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Chiu, M.-T.

Publications and source records attributed to Chiu, M.-T..

3 recordsLinked to original sources

Asymmetric Neurogenomic States Emerge in Winners and Losers After Social Competition

Winner and loser effects can influence future aggressive behavior following social competition, but their neurogenomic basis remains poorly understood. Using Betta splendens, we integrated behavioral analyses, whole-brain RNA sequencing, and genomic coexpression network analyses to investigate how social experiences influence enduring behavioral and molecular states. Winners showed increased attack frequency, whereas losers prolonged aggressive latency, indicating effects on distinct behavioral aspects. Winners and losers initially shared acute responses in terms of both gene expression and network coordination but subsequently diverged through outcome-specific patterns of network reorganization, despite few persistent differentially expressed genes. This divergence was asymmetric and involved multiple components: immune-related networks showed notable contrasts, with winners displaying anticipated postconflict coordination but losers instead showing discoordination, whereas neuroendocrine and purinergic networks diverged over distinct temporal scales. These findings highlight transcriptomic network-level remodeling as a potential key feature of the winner-loser effect.

animal behavior and cognition↗

A potential pathway that links intron retention with the physiological recovery by a Japanese herbal medicine

Our previous experiments with klotho mice (i.e., klotho knockout mice) showed that aberrant intron retention (IR) occurs in a pre-symptomatic state of aging and can be restored to the normal state by administration of Juzentaihoto (JTT), a formula of the Japanese herbal medicine (referred to as kampo; Okada et al., 2021). To explain that this phenomenon is not just a specific example observed in klotho mice, but is due to a universal cause that may be common in a pre-symptomatic state, we re-analyzed the data for genes that were differentially expressed in the klotho liver in response to JTT. Our data showed that AMPK signaling was activated in these mice, resulting in inhibition of anabolic pathways including protein synthesis and activation of catabolic pathways including lipolysis in various organs. These data were consistent with the observation that klotho mice appeared to be in a perpetual state of pseudo-starvation, i.e., based on their overall metabolic profile. The abnormally increased incidence of IR (IncIR) in the liver of klotho mice could be classified into three types according to their transcriptional status, revealing that each of all the three types of IncIR was caused by AMPK activation, a consequence of the pseudo-starvation state exhibited by these mice. Furthermore, we showed that both the transcriptional drift variance and the IR drift variance can be useful for visually assessing recovery from the pseudo-starvation state of klotho mice after administration of JTT. With these data, we propose a novel pathway linking intron retention to changes in the physiological state such as starvation, resulting in the maintenance of cellular homeostasis.

bioinformatics↗

A unique neurogenomic state emerges after aggressive confrontations in males of the fish Betta splendens

Territorial defense involves frequent aggressive confrontations with competitors, but little is known about how brain-transcriptomic profiles change between individuals competing for territory establishment. Our previous study elucidated that brain-transcriptomic synchronization occurs in a pair-specific manner between two males of the fish Betta splendens during fighting, reflecting a mutual assessment process between them at the level of gene expression. Here we evaluated how the brain-transcriptomic profiles of opponents change immediately after shifting their social status (i.e., the winner/loser has emerged) and 30 min after this shift. We showed that unique and carryover hypotheses can be adapted to this system, in which changes in the expression of certain genes are unique to different fighting stages and in which the expression patterns of certain genes are transiently or persistently changed across all fighting stages. Interestingly, the specificity of the brain-transcriptomic synchronization of a pair during fighting was gradually lost after fighting ceased, because of the decrease in the variance in gene expression across all individuals, leading to the emergence of a basal neurogenomic state. Strikingly, this unique state was more basal than the state that existed in the before-fighting group and resulted in the reduced and consistent expression of genes across all individuals. In spite of the consistent and basal overall gene expression in each individual in this state, expression changes for genes related to metabolism, learning and memory, and autism still differentiated losers from winners. The fighting system using male B. splendens thus provides a promising platform for investigating neurogenomic states of aggression in vertebrates. Author summaryCompetitive interactions involve complex decision-making tasks that are shaped by mutual feedback between participants. When two animals interact, transcriptomes across their brains synchronize in a way that reflects how they assess and predict the others fighting ability and react to each others decisions. Here, we elucidated the gradual loss of brain-transcriptomic synchrony between interacting opponents after their interaction ceased, leading to the emergence of a basal neurogenomic state, in which the variations in gene expression were reduced to a minimum among all individuals. This basal neurogenomic state shares common characteristics with the hibernation state, which animals adopt to minimize their metabolic rates to cope with harsh environmental conditions. We demonstrated that this unique neurogenomic state, which is newly characterized in the present study, is composed of the expression of a unique set of genes, each of which was presumably minimally required for survival, providing a hypothesis that this state represents the smallest unit of neurogenomic activity for sustaining an active life.

molecular biology↗