Coral Thermal Tolerance: Tuning Gene Expression to Resist Thermal Stress

The acclimatization capacity of corals is a critical consideration in the persistence of coral reefs under stresses imposed by global climate change. The stress history of corals plays a role in subsequent response to heat stress, but the transcriptomic changes associated with these plastic changes have not been previously explored. In order to identify host transcriptomic changes associated with acquired thermal tolerance in the scleractinian coralAcropora millepora, corals preconditioned to a sub-lethal temperature of 3°C below bleaching threshold temperature were compared to both non-preconditioned corals and untreated controls using a cDNA microarray platform. After eight days of hyperthermal challenge, conditions under which non-preconditioned corals bleached and preconditioned corals (thermal-tolerant) maintained Symbiodinium density, a clear differentiation in the transcriptional profiles was revealed among the condition examined. Among these changes, nine differentially expressed genes separated preconditioned corals from non-preconditioned corals, with 42 genes differentially expressed between control and preconditioned treatments, and 70 genes between non-preconditioned corals and controls. Differentially expressed genes included components of an apoptotic signaling cascade, which suggest the inhibition of apoptosis in preconditioned corals. Additionally, lectins and genes involved in response to oxidative stress were also detected. One dominant pattern was the apparent tuning of gene expression observed between preconditioned and non-preconditioned treatments; that is, differences in expression magnitude were more apparent than differences in the identity of genes differentially expressed. Our work revealed a transcriptomic signature underlying the tolerance associated with coral thermal history, and suggests that understanding the molecular mechanisms behind physiological acclimatization would be critical for the modeling of reefs in impending climate change scenarios.

Individuals with mental disabilities: perceptions of work limitations

This research investigates the perceptions that individuals with mental illnesses have about the employment experience as a whole. Survey data from 72 respondents with mental disabilities were used to identify areas of perceived work limitations. Comparisons regarding employee work performance were made between eleven individuals with mental disabilities and their supervisors. Functional limitations identified by respondents with mental disabilities and the characteristic symptoms set forth in the Diagnostic and Statistical Manual of Mental Disorders were compared. Overall findings showed that individuals with mental disabilities in this study had problems in the areas of judgment, initiative, interacting and rapport with co-workers and supervisors, frustration tolerance and coping with job stress, and adapting to changes at work. Comparison of identified work task difficulties with diagnostic criteria indicate active symptomatology to have an effect on job performance. Recommendations regarding occupational therapy assessment approaches and roles to facilitate ADA implementation are presented.