Biology subjects

Wada, R.

Publications and source records attributed to Wada, R..

4 recordsLinked to original sources

bioRxiv2024

How does immediate auditory feedback coupled to locomotion influence the spontaneous actions of rats?

Sense of agency is a subjective experience that is difficult to examine in animals and preverbal infants. In animals and infants, the sensory monitoring of self-motion, which is the basis of this sense, and the contingency between self-motion and sensory feedback are investigated. Here, we performed experiments on rats using locomotor movements and auditory feedback of pulsed sounds with real-time changes in pulse interval corresponding to the velocity of locomotion, and tested whether rats change their locomotion depending on the degree of contingency between locomotion and auditory feedback. The results showed that rats increased their locomotion distance when the pulse interval of sound changed in accordance with the velocity of locomotion. However, this effect was not long-lasting. This study provides a simple and convenient method to examine the awareness of the contingency between self-motion and auditory feedback in a wide range of animal species without long-term training, and is expected to be a useful tool for comparisons with humans.

animal behavior and cognition↗

bioRxiv2024

Beyond dichotomy: diversity of rat's ultrasonic vocalizations

Rats emit ultrasonic vocalizations (USVs) in diverse contexts, and these USVs are thought to serve many biological functions, such as socio-coordinating and alarming functions. In particular, rat USVs have been established as a good model for studying emotional expressions. Since the discovery of USVs in rats, it has gradually been revealed that two families of juvenile and adult rat USVs with distinct acoustic features are closely linked to different affective states: 50-kHz (high-short) calls are associated with positive affective states, whereas 22-kHz (low-long) calls are associated with negative affective states. Although various subtypes within high-short and low-long calls have been proposed and used, most studies adopt the dichotomous framework of first dividing USVs into high-short or low-long calls. The diversity of rat USVs may have been overlooked due to this high-short / low-long dichotomous framework, as such labeling could discourage reporting of actual measured acoustic properties. Considering that several recent studies claim to have found new USV categories outside this framework, we conducted a systematic survey of descriptions of rat USVs in the literature. We identified 15 articles reporting USVs that are outside the dichotomous framework. Our results support the existence of diverse USVs beyond the dichotomy, highlighting the importance of research on a broader range of vocalizations that might reflect complex affective states beyond the simple distinction between positive and negative.

animal behavior and cognition↗

bioRxiv2024

Drug-induced cis-regulatory elements in human hepatocytes affect molecular phenotypes associated with adverse reactions

BackgroundGenomic variations contribute to the phenotypic diversity of individuals. A number of polymorphisms in protein-coding regions that alter drug efficacy or lead to adverse reactions have been characterized; however, noncoding regions that affect drug responses are largely overlooked, except for a limited number of well-studied enhancers. ResultsWe conducted a quantitative assessment of cis-regulatory elements (CREs) based on transcription initiation profiling of mRNAs and noncoding RNAs, including enhancer RNAs, by using CAGE (Cap Analysis of Gene Expression). Candidate CREs identified in a hepatocellular carcinoma HepG2 cell line with stable expression of drug-responsive transcription factor pregnane X receptor (PXR) were further narrowed down by integrating data of PXR-binding sites in human primary hepatocytes and genome-wide association studies. We found more than 100-fold enrichments of the candidates to genetically associated loci with circulating levels of bilirubin and vitamin D, which implicated a link to adverse reactions of PXR ligands. We uncovered novel enhancers of UGT1A1 and TSKU through CRISPR/Cas9 knockout experiments. We identified alleles altering regulatory activities of UGT1A1 and CYP24A1enhancers by using luciferase reporter assay. Furthermore, our siRNA experiments revealed an unexpected impact of TSKU on the expression of vitamin D-metabolizing enzymes. ConclusionsOur transcriptome-based assessment of CREs expanded the list of drug-inducible and PXR-mediated enhancers and super-enhancers. We identified regulatory alleles that alter drug-induced gene expressions, and discovered a novel molecular cascade associated with an adverse reaction. Our results contribute a precise understanding of the noncoding elements of the human genome underlying drug responses.

genomics↗

bioRxiv2024

Familiarity modulates preference for joint feeding with conspecifics in rats

Rats are highly social mammals that form social groups of various sizes. Interestingly, they are known to show prosocial behaviors, and are socially tolerant of other conspecifics as they feed together, but the specificity of their prosociality has not been fully understood. Here, we investigated what degree rats showed social choice, i.e., preferential joint feeding even with unfamiliar animals by performing a simple feeding site choice task. In the task, subjects were tested to choose between the feeding site where they fed with other rats (social option) or the other site where they could feed alone (solitary option). The results showed that social option choices increased particularly when the partner was a single non-cagemate rat. This result means that high social preference for other individuals occurs spontaneously, even when they are feeding with unfamiliar non-cagemates. This high degree of social tolerance would lead to the suppression of aggressive behavior as well as enhancement of affiliative relationships even in situations when the rats met with unfamiliar conspecifics for the first time. HighlightsO_LIRats are highly socially tolerant mammals as they feed with conspecifics together. C_LIO_LIWe explored how the presence of conspecifics affects feeding site choices in rats. C_LIO_LISocial choices increased when the partners were non-cagemates. C_LIO_LISocial choices decreased as the number of non-cagemates increased. C_LIO_LIJoint feeding with a single non-cagemate is observed particularly frequently. C_LI

animal behavior and cognition↗