Having effortlessly transitioned into acting, Fouzia's debut film swiftly captured global acclaim, earning accolades at the prestigious Cannes Film Festival
A single gene appears to be in charge, preventing additional tooth formation in species destined for a limited set. When the scientists bred mice that lacked that gene, the rodents developed extra teeth next to their first molars — backups like sharks and other non-mammals grow, University of Rochester scientists reported Thursday.
If wondering about shark teeth seems rather wonky, consider: Tooth loss from gum disease is a major problem, here and abroad, and dentures or dental implants are far from perfect treatments. If scientists knew exactly what triggers a new tooth to grow in the first place, it's possible they could switch that early-in-life process on again during adulthood to regenerate teeth.
"It's exciting. We've got a clue what to do," said Dr. Songtao Shi of the University of Southern California School of Dentistry, who said the Rochester discovery will help his own research into how to grow a new tooth from scratch.
Also intriguing: All the mice born without this gene, called Osr2, had cleft palates severe enough to kill. So better understanding of this gene might play a role in efforts to prevent that birth defect, the Rochester team reported in the journal Science.
Teeth may not be visible until long after birth, but they start to form early in embryo development. Teeth ultimately erupt from a thickened band of tissue along the jaw line called the dental lamina, a band that forms in a top layer of the gum called the epithelium. Scientists have long thought the signals for tooth formation must lie in that tissue layer as well.
Not so, the Rochester team found: All the action takes place instead in a deeper cell layer called the mesenchyme.
Think of the Osr2 gene as a control switch, a kind of gene that turns on and off the downstream actions of other genes and proteins. In that mesenchymal tissue, the Osr2 gene works in concert with two other genes to make sure budding teeth form in the right spot, said lead researcher Dr. Rulang Jiang, a geneticist at Rochester's Center for Oral Biology.
"It's almost a self-generating propagation of the signal" that leads to one tooth after another forming all in a row, he explained.
Knocking that molecular pathway out of whack causes either missing or extra teeth to result, Jiang showed in a series of mouse experiments.
Having effortlessly transitioned into acting, Fouzia's debut film swiftly captured global acclaim, earning accolades at the prestigious Cannes Film Festival
Parag, who reached his 50 off 34 balls, cracked 25 runs with three fours and two sixes off the final over bowled by star South Africa paceman Anrich Nortje
Fans were left scratching their heads when Mumbai opted to take Bumrah out of the attack after he bowled the fourth over
With the help of modern equipment, manicured golf courses and elite athletes the scores are getting lower and the game becoming even more captivating
With 10 matches remaining Arsenal lead a three-way title race having won eight successive games
Three separate Israeli strikes on Wednesday, including on a health centre in the border village of Habariyeh, killed 11 civilians
Netanyahu tries to soothe a rift with Biden as he plans to send a government delegation to Washington after earlier cancelling the trip
Among the 24 horses Japan has sent to Dubai is impressive Riyadh Dirt Sprint winner Remake who eyes a Middle East double