Development of Gene Expression Markers of Acute Heat-Light Stress in Reef-Building Corals of the Genus Porites

Coral reefs are declining worldwide due to increased incidence of climate-induced coral bleaching, which will have widespread biodiversity and economic impacts. A simple method to measure the sub-bleaching level of heat-light stress experienced by corals would greatly inform reef management practices by making it possible to assess the distribution of bleaching risks among individual reef sites. Gene expression analysis based on quantitative PCR (qPCR) can be used as a diagnostic tool to determine coral condition in situ. We evaluated the expression of 13 candidate genes during heat-light stress in a common Caribbean coral Porites astreoides, and observed strong and consistent changes in gene expression in two independent experiments. Furthermore, we found that the apparent return to baseline expression levels during a recovery phase was rapid, despite visible signs of colony bleaching. We show that the response to acute heat-light stress in P. astreoides can be monitored by measuring the difference in expression of only two genes: Hsp16 and actin. We demonstrate that this assay discriminates between corals sampled from two field sites experiencing different temperatures. We also show that the assay is applicable to an Indo-Pacific congener, P. lobata, and therefore could potentially be used to diagnose acute heat-light stress on coral reefs worldwide

Correction to: Cluster identification, selection, and description in Cluster randomized crossover trials: the PREP-IT trials

An amendment to this paper has been published and can be accessed via the original article

Association of polymorphisms in RGS4 and expression of RGS transcripts in the brains of human alcoholics

Chronic alcoholism leads to neurotoxic effects in the central nervous system. Neuroadaptive changes in the brain may lead to tolerance to, and dependence on, alcohol as a result of alterations in synaptic complexity. G-proteins are negatively regulated by RGS proteins, which are integral to many neural pathways that include neurotransmission, hormonal responses, and chemotactic signals. These considerations, together with findings from microarray analyses of human autopsy brain, suggest that proteins involved in G-protein signalling, specifically the RGS protein family, may play an important role in the functioning of neural systems that are affected by chronic alcohol abuse. We used Real Time PCR to measure the expression of two members of the RGS family, RGS4 and RGS7, in the superior frontal gyrus and primary motor cortex from alcoholic and non-alcoholic cases. Overall, cirrhotic alcoholics had lower expression levels of RGS4 mRNA than controls and non-cirrhotic alcoholics. We also report that the four RGS4 SNPs (SNP1, 4, 7 and 18) may be associated with alcoholism in European Caucasians at the haplotype level. The haplotype T-C-G (SNP1-4-18) may exert a protective effect against alcoholism. © 2010 Elsevier B.V. All rights reserve

Uncertainty principle in niche assessment: A solution to the dilemma redundancy vs. competitive exclusion, and some analytical consequences

There has been a categorically unresolved crucial question in ecology and evolutionary theory for manydecades; perhaps from the times of Charles Darwin himself: Is it possible, under natural conditions,that two species can perform a commonly shared ecological niche? There are two extreme conventionalresponses that have kept divided the scientific community in this regard for almost forty years: (a) No;that is to say, the well-known competitive exclusion principle (CEP). (b) Yes; that is to say, the well-knownhypothesis of full functional redundancy (HFR). Obviously, the reliability of both responses depends on anunderlying and even more essential requisite: that the ecological niche of a given species can be assessedwith such accuracy as we could want in order to detect the degree in which it is shared between coexistingspecies. This article is the seventh in a continuous series of interconnected recent publications that pro-motes an alternative understanding of ecology and evolutionary biology which is in favor of strong andmutually fruitful analytical links between biology and physics. This article analyzes the statistical behav-ior of ecological niches by taking into account two indicators that are essential to perform the ecologicalniche of all species: species diversity per plot (Hp) and eco-kinetic energy (Ee) as a proxy for trophic energyin a scalar field Hp, Eein which an oscillating performance of ecological niches is deployed. According toour results, in the same measurement in which the accuracy of Hpassessments increases (reduction ofHp’s standard deviation: Hp) the accuracy of Eeassessment decreases (increment of Ee), and vice versa, inagreement with a pattern that is completely equivalent to that of the Heisenberg’s uncertainty principlein quantum mechanics (i.e.: Hp· Ee 1/2heec/2 ; where heec: ecological equivalent of Planck’s con-stant found in previous publications). As a result, the ecological niche is, even in principle in addition toin practice, indeterminable with enough exactness to arrive to a categorical response to the above-statedquestion. This means that CEP and HFR are simultaneously true and false in the same measure, becausethe only feasible option to keep the functional stability of ecosystems is a wave-like combination of bothoptions: when species are pushed to a high degree of coexistence (increase of partition of the gradient) in regard to Hpvalues (a trend in favor of HFR), their degree of coexistence in regard to Eevalues dimin-ishes (decrease of partition of the Eegradient, a trend in favor of CEP), and vice versa. The final sections ofthe article highlight the eco-evolutionary, biogeographical and socio-economic meaning of this result, byoffering plausible alternative explanations to a wide spectrum of phenomena that appear to be only par-tially understood so far, e.g.: the contradictory results about the relationship between body size, speciesdiversity and macroevolutionary rates; the general environmental scenario in favor of macroevolutionaryleaps with a low probability to leave footprints in the fossil record; the unnecessary, although stimu-lant, influence of geographic isolation to promote evolutionary changes; the island rule; and the generalmeaning of the interaction between nature and society