Oxygen‐mediated plasticity confers hypoxia tolerance in a corallivorous polychaete

There is mounting evidence that the deoxygenation of coastal marine ecosystems has been underestimated, particularly in the tropics. These physical conditions appear to have far‐reaching consequences for marine communities and have been associated with mass mortalities. Yet little is known about hypoxia in tropical habitats or about the effects it has on reef‐associated benthic organisms. We explored patterns of dissolved oxygen (DO) throughout Almirante Bay, Panama and found a hypoxic gradient, with areas closest to the mainland having the largest diel variation in DO, as well as more frequent persistent hypoxia. We then designed a laboratory experiment replicating the most extreme in situ DO regime found on shallow patch reefs (3 m) to assess the response of the corallivorous fireworm, Hermodice carnaculata to hypoxia. Worms were exposed to hypoxic conditions (8 hr ~ 1 mg/L or 3.2 kPa) 16 times over an 8‐week period, and at 4 and 8 weeks, their oxygen consumption (respiration rates) was measured upon reoxygenation, along with regrowth of severed gills. Exposure to low DO resulted in worms regenerating significantly larger gills compared to worms under normoxia. This response to low DO was coupled with an ability to maintain elevated oxygen consumption/respiration rates after low DO exposure. In contrast, worms from the normoxic treatment had significantly depressed respiration rates after being exposed to low DO (week 8). This indicates that oxygen‐mediated plasticity in both gill morphology and physiology may confer tolerance to increasingly frequent and severe hypoxia in one important coral predator associated with reef decline.     

High School Gay–Straight Alliances (GSAs) and Young Adult Well-Being: An Examination of GSA Presence,Participation, and Perceived Effectiveness

Gay–Straight Alliances (GSAs) are student-led, school-based clubs that aim to provide a safe environment in the school context for lesbian, gay, bisexual, and transgender (LGBT) students, as well as their straight allies. The present study examines the potential for GSAs to support positive youth development and to reduce associations among LGBT-specific school victimization and negative young adult well-being. The sample includes 245 LGBT young adults, ages 21–25, who retrospectively reported on the presence of a GSA in their high school, their participation in their school's GSA, and their perceptions of whether or not their GSA was effective in improving school safety. Findings revealed that the presence of a GSA, participation in a GSA, and perceived GSA effectiveness in promoting school safety were differentially associated with young adult well-being and, in some cases, buffered the negative association between LGBT-specific school victimization and well-being. Implications for future research and schools are discussed.     

PGC-1 Coactivators Regulate MITF and the Tanning Response

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Highlights? PGC-1 induces pigment formation in melanocytes ? PGC-1s activate expression of MITF ? α-MSH induces PGC-1s, which are required for induction of melanogenic genes ? eQTLs in human PGC-1β are associated with tanning ability and melanoma protection