Johbu Itoh

1 Introduction Liquid–liquid phase separation (LLPS) is increasingly recognized as a fundamental mechanism for intracellular compartmentalization and regulation of biological processes, including transcription, translation, and signal transduction (Anderson and Kedersha 2009; Brangwynne, et al. 2011; Brangwynne 2013; Dolgin 2018; Feng et al. 2019; Lee, et al. 2014; Li, et al. 2012; Li et al. 2022; Boeynaems et al. 2018; Molliex et al. 2015; Nott et al. 2015; Olzmann and Carvalho 2019; Peng et al.

Abstract RTL4, a gene acquired from a retrovirus, is a causative gene in autism spectrum disorder. Its KO mice exhibit increased impulsivity, impaired short-term spatial memory, failure to adapt to novel environments, and delayed noradrenaline (NA) recovery in the frontal cortex. However, due to its very low expression in the brain, it remains unknown which brain cells express RTL4 and its dynamics in relation to NA.

1. Introduction Retrotransposon Gag-like (RTL, also known as sushi-ichi retrotransposon homolog (SIRH)) genes are eutherian-specific except for therian-specific Paternally expressed 10 (PEG10) [1,2,3,4,5]; comparative genome analyses have provided convincing evidence that PEG10 emerged in a therian common ancestor while others are conserved exclusively in eutherians [5,6,7], indicating that they are presumably derived from an extinct retrovirus similar to the sushi-ichi retrotransposon.