Scientists have discovered a new origin story for the key regulatory gene, Polycomb repressive complex 2 (PRC2). Previously thought to primarily control developmental genes, PRC2's ancestral function has been redefined as protecting the genome against transposon invasion. This function, found across various eukaryotes, evolved over time to its current role in silencing protein-coding genes. The study reveals that PRC2 represses transposons in distant lineages of eukaryotes, indicating that this function arose in the ancestor of these lineages. The findings suggest a profound change in paradigm and shed light on the evolutionary history of gene regulation.
Researchers have traced the origins of CRISPR-Cas9, a powerful gene editing tool, to transposons, or "jumping genes," which carry RNA-guided DNA nucleases. By studying the movement of transposons in bacteria, scientists discovered that the DNA-cutting scissors prevent the extinction of transposons by guiding a copy of the transposon back to its original location after cutting the DNA. This "cut and copy" strategy allows transposons to proliferate and spread. The findings suggest that there may be other systems similar to CRISPR-Cas9 waiting to be discovered, which could be used for genome engineering in human cells.
Transposons, a type of mobile genetic element, have been found to encode nucleases that use guide RNAs to promote their own spread. These transposon-encoded nucleases function similarly to the CRISPR-Cas system, allowing them to target and cut specific DNA sequences. This discovery sheds light on the evolutionary relationship between transposons and CRISPR-Cas systems, and highlights the diverse mechanisms by which mobile genetic elements can influence genome editing and horizontal gene transfer in microbial populations.
New research has revealed that transposons, also known as "selfish genes," play important and unexpected roles in biological processes. These jumping genes, which can move within the genome and generate new copies of themselves, make up over 45% of the human genome. While most transposon copies are inactive, a hundred copies belonging to the LINE family are potentially active and contribute to genetic processes. Studies have shown that transposons are essential for the development of the cerebral cortex, embryonic development, and gene regulation. These findings open up new avenues for research and potential treatments for neurodevelopmental and aging-related disorders.
Researchers have discovered that certain roundworms carry a genetic element known as a Maverick, which is capable of transferring genes between species. Mavericks are massive mobile genetic elements that were previously thought to be inactive relics, but this study reveals their ability to mediate horizontal gene transfer. The Maverick in the roundworms contains viral genes and a fusogen protein, suggesting its ability to form virus-like particles and invade different cell types. Further research is needed to observe the Maverick in action and understand its mechanisms. This discovery could have practical applications in controlling parasites that infect agricultural crops and livestock. Additionally, similar massive transposons called Starships have been found in fungi, potentially playing a role in the spread of wheat diseases. Understanding these genetic transfer mechanisms is crucial for comprehending genome evolution.
