Feeding, Respiration and Excretion of the Copepod Calanus hyperboreus from Baffin Bay, Including Waters Contaminated by Oil Seeps

Metabolic processes in eastern arctic copepods Calanus hyperboreus were analyzed during the post-bloom period (August-September). Mixed adult and subadult copepods were collected from 12 stations in Baffin Bay (Davis Strait to Lancaster Sound) by trawling from 0-300 m. Measurements were made of clearance rate, O2-consumption and NH3 excretion. The cruise track included 6 stations in oil-seep contaminated waters of Scott Inlet and Buchan Gulf. Physiological parameters for populations of C. hyperboreus from the latter stations were compared with those from non-seep stations. Mean O2 consumption rates (0.309 - 0.907 µl O2 / mg dry wt / h) for all stations were similar to those described for Antarctic calanoid species but were higher than reported for more northern arctic waters. Mean ammonia excretion rates (0.023 - 0.071 µg N / mg dry wt / h) were somewhat lower than reported for comparable Antarctic species and were similar to values from other eastern arctic studies. O:N ratios for 11 of the 12 stations occupied ranged between 8.4 and 22.1, indicative of protein-based metabolism. The single exception was a High Arctic station with O:N ratio 43.6. Clearance rates were low to nonexistant for all stations. Most of the non-feeding values came from the Scott Inlet-Buchan Gulf region of western Baffin Bay. At those stations in this region a strong negative correlation (P<.01) exists between clearance rate and hydrocarbon contamination. This suggests that in the oil-seep region of Baffin Bay feeding may be suppressed in Calanus hyperboreus by low concentrations of petroleum hydrocarbons derived from sub-sea seepage.Key words: zooplankton, Calanus hyperboreus, Arctic, metabolism, oil seep, petroleum, hydrocarbons, oil pollutionMots clés: zooplancton, Calanus hyperboreus, Arctique, métabolisme, suitements de pétrole, pétrole, hydrocarbures, pollution par les hydrocarbure

Cross-modal individual recognition in wild African lions

Individual recognition is considered to have been fundamental in the evolution of complex social systems and is thought to be a widespread ability throughout the animal kingdom. Although robust evidence for individual recognition remains limited, recent experimental paradigms that examine cross-modal processing have demonstrated individual recognition in a range of captive non-human animals. It is now highly relevant to test whether cross-modal individual recognition exists within wild populations and thus examine how it is employed during natural social interactions. We address this question by testing audio–visual cross-modal individual recognition in wild African lions (Panthera leo) using an expectancy-violation paradigm. When presented with a scenario where the playback of a loud-call (roaring) broadcast from behind a visual block is incongruent with the conspecific previously seen there, subjects responded more strongly than during the congruent scenario where the call and individual matched. These findings suggest that lions are capable of audio–visual cross-modal individual recognition and provide a useful method for studying this ability in wild populations

TREM2 Lipid Sensing Sustains the Microglial Response in an Alzheimer’s Disease Model

SummaryTriggering receptor expressed on myeloid cells 2 (TREM2) is a microglial surface receptor that triggers intracellular protein tyrosine phosphorylation. Recent genome-wide association studies have shown that a rare R47H mutation of TREM2 correlates with a substantial increase in the risk of developing Alzheimer’s disease (AD). To address the basis for this genetic association, we studied TREM2 deficiency in the 5XFAD mouse model of AD. We found that TREM2 deficiency and haploinsufficiency augment β-amyloid (Aβ) accumulation due to a dysfunctional response of microglia, which fail to cluster around Aβ plaques and become apoptotic. We further demonstrate that TREM2 senses a broad array of anionic and zwitterionic lipids known to associate with fibrillar Aβ in lipid membranes and to be exposed on the surface of damaged neurons. Remarkably, the R47H mutation impairs TREM2 detection of lipid ligands. Thus, TREM2 detects damage-associated lipid patterns associated with neurodegeneration, sustaining the microglial response to Aβ accumulation

Expression in Aneuploid Drosophila S2 Cells

Analysis of the relationship between gene copy number and gene expression in aneuploid male Drosophila cells reveals a global compensation mechanism in addition to X chromosome-specific dosage compensation

Identification of Common Genetic Variants Influencing Spontaneous Dizygotic Twinning and Female Fertility.

