An ancient ancestor of spiders and relatives doubled its genome about 400 million years ago, setting the stage for the evolution of spinnerets.
A close look at the genetics and development of spinnerets — spiders’ silk-making organs — reveals that an early arachnid doubled all of its DNA hundreds of millions of years ago. The findings, published January 14 inhave remained elusive, says Shuqiang Li, an evolutionary developmental biologist at Anhui Normal University in Wuhu, China.
One hypothesis was that spinnerets could have formed in the wake of a duplication of limb-patterning genes.Li and his team analyzed the full genetic instruction books of two spider species and a whip scorpion, a clawed arachnid with a thin tail. They compared these genomes to those of other arachnid groups and found evidence that around 400 million years ago, an early ancestor of the group that gave rise to spiders, scorpions and whip scorpions experienced a massive mutation that duplicated its entire genome. This single event led to extra copies of genes all over the arachnids’ genomes., which — through a series of genetic and developmental experiments on spider embryos — Li and his colleagues determined was heavily involved in the formation of spinnerets from protolimbs. Inactivating the gene made embryos lose their spinnerets. Each gene copy appears to have evolved different roles after the duplication, working together to create spinnerets. “The genomic work is beautiful,” says invertebrate biologist Prashant Sharma at the University of Wisconsin–Madison, but he doesn’t think the study has totally ruled out another explanation for spinnerets’ origins. Other arthropods such asgene and have conspicuously truncated bodies with missing rear body parts. It may be that the genes govern the entire rear body segments instead of the spinnerets specifically. The researchers may have instead stumbled upon a genetic route to making a sea spider-like or mitelike animal, Sharma says. Whole genome duplication is common in plant evolution, but rarer among animals. The process may create a massive upswing in genomic real estate and opportunity to evolve new gene interactions. It has been associated with major evolutionary changes, like boosting the diversity of jawed vertebrate body plans.
United States Latest News, United States Headlines
Similar News:You can also read news stories similar to this one that we have collected from other news sources.
The 8 Worst Franchise KillersAndrew Garfield in The Amazing Spider-Man 2
Read more »
Animal Care Services receives nearly 400 cold-related calls amid weather eventSAN ANTONIO — Animal Care Services leadSince the start of the weather event, ACS says they’ve received more than 900 calls for service with nearly 400 related t
Read more »
Spider-Man’s 10 Best Team-Ups in Marvel ComicsSpider-Man has been in lots of fantastic team-ups over his career in comics, and here are his best partners along the way.
Read more »
Nearly 400 PA National Guard members on standby to assist with winter storm impactsThe Pennsylvania National Guard (PANG) activated over 375 members ahead of the winter storm, and they're standing by to assist at multiple locations across PA.
Read more »
Spider-Man: Brand New Day to Feature Even More Unannounced VillainsSpider-Man: Brand New Day is already packed with new and returning Marvel characters, but more villains are reportedly joining the movie.
Read more »
Bruce Banner Becomes the Cosmic Hulk: 'Too Powerful for His Own Good'mcu's smart hulk and a big hulk eye and spider-man
Read more »