Answering the Cell Stress Call: Satellite Non-Coding Transcription as a Response Mechanism

Abstract

Organisms are often subjected to conditions that promote cellular stress. Cell responses to stress include the activation of pathways to defend against and recover from the stress, or the initiation of programmed cell death to eliminate the damaged cells. One of the processes that can be triggered under stress is the transcription and variation in the number of copies of satellite DNA sequences (satDNA), which are involved in response mechanisms. Satellite DNAs are highly repetitive tandem sequences, mainly located in the centromeric and pericentromeric regions of eukaryotic chromosomes, where they form the constitutive heterochromatin. Satellite non-coding RNAs (satncRNAs) are important regulators of cell processes, and their deregulation has been associated with disease. Also, these transcripts have been associated with stress-response mechanisms in varied eukaryotic species. This review intends to explore the role of satncRNAs when cells are subjected to adverse conditions. Studying satDNA transcription under various stress conditions and deepening our understanding of where and how these sequences are involved could be a key factor in uncovering important facts about the functions of these sequences.

More than the SRY: The Non-Coding Landscape of the Y Chromosome and Its Importance in Human Disease

“…This section is characterized by the pentanucleotide repeat TTCCA, and while the human satellite III sequences occur on chromosome 1 and 9's heterochromatin and chromosomes 13-15, 22, there is no cross-reaction between the chromosomes, indicating the sequences are unique, albeit interspersed with the TTCCA repeats [40,41]. Human Satellite III has also been shown to express various transcripts, specifically in response to stress, indicating its transcription potential, even though it is comprised of heterochromatin [42][43][44][45]. This theoretical and yet also very real enigma that surrounds the sequence of the human Y chromosome creates an adverse environment for identifying the genetic differences between males and females.…”