Sediment characteristics of a restored saltmarsh and mudflat in a managed realignment scheme in Southeast England

Sediment characteristics and vegetation composition were measured in a restored and natural saltmarsh and mudflat at Wallasea Island managed realignment scheme (Essex, UK) from January to December 2007. The similar sediment characteristics in the restored and natural mudflat indicated that the sediment in the restored mudflat was approaching natural conditions. However, the sediment characteristics in the restored saltmarsh were not becoming similar to those in the natural saltmarsh. The sediment moisture content, organic matter content and porosity were lower while the sediment bulk density, salinity and pH were higher in the restored compared to the natural saltmarsh. The dissimilarities were mainly due to differences in the vegetation abundance and organic matter content. Although, 18 months after restoration the restored saltmarsh was only sparsely vegetated and there was no net change in the sediment characteristics, the occurrence of Salicornia europaea L. demonstrated that pioneer saltmarsh vegetation establishment preceded the development of sediment characteristics.     

Insulin sensitivity is not associated with palmitoleate availability in obese humans

We evaluated whether insulin resistance in obese people is associated with decreased plasma palmitoleate availability. Palmitoleate content (percentage and absolute concentrations) in FFA and VLDL was measured in obese subjects who were either insulin resistant (IR) or insulin sensitive (IS), based on assessment of multiorgan (skeletal muscle, liver, and adipose tissue) insulin sensitivity by using the hyperinsulinemic-euglycemic clamp procedure in conjunction with infusion of stable isotopically labeled tracers. Plasma palmitoleate concentration and the relative contribution of palmitoleate to total plasma FFA concentration in the IS group (0.018 ± 0.002 mmol/l and 4.4% ± 0.2%, respectively) were not significantly different than values in the IR group (0.023 ± 0.003 mmol/l and 4.4% ± 0.4%, respectively). Plasma VLDL-triglyceride palmitoleate concentration and the proportion of VLDL fatty acids as palmitoleate in the IS group (0.09 ± 0.02 mmol/l and 5.7 ± 0.3%, respectively) were also not significantly different than those in the IR group (0.16 ± 0.04 mmol/l and 5.0% ± 0.4%, respectively). These data demonstrate that decreased palmitoleate in plasma and in VLDL is not associated with insulin resistance in skeletal muscle, liver, or adipose tissue in obese people.     

Chlorite dismutases, DyPs, and EfeB: 3 microbial heme enzyme families comprise the CDE structural superfamily

Heme proteins are extremely diverse, widespread, and versatile biocatalysts, sensors, and molecular transporters. The chlorite dismutase family of hemoproteins received its name due to the ability of the first-isolated members to detoxify anthropogenic ClO₂⁻, a function believed to have evolved only in the last few decades. Family members have since been found in 15 bacterial and archaeal genera, suggesting ancient roots. A structure- and sequence-based examination of the family is presented, in which key sequence and structural motifs are identified, and possible functions for family proteins are proposed. Newly identified structural homologies moreover demonstrate clear connections to two other large, ancient, and functionally mysterious protein families. We propose calling them collectively the CDE superfamily of heme proteins.     

A new Triassic decapod, <Emphasis Type="Italic">Platykotta akaina</Emphasis>, from the Arabian shelf of the northern United Arab Emirates: earliest occurrence of the Anomura

A Triassic decapod crustacean is described here for the first time from the Norian-Rhaetian Ghalilah Formation of the Musandam Peninsula, United Arab Emirates. The single specimen Platykotta akaina n. gen n. sp. is referred to a new family Platykottidae. The studied crustacean, initially with only the ventral exposure preserved, was collected from shallow-water, burrowed limestones. Using a chemical preparation, the dorsal view revealed a well-preserved, chitinous, granular carapace exhibiting characteristic carapace morphology and groove pattern of the Eocarcinoidea, the superfamily to which the new family is assigned. The dorsal view together with the ventral surface, rarely seen in the fossil record, provide new insight into the morphology of representatives of the Eocarcinoidea.     

