All articles tagged with #retrotransposons
Researchers at the Beijing Institute of Genomics identified 159 new avian R2 retrotransposons by scanning 1,139 bird genomes. By engineering these elements, they created an all-RNA system that achieves up to 60% site-specific gene integration in human primary cells, offering a new tool for precise genome editing without double-strand DNA breaks.
Researchers map centromeres across Saccharomycodales and find proto-point centromeres—compact, single Cse4 nucleosomes on AT-rich CDEII with variable flanking motifs—often embedded in Ty5 LTR retrotransposon clusters. Phylogenetic analyses suggest proto-point and point centromeres share an ancient origin and that Ty5 elements provided the genetic substrate for the evolution of genetically defined point centromeres, illustrating how selfish elements can be co-opted for essential chromosome segregation.
A new gene therapy technique called Precise RNA-mediated INsertion of Transgenes (PRINT) leverages retrotransposons found in birds to safely insert genes into a "safe harbor" in the human genome, avoiding disruption of essential genes or potential cancer risks. This approach complements CRISPR-Cas9 gene editing by providing a method to insert whole genes into the genome, offering promise for treating hereditary diseases caused by various mutations in the same gene. The technique involves using a retroelement protein called R2 to efficiently insert genes into the genome, particularly into the ribosomal RNA encoding region, providing a safe and effective method for gene supplementation.
Retrotransposons, a type of transposable element, have been found to hijack a DNA repair pathway called alternative end joining (alt-EJ) to facilitate their own replication and the formation of extrachromosomal circular DNA (eccDNA). Researchers discovered that alt-EJ, which is normally involved in repairing DNA double-strand breaks, is co-opted by retrotransposons to generate the necessary DNA intermediates for their replication. This study sheds light on the mechanisms underlying retrotransposon propagation and eccDNA formation, providing insights into genomic stability and potential implications for diseases such as cancer.