuclear accumulation of phyA is dependent on two related proteins called FHY1 (Far-red elongated HYpocotyl 1) and FHL (FHY1 Like), with FHY1 playing the predominant function. The transcription of FHY1 and FHL are controlled by FHY3 (Far-red elongated HYpocotyl 3) and FAR1 (FAr-red impaired Response 1), a related pair of transcription factors, which thus indirectly control phyA nuclear accumulation. FHY1 and FHL preferentially interact with the light-activated form of phyA, but the mechanism by which they enable photoreceptor accumulation in the nucleus remains unsolved. Sequence comparison of numerous FHY1-related proteins indicates that only the NLS located at the N-terminus and the phyA-interaction domain located at the C-terminus are conserved. We demonstrate that these two parts of FHY1 are sufficient for FHY1 function. phyA nuclear accumulation is inhibited in the presence of high levels of FHY1 variants unable to enter the nucleus. Furthermore, nuclear accumulation of phyA becomes light- and FHY1-independent when an NLS sequence is fused to phyA, strongly suggesting that FHY1 mediates nuclear import of light-activated phyA. In accordance with this idea, FHY1 and FHY3 become functionally dispensable in seedlings expressing a constitutively nuclear version of phyA. Our data suggest that the mechanism uncovered in Arabidopsis is conserved in higher plants. Moreover, this mechanism allows us to propose a model explaining why phyA needs a specific nuclear import pathway.