All articles tagged with #genome evolution
About 8% of the human genome is derived from ancient retroviruses; some of these viral sequences, notably the syncytin genes, have been repurposed to drive placental formation, with decisive knockout data in mice and strong but inferential evidence in humans; across mammals, multiple independent viral captures suggest placental evolution repeatedly borrowed viral tools rather than a single origin.
Researchers show that the clonal Amazon molly uses gene conversion to sustain natural selection: it creates new clonal lineages by reverting or fixing mutations and resolves incompatibilities between parental haplotypes, slowing degenerative mutation accumulation (Muller’s ratchet) while preserving parental divergence and altering chromatin organization in the transition to clonality.
The study reveals that independent terrestrialization events in animals involved convergent genomic adaptations, including gene gains and losses related to osmoregulation, stress response, immunity, and sensory functions, with three major temporal windows identified during Earth's history, highlighting both predictable and lineage-specific evolutionary responses to land colonization.
Bryophytes possess a larger and more diverse gene family space than vascular plants, driven by extensive gene formation, horizontal gene transfer, and de novo gene origination, which likely contributed to their ecological adaptability and long-term survival on land.
The study investigates the genomic basis of the unique body plan of chaetognaths, revealing extensive gene loss, tandem gene duplications, and a large Hox gene expansion, alongside the evolution of novel cell types and gene regulation strategies like trans-splicing, which together underpin their distinctive morphology and complex sensory systems.
A recent study uncovers how the 'jumping gene' LINE-1 hijacks cell division processes by forming condensates with proteins to enter the nucleus and copy itself, providing insights into genome evolution and potential therapeutic targets.
A study reports a high-quality reference genome sequence for the western clawed frog, Xenopus tropicalis, along with draft chromosome-scale sequences of three distantly related emerging model frog species, revealing that frog chromosomes have remained remarkably stable since the Mesozoic Era with limited translocations and fusions. The study explores the structure of chromosomes across frogs, using a dense meiotic linkage map for X. tropicalis and chromatin conformation capture (Hi-C) data for all species, revealing conserved ancestral anuran chromosomes from which contemporary frog genomes were constructed. The findings provide essential resources for further work to exploit the experimental possibilities of these diverse animals and make anurans ripe for comparative genomic and evolutionary analysis.
Researchers have reported the X-ray and cryoelectron-microscopy structures of the machinery that enables LINE-1 (L1) DNA elements to self-duplicate and spread throughout mammalian genomes, shedding light on the process of chromosome evolution. This biological 'copy and paste' mechanism provides insight into how and where this DNA element is duplicated, offering valuable information for understanding genome evolution and molecular biology.