白化菠萝蜜茎2个蛋白激酶和4个转录因子家族分析

为探究蛋白激酶(PKs)和转录因子(TFs)在白化菠萝蜜(Artocarpus heterophyllus)幼苗茎次生生长中的表达变化,基于转录组数据对其差异表达基因(DEGs)进行预测及分类,并对挑选出的2个PKs和4个TFs家族构建系统进化树。结果表明,胞质类受体激酶(RLCK)-VIII家族的DEGs上下调表达各4个,亮氨酸富集重复类受体激酶(LRR-RLK)-X家族Xa和Xb-2分支中的DEGs均下调表达,Xb-1中的均上调,TCP家族的20个DEGs中有15个上调表达,zf-HD和GRF家族中的大多数DEGs上调表达,Alfin-like家族中的DEGs均下调表达。因此,这表明6个家族可能在菠萝蜜茎的次生生长过程和应对非生物胁迫中发挥重要作用。     

Effect of the early social environment on behavioural and genomic responses to a social challenge in a cooperatively breeding vertebrate

The early social environment can have substantial, lifelong effects on vertebrate social behaviour, which can be mediated by developmental plasticity of brain gene expression. Early‐life effects can influence immediate behavioural responses towards later‐life social challenges and can activate different gene expression responses. However, while genomic responses to social challenges have been reported frequently, how developmental experience influences the shape of these genomic reaction norms remains largely unexplored. We tested how manipulating the early social environment of juvenile cooperatively breeding cichlids, Neolamprologus pulcher, affects their behavioural and brain genomic responses when competing over a resource. Juveniles were reared either with or without a breeder pair and a helper. Fish reared with family members behaved more appropriately in the competition than when reared without. We investigated whether the different social rearing environments also affected the genomic responses to the social challenge. A set of candidate genes, coding for hormones and receptors influencing social behaviour, were measured in the telencephalon and hypothalamus. Social environment and social challenge both influenced gene expression of egr‐1 (early growth response 1) and gr1 (glucocorticoid receptor 1) in the telencephalon and of bdnf (brain‐derived neurotrophic factor) in the hypothalamus. A global analysis of the 11 expression patterns in the two brain areas showed that neurogenomic states diverged more strongly between intruder fish and control fish when they had been reared in a natural social setting. Our results show that same molecular pathways may be used differently in response to a social challenge depending on early‐life experiences.     

Manipulation of colony environment modulates honey bee aggression and brain gene expression

The social environment plays an essential role in shaping behavior for most animals. Social effects on behavior are often linked to changes in brain gene expression. In the honey bee (Apis mellifera L.), social modulation of individual aggression allows colonies to adjust the intensity with which they defend their hive in response to predation threat. Previous research has showed social effects on both aggression and aggression‐related brain gene expression in honey bees, caused by alarm pheromone and unknown factors related to colony genotype. For example, some bees from less aggressive genetic stock reared in colonies with genetic predispositions toward increased aggression show both increased aggression and more aggressive‐like brain gene expression profiles. We tested the hypothesis that exposure to a colony environment influenced by high levels of predation threat results in increased aggression and aggressive‐like gene expression patterns in individual bees. We assessed gene expression using four marker genes. Experimentally induced predation threats modified behavior, but the effect was opposite of our predictions: disturbed colonies showed decreased aggression. Disturbed colonies also decreased foraging activity, suggesting that they did not habituate to threats; other explanations for this finding are discussed. Bees in disturbed colonies also showed changes in brain gene expression, some of which paralleled behavioral findings. These results show that bee aggression and associated molecular processes are subject to complex social influences .     

Sickness and Aggressive Behavior in Dominant and Subordinate Mice*

Sick animals show a set of organized behavioral changes (sickness behavior), which is the result of a motivational re‐organization of the behavior as a whole. Sickness behavior display can be influenced by the social context. In this work, we sought to investigate the regulation of sickness behavior within a pair of mice in the presence of an intruder mouse. Dominant and subordinate mice were treated with the bacterial endotoxin lipopolysaccharide (LPS) and were challenged with the presence of an intruder mouse. LPS effects depended on ranking and social context. Even though dominant mice displayed more agonistic interaction towards the intruder, subordinate mice displayed agonistic behavior towards the intruder when their dominant companion was treated with LPS. The results show that, not only sickness behavior is differentially expressed among different social ranks, but also that sickness behavior is related to different reactions among surrounding animals. These data are relevant for a biological approach to the relation between sickness behavior and social behavior.     

Social context affects behavior,preoptic area gene expression,and response to D2 receptor manipulation during territorial defense in a cichlid fish

Social context often has profound effects on behavior, yet the neural and molecular mechanisms which mediate flexible behavioral responses to different social environments are not well understood. We used the African cichlid fish, Astatotilapia burtoni, to examine aggressive defense behavior across three social contexts representing different motivational states: a reproductive opportunity, a familiar male and a neutral context. To elucidate how differences in behavior across contexts may be mediated by neural gene expression, we examined gene expression in the preoptic area, a brain region known to control male aggressive and sexual behavior. We show that social context has broad effects on preoptic gene expression. Specifically, we found that the expression of genes encoding nonapeptides and sex steroid receptors are upregulated in the familiar male context. Furthermore, circulating levels of testosterone and cortisol varied markedly depending on social context. We also manipulated the D2 receptor (D2R) in each social context, given that it has been implicated in mediating context‐dependent behavior. We found that a D2R agonist reduced intruder‐directed aggression in the reproductive opportunity and familiar male contexts, while a D2R antagonist inhibited intruder‐directed aggression in the reproductive opportunity context and increased aggression in the neutral context. Our results demonstrate a critical role for preoptic gene expression, as well as circulating steroid hormone levels, in encoding information from the social environment and in shaping adaptive behavior. In addition, they provide further evidence for a role of D2R in context‐dependent behavior.