The long and the short of it: SD1 polymorphism and the evolution of growth trait divergence in U.S. weedy rice

Growth-related traits, such as greater height, greater biomass, faster growth rate and early flowering, are thought to enhance competitiveness of agricultural weeds. However, weedy rice, a conspecific weed of cultivated rice (Oryza sativa L.), displays variation for growth traits. In the United States, separately evolved weedy rice groups have been shown to share genomic identity with exotic domesticated cultivars. Through a common garden experiment, we investigated whether growth trait divergence has occurred among U.S. weeds and their putative cultivated progenitors. We also determined polymorphism patterns in the growth candidate gene, SD1, to assess its possible role in the evolution of divergent phenotypes. We found considerable growth trait variation among weed groups, suggesting that growth trait convergence is not evident among weedy populations. Phenotypic divergence of weedy rice from cultivated ancestors is most apparent for flowering time. Introgression of a chromosomal block containing the SD1 allele from tropical japonica, the predominant U.S. rice cultivar, was detected in one weedy rice population and is associated with a change in growth patterns in this group. This study demonstrates the role of introgressive hybridization in evolutionary divergence of an important weed.     

Expression and characterization of murine hevin (SC1), a member of the SPARC family of matricellular proteins.

Hevin, also known as SC1, MAST 9, SPARC-like 1, RAGS1 and ECM2, is a member of the SPARC-related family of matricellular proteins. Mouse hevin is 53% identical to mouse SPARC, and both proteins share a follistatin-like module and an extracellular Ca(2+)-binding (E-C) domain. SPARC functions as a modulator of cell-matrix interactions, a regulator of growth factor activity, a de-adhesive protein, and a cell cycle inhibitor. Although the functions of mouse hevin are unknown, its human orthologue has been shown to be de-adhesive for endothelial cells. We now report the production of recombinant mouse hevin in insect cells through the use of a baculoviral expression system and its purification by anion-exchange, size-exclusion chromatography, and isoelectric focusing. Furthermore, we have produced rat anti-hevin monoclonal antibodies (MAbs) that have been characterized by indirect and capture ELISAs, immunoblotting, immunoprecipitation, and immunohistochemistry (IHC). Recombinant hevin, present as a soluble factor or bound to tissue-culture plastic, inhibited the spreading of bovine aortic endothelial cells in vitro. IHC analysis of hevin in normal human and mouse tissues revealed a limited expression pattern in many tissues, with particularly dominant staining in dermis, ducts, vasculature, muscle, and brain. In lung and pancreatic tumor xenografts, we found distinct reactivity with MAbs that were selective for stromal cells, tumor cells, and/or endothelial cells. Although similar to SPARC in its anti-adhesive activities, hevin nevertheless exhibits a distinctive histological distribution that, in certain invasive tumors, is associated with desmoplasia.     

Characterization of the preprotein and amino acid transporter gene family in Arabidopsis

Seventeen loci encode proteins of the preprotein and amino acid transporter family in Arabidopsis (Arabidopsis thaliana). Some of these genes have arisen from recent duplications and are not in annotated duplicated regions of the Arabidopsis genome. In comparison to a number of other eukaryotic organisms, this family of proteins has greatly expanded in plants, with 24 loci in rice (Oryza sativa). Most of the Arabidopsis and rice genes are orthologous, indicating expansion of this family before monocot and dicot divergence. In vitro protein uptake assays, in vivo green fluorescent protein tagging, and immunological analyses of selected proteins determined either mitochondrial or plastidic localization for 10 and six proteins, respectively. The protein encoded by At5g24650 is targeted to both mitochondria and chloroplasts and, to our knowledge, is the first membrane protein reported to be targeted to mitochondria and chloroplasts. Three genes encoded translocase of the inner mitochondrial membrane (TIM)17-like proteins, three TIM23-like proteins, and three outer envelope protein16-like proteins in Arabidopsis. The identity of Arabidopsis TIM22-like proteins is most likely a protein encoded by At3g10110/At1g18320, based on phylogenetic analysis, subcellular localization, and complementation of a yeast (Saccharomyces cerevisiae) mutant and coexpression analysis. The lack of a preprotein and amino acid transporter domain in some proteins, localization in mitochondria, plastids, or both, variation in gene structure, and the differences in expression profiles indicate that the function of this family has diverged in plants beyond roles in protein translocation.