The Role of Transposable Elements in Sexual Development

Abstract

Up to 50% of most mammalian genomes are made up of transposable elements (TEs) that have the potential to mobilize around the genome. Despite this prevalence, research on TEs is only beginning to gain traction within the field of neuroscience. While TEs have long been regarded as “junk” or parasitic DNA, it has become evident that they are adaptive DNA and RNA regulatory elements. In addition to their vital role in normal development, TEs can also interact with steroid receptors, which are key elements to sexual development. In this review, we provide an overview of the involvement of TEs in processes related to sexual development- from TE activity in the germline to TE accumulation in sex chromosomes. Moreover, we highlight sex differences in TE activity and their regulation of genes related to sexual development. Finally, we speculate on the epigenetic mechanisms that may govern TEs’ role in sexual development. In this context, we emphasize the need to further the understanding of sexual development through the lens of TEs including in a variety of organs at different developmental stages, their molecular networks, and evolution.

Analysis of circRNA-miRNA-mRNA regulatory network of embryonic gonadal development in Mulard duck

“…Scholars propose that MORC3 may play a role in gonadal development. Desai et al (2021) found that MORC3 may be involved in chromatin compaction to silence transposable elements ( TEs ), thus regulating gonadal differentiation and gene expression related to gonadal development ( Chiang et al, 2022 ). MORC3 is important for the transcription of P-element-induced wimpy testis ( PIWI )-interacting-RNA ( piRNA ) precursors and subsequently affects piRNA production and that the piRNA pathway plays a crucial role in the suppression of TE by the de novo methylation of DNA in mouse embryonic male germ cells ( Kojima-Kita et al, 2021 ).…”

Epigenetic Gene-Regulatory Loci in Alu Elements Associated with Autism Susceptibility in the Prefrontal Cortex of ASD

“…These observations led Sarachana et al, (2011) to suggest that a decrease in RORA and its transcriptional target aromatase may be related to the reported elevated testosterone in amniotic fluid associated with ASD traits, which has been proposed as a factor influencing the male sex bias in ASD [ 43 ]. Sex differences in TEs in the human genome may be related to the biology of sex differences, such as higher TE density on the Y chromosome, differences in DNA methylation regulators (DNA methyltransferase enzymes and methylcytosine dioxygenases; TET), and histone modification marks [ 44 ]. Another interesting TF is vitamin D receptor (VDR), a nuclear receptor/steroid hormone receptor superfamily.…”