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Much attention has been given to the challenges of handling massive data volumes in modern data-intensive science. This paper examines an equally daunting challenge – the diversity of interdisciplinary data, notably research data, and the need to interrelate these data to understand complex systemic problems such as environmental change and its impact. We use the experience of the International Polar Year 2007–8 (IPY) as a case study to examine data management approaches seeking to address issues around complex interdisciplinary science. We find that, while technology is a critical factor in addressing the interdisciplinary dimension of the data intensive science, the technologies developing for exa-scale data volumes differ from those that are needed for extremely distributed and heterogeneous data. Research data will continue to be highly heterogeneous and distributed and will require technologies to be much simpler and more flexible. More importantly, there is a need for both technical and cultural adaptation. We describe a vision of discoverable, open, linked, useful, and safe collections of data, organized and curated using the best principles and practices of information and library science. This vision provides a framework for our discussion and leads us to suggest several short- and long-term strategies to facilitate a socio-technical evolution in the overall science data ecosystem. [ABSTRACT FROM PUBLISHER]

In this study we present evidence that the C-terminus of lipoprotein lipase contains no glycosyl-phosphatidylinositol addition signal and is therefore not a glycosylphosphatidylinositol-anchored protein. Furthermore, we present additional evidence that the C-terminus of lipoprotein lipase is essential for biological function. Flow cytometric analysis and enzyme-activity monitoring experiments revealed no pool of lipo-protein lipase releasable by phosphatidylinositol-specific phospholipase present on the membrane of COS cells transfected with the human lipoprotein lipase gene while, in contrast, a heparin-releasable pool could be demonstrated. [[SUP14]C]Ethanolamine, a constituent of the glycosyiphosphatidylinositol anchor, was not incorporated into lipoprotein lipase during metabolic labeling. C-terminal deletion mutants were constructed and expressed in COS cells to investigate the presence of glycosylphosphatidylinositol addition signal on the C-terminus of human lipoprotein lipase (LPL). The specific activities of the mutants M442 [des-(Leu443-G1y448)-LPL] and M437 [des-(Cys438-Gly448)-LPL] were 78% and 59%. respectively, less than the wild type, while the M432 mutant [des-(Ala433-Gly449)-LPL1 was catalytically inactive. Determination of the stability of the mutants revealed a decreased stability of the M437, compared with wild-type, whereas M442 showed the same stability. Flow cytometric analysis showed sustained membrane expression for all mutants including the inactive M432 mutant. These results suggest that the C-terminus of lipoprotein lipase is essential for maintaining intact catalytic activity hut is not involved in any posttranslational proteolytic processing, including cleavage of a glycosy lphosphatidylinositol addition signal. We therefore conclude that membrane-binding of the lipase is not mediated by such anchoring. [ABSTRACT FROM AUTHOR]

Here we report on the molecular defect that leads to a deficiency of lipoprotein lipase (LPL) activity in a proband of Dutch descent. Southern-blot analysis of the LPL gene from the patient did not reveal any major DNA rearrangements. Sequencing of polymerase-chain-reaction-amplified DNA revealed that the proband is a homozygote for G725C, resulting in a substitution of Pro157 for Arg. This substitution alters a restriction site for PvuII, which allowed rapid identification of the mutant allele in family members. Site-directed mutagenesis and transient expression of the mutant LPL in COS cells produced an enzymaticany inactive protein, establishing the functional significance of this mutation. This naturally occurring mutation which alters the Pro157 adjacent to Asp156 of the proposed catalytic triad, indicates that this region of the protein is indeed crucial for LPL catalytic activity. [ABSTRACT FROM AUTHOR]

Human factor V was subjected to desialation and deglycosylation to investigate the function of the molecular carbohydrate moiety. Removal of 90% of the sialic acid residues resulted in a 1.5-2-fold increase in clotting activity, and up to 70% deglycosylation in a concurrent decrease in clotting activity. Desialation had no effect on thrombin-induced activation, whereas deglycosylated factor V activation was impaired. Lectin-blot experiments with sialic-acidaspecific Limaxflavus agglutinin (LFA), galactose-specific Ricinus communis agglutinin (RCA-II) and mannose-specific concanavalin A on thrombin-induced factor V fragments revealed the presence of carbohydrate residues in fragments B, C1, D and F1F2. Interestingly, sialic acid was present in C1 whilst galactose was not detectable. Fragment F1F2 contained terminal galactose residues. LFA and RCA-Il inhibited the procoagulant activity of native factor V and of desialated factor V respectively. These investigations distinctly indicate the important role of the human factor V carbohydrate moiety in the process of blood coagulation. [ABSTRACT FROM AUTHOR]

Vinculin, a 130-kDa protein discovered in chicken gizzard smooth-muscle cells and subsequently also described in platelets, is believed to be involved in membrane-cytoskeleton interactions. In this study we investigated vinculin distribution in human blood plaletets. Two skeletal fractions and a remaining cytosolic fraction were prepared with a recently described Triton X-100 lysis buffer causing minimal post-lysis breakdown by proteolysis. The presence of vinculin was demonstrated in the membrane skeleton and cytosol of resting and thrombin-activated human platelets. Upon thrombin stimulation vinculin also appeared in the cytoskeleton. This cytoskeletal incorporation was completed during the early stages of platelet aggregation and secretion, when the uptake of myosin, actin-binding protein and talin was still not maximal. We conclude therefore, that vinculin may play an important role in the structural (re)organisation of the human platelet cytoskeleton upon platelet activation. [ABSTRACT FROM AUTHOR]

The article focuses on the National Ocean and Coastal Research (ZKO) Programme funded by the Netherlands Organisation for Scientific Research (NWO) Earth and Life Sciences (ALW). It discusses the purpose of the program to provide scientific analysis of five societal challenges pertaining to the use of the sea and coastal zones. Also mentioned are the five challenges which include safety, economic yield, and water quality, the data management, and coast management in the country.