Lateralized behavior and cardiac activity of dogs in response to human emotional vocalizations

Over the recent years, the study of emotional functioning has become one of the central issues in dog cognition. Previous studies showed that dogs can recognize different emotions by looking at human faces and can correctly match the human emotional state with a vocalization having a negative emotional valence. However, to this day, little is known about how dogs perceive and process human non-verbal vocalizations having different emotional valence. The current research provides new insights into emotional functioning of the canine brain by studying dogs' lateralized auditory functions (to provide a first insight into the valence dimension) matched with both behavior and physiological measures of arousal (to study the arousal dimension) in response to playbacks related to the Ekman's six basic human emotions. Overall, our results indicate lateralized brain patterns for the processing of human emotional vocalizations, with the prevalent use of the right hemisphere in the analysis of vocalizations with a clear negative emotional valence (i.e. "fear" and "sadness") and the prevalent use of the left hemisphere in the analysis of positive vocalization ("happiness"). Furthermore, both cardiac activity and behavior response support the hypothesis that dogs are sensitive to emotional cues of human vocalizations

Stay-green protein, defective in Mendel's green cotyledon mutant, acts independent and upstream of pheophorbide a oxygenase in the chlorophyll catabolic pathway

Type C stay-green mutants are defined as being defective in the pathway of chlorophyll breakdown, which involves pheophorbide a oxygenase (PAO), required for loss of green color. By analyzing senescence parameters, such as protein degradation, expression of senescence-associated genes and loss of photosynthetic capacity, we demonstrate that JI2775, the green cotyledon (i) pea line used by Gregor Mendel to establish the law of genetics, is a true type C stay-green mutant. STAY-GREEN (SGR) had earlier been shown to map to the I locus. The defect in JI2775 is due to both reduced expression of SGR and loss of SGR protein function. Regulation of PAO through SGR had been proposed. By determining PAO protein abundance and activity, we show that PAO is unaffected in JI2775. Furthermore we show that pheophorbide a accumulation in the mutant is independent of PAO. When silencing SGR expression in Arabidopsis pao1 mutant, both pheophorbide a accumulation and cell death phenotype, typical features of pao1, are lost. These results confirm that SGR function within the chlorophyll catabolic pathway is independent and upstream of PAO