17 research outputs found
Cutting Edge Structural Protein from the Jaws of Nereis virens
The fang-like jaws of the marine polychaete Nereis virens possess remarkable mechanical properties considering their high protein content and lack of mineralization. Hardness and stiffness properties in the jaw tip are comparable to human dentin and are achieved by extensive coordination of Zn2+ by a histidine-rich protein framework. In the present study, the predominant protein in the jaw tip, Nvjp-1, was purified and characterized by partial peptide mapping and molecular cloning of a partial cDNA from a jaw pulp library. The deduced amino acid sequence revealed an ∼38 kDa histidine-rich protein rich in glycine and histidine (∼36 and 27%, respectively) with no well-defined repetitive motifs. The effects of pH and metal treatment on aggregation, secondary structure, and hydrodynamic properties of recombinant Nvjp-1 are described. Notably, Zn treatment induced the formation of amyloid-like fibers
Elevated Fe(II) and Dissolved Fe in Hypoxic Shelf Waters off Oregon and Washington: An Enhanced Source of Iron to Coastal Upwelling Regimes
A demographic analysis of the family structure experiences of children in the United States
Family structure, Children, Marriage, Cohabitation, J10,
Recommended from our members
The SNP rs755622 is associated with immune activation in glioblastoma
Intratumoral heterogeneity is a defining hallmark of glioblastoma, driving drug resistant and ultimately recurrence. Many somatic drivers of microenvironmental change have been shown to affect this heterogeneity and ultimately treatment response. However, little is known about how germline mutations effect the tumoral microenvironment. Here, we find that the single-nucleotide polymorphism (SNP) rs755622 in promoter of the cytokine macrophage migration inhibitory factor (MIF), is associated with increased leukocyte infiltration in glioblastoma. Furthermore, we identified an association between rs755622 and lactotransferrin expression, which could also be used as a biomarker for immune-infiltrated tumors. These findings demonstrate that a germline SNP in the promoter region of MIF may impact the immune microenvironment and further reveals a link between lactotransferrin and immune activation
Individual Foraging Strategies Reveal Niche Overlap between Endangered Galapagos Pinnipeds
Villegas-Amtmann S, Jeglinski J, Costa DP, Robinson PW, Trillmich F. Individual Foraging Strategies Reveal Niche Overlap between Endangered Galapagos Pinnipeds. PLoS ONE. 2013;8(8): e70748.Most competition studies between species are conducted from a population-level approach. Few studies have examined inter-specific competition in conjunction with intra-specific competition, with an individual-based approach. To our knowledge, none has been conducted on marine top predators. Sympatric Galapagos fur seals (Arctocephalus galapagoensis) and sea lions (Zalophus wollebaeki) share similar geographic habitats and potentially compete. We studied their foraging niche overlap at Cabo Douglas, Fernandina Island from simultaneously collected dive and movement data to examine spatial and temporal inter- and intra-specific competition. Sea lions exhibited 3 foraging strategies (shallow, intermediate and deep) indicating intra-specific competition. Fur seals exhibited one foraging strategy, diving predominantly at night, between 0–80 m depth and mostly at 19–22 h. Most sea lion dives also occurred at night (63%), between 0–40 m, within fur seals' diving depth range. 34% of sea lions night dives occurred at 19–22 h, when fur seals dived the most, but most of them occurred at dawn and dusk, when fur seals exhibited the least amount of dives. Fur seals and sea lions foraging behavior overlapped at 19 and 21 h between 0–30 m depths. Sea lions from the deep diving strategy exhibited the greatest foraging overlap with fur seals, in time (19 h), depth during overlapping time (21–24 m), and foraging range (37.7%). Fur seals foraging range was larger. Cabo Douglas northwest coastal area, region of highest diving density, is a foraging “hot spot” for both species. Fur seals and sea lions foraging niche overlap occurred, but segregation also occurred; fur seals primarily dived at night, while sea lions exhibited night and day diving. Both species exploited depths and areas exclusive to their species. Niche breadth generally increases with environmental uncertainty and decreased productivity. Potential competition between these species could be greater during warmer periods when prey availability is reduced