Forgive and Forget: Differences between Decisional and Emotional Forgiveness

To forgive and forget is a well-known idiom, which has rarely been looked at empirically. In the current experiment, we investigated differences between emotional and decisional forgiveness on forgetting. The present study provides the first empirical support that emotional forgiveness has a strong influence on subsequent incidental forgetting. Specifically, our results demonstrate that emotional forgiveness leads to substantially higher levels of forgetting in respect to offense relevant traits compared to both decisional forgiveness and no forgiveness. This provides evidence for our hypothesized effect that only individuals who have emotionally forgiven a transgression, and not those who just decided to forgive, subsequently forget offense relevant traits attributed to the transgressor.     

A novel Netrin-1–sensitive mechanism promotes local SNARE-mediated exocytosis during axon branching

Developmental axon branching dramatically increases synaptic capacity and neuronal surface area. Netrin-1 promotes branching and synaptogenesis, but the mechanism by which Netrin-1 stimulates plasma membrane expansion is unknown. We demonstrate that SNARE-mediated exocytosis is a prerequisite for axon branching and identify the E3 ubiquitin ligase TRIM9 as a critical catalytic link between Netrin-1 and exocytic SNARE machinery in murine cortical neurons. TRIM9 ligase activity promotes SNARE-mediated vesicle fusion and axon branching in a Netrin-dependent manner. We identified a direct interaction between TRIM9 and the Netrin-1 receptor DCC as well as a Netrin-1–sensitive interaction between TRIM9 and the SNARE component SNAP25. The interaction with SNAP25 negatively regulates SNARE-mediated exocytosis and axon branching in the absence of Netrin-1. Deletion of TRIM9 elevated exocytosis in vitro and increased axon branching in vitro and in vivo. Our data provide a novel model for the spatial regulation of axon branching by Netrin-1, in which localized plasma membrane expansion occurs via TRIM9-dependent regulation of SNARE-mediated vesicle fusion.     

Linking recruitment to trophic factors: revisiting the Beverton--Holt recruitment model from a life history and multispecies perspective

The Beverton--Holt recruitment model can be derived from arguments about evolution of life history traits related to foraging and predation risk, along with spatially localized and temporarily competitive relationships in the habitats where juvenile fish forage and face predation risk while foraging. This derivation explicitly represents two key biotic factors, food supply (I) and predator abundance (R), which appear as a risk ratio (R/I) that facilitates modelling of changes in trophic circumstances and analysis of historical data. The same general recruitment relationship is expected whether the juvenile life history is simple or involves a complex sequence of stanzas; in the complex case, the Beverton--Holt parameters represent weighted averages or integrals of risk ratios over the stanzas. The relationship should also apply in settings where there is complex, mesoscale variation in habitat and predation risk, provided that animals sense this variation and move about so as to achieve similar survival at all mesoscale rearing sites. The model predicts that changes in food and predation risk can be amplified violently in settings where juvenile survival rate is low, producing large changes in recruitment rates over time.     

Survival and persistence of human and ruminant-specific faecal Bacteroidales in freshwater microcosms

Amplification of host-specific markers from Bacteroidales faecal anaerobes can rapidly identify the source of faecal pollution. It is necessary to understand persistence and survival of these markers and marker cells, both to interpret quantitative source-tracking data, and to use such data to predict pathogen occurrence. We measured marker persistence and cell survival of two human (HF134, HF183) and two ruminant (CF128, CF193) faecal Bacteroidales markers, compared with Escherichia coli and enterococci. Freshwater microcosms were inoculated with fresh cattle or human faeces and incubated at 13°C in natural light or darkness. Marker persistence was measured by polymerase chain reaction (PCR) and quantitative PCR. Survival of marker cells was measured by real-time quantitative PCR. There was no difference in persistence between the two human-specific Bacteroidales DNA markers in the light and dark microcosms. Cell survival profiles of the two human markers were also similar; both were significantly affected by light. Ruminant markers persisted and survived longer than human markers (14 versus 6 days respectively). CF193 decreased more rapidly than CF128, and light significantly affected CF128 but not CF193. These results support use of host-specific faecal Bacteroidales markers as indicators of recent faecal pollution, but suggest that caution is needed in interpreting quantitative results to indicate proportional contribution of different sources, as individual markers differ in their survival, persistence and response to environmental variables. The survival and persistence profiles for Bacteroidales markers are consistent with survival profiles for several faecal pathogens.     

KCNE1 is an auxiliary subunit of two distinct ion channel superfamilies

1. Download : Download high-res image (150KB)
2. Download : Download full-size image