From Newsgroup: talk.origins

https://phys.org/news/2025-12-discovery-intron-rich-eukaryotic-genome.html

https://academic.oup.com/dnaresearch/advance-article/doi/10.1093/dnares/dsaf035/8348290

This organism is touted as a eukaryote with the most intron rich genome.
It's nuclear genome is 214 million base pairs with 17,500 protein
genes, but introns in those genes account for 74% of the genomic
sequence. It's coding sequence is packed with noncoding exons. They
claim that these are spliceosomal introns and not self splicing
transposable parasitic introns. So this lineage went nuts in when it
came to introducing introns into coding sequence. For humans more than
half of the 3 billion base-pair genome is made up of repetitive sequence
or transposable elements that can still be identified as being
transposons. Most of the rest is likely old transposon sequence that
has degenerated past recognition. Less than 2% of the human genome is
coding sequence (exons) and introns within those genes account for
around 25% of the genome. Introns can be composed of a lot of different sequence origins like basically random sequence, transposons or
pseudogene insertions. There are even other coding genes contained
within some of the larger introns. My guess is that this critter's
introns are just as complex.

Amoebiformis has 4 genomes (1 nuclear and 3 organellar genomes). One of
it's organellar genomes is derived from a eukaryotic algae and the other
two are of bacterial origin. For some reason it is transferring
mitochondrial sequence to it's nuclear genome, but has not done that for
the plastid genomes.

This is a strange little beasty.

Ron Okimoto

--- Synchronet 3.21a-Linux NewsLink 1.2