Myb-binding Protein 1a is a Nucleocytoplasmic Shuttling Protein that Utilizes CRM1-dependent and Independent Nuclear Export Pathways

Myb-binding protein 1a (Mybbp1a) is a novel nuclear protein localized predominantly, but not exclusively, in nucleoli. Although initially isolated as a c-Myb interacting protein, Mybbp1a is expressed ubiquitously, associates with a number of different transcription factors, and may play a role in both RNA polymerase I- and II-mediated transcriptional regulation. However, its precise function remains unclear. In this study we show that Mybbp1a is a nucleocytoplasmic shuttling protein and investigate the mechanisms responsible for both nuclear import and export. The carboxyl terminus of Mybbp1a, which contains seven short basic amino acid repeat sequences, is responsible for both nuclear and nucleolar localization, and this activity can be transferred to a heterologous protein. Deletion mapping demonstrated that these repeat sequences appear to act incrementally, with successive deletions resulting in a corresponding increase in the proportion of protein localized in the cytoplasm. Glutathione S-transferase pulldown experiments showed that the nuclear receptor importin-alpha/beta mediates Mybbp1a nuclear import. Interspecies heterokaryons were used to demonstrate that Mybbp1a was capable of shuttling between the nucleus and the cytoplasm. Deletion analysis and in vivo export studies using a heterologous assay system identified several nuclear export sequences which facilitate Mybbp1a nuclear export of Mybbp1a by CRM1-dependent and -independent pathways. (C) 2003 Elsevier Science (USA). All rights reserved.

The shoot controls zeatin riboside export from pea roots. Evidence from the branching mutant rms4

The rms4 mutant of pea (Pisum sativum L.) was used in grafting studies and cytokinin analyses of the root xylem sap to provide evidence that, at least for pea, the shoot can modify the import of cytokinins from the root. The rms4 mutation, which confers a phenotype with increased branching in the shoot, causes a very substantial decrease (down to 40-fold less) in the concentration of zeatin riboside (ZR) in the xylem sap of the roots. Results from grafts between wild-type (WT) and rms4 plants indicate that the concentration of cytokinins in the xylem sap of the roots is determined almost entirely by the genotype of the shoot. WT scions normalize the cytokinin concentration in the sap of rms4 mutant roots, whereas mutant scions cause WT roots to behave like those of self-grafted mutant plants. The mechanism whereby rms4 shoots of pea cause a down-regulation in the export of cytokinins from the roots is unknown at this time. However, our data provide evidence that the shoot transmits a signal to the roots and thereby controls processes involved in the regulation of cytokinin biosynthesis in the root.

Volunteerism and government policy in infant welfare in Queensland, Australia, 1931-1961: Working round the ban

Whereas in other Australian states voluntary organizations set up and managed infant health clinics and state governments only later became involved, in order to resolve conflicts or raise standards, Queensland began with government control. From the start, these well-baby clinics were established and maintained by the state government, whose policy precluded any involvement by the voluntary sector in baby clinic management or other aspects of the work of the Maternal and Child Welfare section of the Department of Health and Home Affairs. One organization, the Mothercraft Association of Queensland, attempted to contribute to maternal-infant welfare in the years 1931-1961. This article will discuss how the association worked in a way that was complementary to the government's work, and non-confrontationist, to achieve some of its goals.

Thyroid hormone export from cells: contribution of P-glycoprotein

Verapamil inhibits tri-iodothyronine (T-3) efflux from several cell types, suggesting the involvement of multidrug resistance-associated (MDR) proteins in T-3 transport. The direct involvement of P-glycoprotein (P-gp) has not, however, been investigated. We compared the transport of I-125-T-3 in MDCKII cells that had been transfected with mdr1 cDNA (MDCKII-MDR) versus wild-type MDCKII cells (MDCKII), and examined the effect of conventional (verapamil and nitrendipine) and specific MDR inhibitors (VX 853 and VX 710) on I-125-T-3 efflux. We confirmed by Western blotting the enhanced expression of P-gp in MDCKII-MDR cells. The calculated rate of I-125-T-3 efflux from MDCKII-MDR cells (around 0.30/min) was increased twofold compared with MDCKII cells (around 0.15/min). Overall, cellular accumulation of I-125-T-3 was reduced by 26% in MDCKII-MDR cells compared with MDCKII cells, probably reflecting enhanced export of T-3 from MDCKII-MDR cells rather than reduced cellular uptake, as P-gp typically exports substances from cells. Verapamil lowered the rate of I-125-T-3 efflux from both MDCKII and MDCKII-MDR cells by 42% and 66% respectively, while nitrendipine reduced I-125-T-3 efflux rate by 36% and 48% respectively, suggesting that both substances inhibited other cellular T-3 transporters in addition to P-gp. The specific MDR inhibitors VX 853 and VX 710 had no effect of I-125-T-3 efflux rate from wild-type MDCKII cells but reduced I-125-T-3 export in MDCKII-MDR cells by 50% and 53% respectively. These results have provided the first direct evidence that P-gp exports thyroid hormone from cells.

Ethical perspectives of the Australian live export trade

Objective To examine the ethical perspectives of the Australian live export trade. Design and method The perspectives of farmers and other industry personnel, overseas consumers, the Australian public, veterinarians and the assumed interests of transported animals are compared in relation to the ethical consequences. Animal welfare, societal, personal and professional ethics are identified and the ratification of different perspectives considered. Results and conclusions There are positive and negative aspects of the trade for each stakeholder group, and the overall position adopted by any individual reflects their perspective of the balance of these components. The debate as to whether Australia should continue with the trade will be best served by consideration of the interests of all parties in the trade, including the consumers and animals, which are among the most affected by the trade. There is a need for further research to address the major welfare problems for the animals, an openness to inspection on the part of the trade and balance in media reporting.

Export processing zones and growth triangle development: The case of the BIMP-EAGA, Southeast Asia

Exorts processing zones (EPZs) and growth triangles have been two common Asian initiatives to increase wealth and regional competitiveness in the world economy. Since they are seldom analysed jointly, this paper investigates their mutuality in the development process. Taking the problematic case of the Brunei-Indonesia-Malaysia-Philippines East ASEAN Growth Area (BIMP-EAGA) triangle, we explore the role of EPZs in enhancing regional collaboration, competitiveness, and domestic linkages. Despite the triangle's weak economic complementarities, its processing zones are found capable of advancing development by furthering opportunities in regionalisation/localisation of production. Latterly, trade and investment liberalisation within ASEAN raises broad questions about the rationale of EPZs and growth triangles. Zone-triangle nexuses will require rethinking as, under different regulatory conditions, the zones compete more directly across ASEAN and also with global rivals. Copyright © 2005 John Wiley & Sons, Ltd.

Women with banner Ban the Bomb during Peace march on Sunday April 5th 1964, Brisbane.

Women with banner Ban the Bomb during Peace march, Sunday April 5th Brisbane, Australia, 1964.