Spontaneous dizygotic (DZ) twinning occurs in 1%-4% of women, with familial clustering and unknown physiological pathways and genetic origin. DZ twinning might index increased fertility and has distinct health implications for mother and child. We performed a GWAS in 1,980 mothers of spontaneous DZ twins and 12,953 control subjects. Findings were replicated in a large Icelandic cohort and tested for association across a broad range of fertility traits in women. Two SNPs were identified (rs11031006 near FSHB, p = 1.54 × 10(-9), and rs17293443 in SMAD3, p = 1.57 × 10(-8)) and replicated (p = 3 × 10(-3) and p = 1.44 × 10(-4), respectively). Based on ∼90,000 births in Iceland, the risk of a mother delivering twins increased by 18% for each copy of allele rs11031006-G and 9% for rs17293443-C. A higher polygenic risk score (PRS) for DZ twinning, calculated based on the results of the DZ twinning GWAS, was significantly associated with DZ twinning in Iceland (p = 0.001). A higher PRS was also associated with having children (p = 0.01), greater lifetime parity (p = 0.03), and earlier age at first child (p = 0.02). Allele rs11031006-G was associated with higher serum FSH levels, earlier age at menarche, earlier age at first child, higher lifetime parity, lower PCOS risk, and earlier age at menopause. Conversely, rs17293443-C was associated with later age at last child. We identified robust genetic risk variants for DZ twinning: one near FSHB and a second within SMAD3, the product of which plays an important role in gonadal responsiveness to FSH. These loci contribute to crucial aspects of reproductive capacity and health.Support for the Netherlands Twin Register was obtained from the Netherlands Organization for Scientific Research (NWO) and The Netherlands Organization for Health Research and Development (ZonMW) grants, 904-61-193,480-04-004, 400-05-717, Addiction-31160008, 911-09-032, Biobanking and Biomolecular Resources Research Infrastructure (BBMRI –NL, 184.021.007); Royal Netherlands Academy of Science Professor Award (PAH/6635) to DIB; European Research Council (ERC-230374 and ERC-284167); Rutgers University Cell and DNA Repository (NIMH U24 MH068457-06), the Avera Institute, Sioux Falls, South Dakota (USA) and the National Institutes of Health (NIH R01 HD042157-01A1). Part of the genotyping was funded by the Genetic Association Information Network (GAIN) of the Foundation for the National Institutes of Health and Grand Opportunity grants 1RC2 MH089951). We acknowledge support from VU Amsterdam and the Institute for Health and Care Research (EMGO+). The Berghofer Medical Research Institute (QIMR) study was supported by grants from the National Health and Medical Research Council (NHMRC) of Australia (241944, 339462, 389927, 389875, 389891, 389892, 389938, 443036, 442915, 442981, 496610, 496739, 552485, 552498, 1050208, 1075175). Dale R. Nyholt was supported by the Australian Research Council (ARC) Future Fellowship (FT0991022), NHMRC Research Fellowship (APP0613674) Schemes and by the Visiting Professors Programme (VPP) of the Royal Netherlands Academy of Arts and Sciences (KNAW). Allan F. McRae was supported by an NRMRC Career Development Fellowship (APP1083656). Grant W. Montgomery was supported by NIH grant (HD042157, a collaborative study of the genetics of DZ twinning) and NHMRC Fellowship (GNT1078399). The Minnesota Center for Twin and Family Research (MCTFR) was supported in part by USPHS Grants from the National Institute on Alcohol Abuse and Alcoholism (AA09367 and AA11886), and the National Institute on Drug Abuse (DA05147, DA13240, and DA024417). We would like to thank also 23andMe's consented research participants for contributing data on age at menarche for the FSHB gene locus and the Twinning Gwas Consortium (TGC). Co-authors from: Finland (Anu Loukola, Juho Wedenoja, Emmi Tikkanen, Beenish Qaiser), Sweden (Nancy Pedersen, Andrea Ganna), United kingdom King's College London (Department of Twin Research & Genetic Epidemiology: Pirro Hysi, Massimo Mangino), Institute of Psychiatry, Psychology & Neuroscience, Medical Research Council Social, Genetic and Developmental Psychiatry Centre (Eva Krapohl, Andrew McMillan).This is the author accepted manuscript. The final version is available from Elsevier via http://dx.doi.org/10.1016/j.ajhg.2016.03.00