Sirtuin shown to control gene activity - Study is first to show such governance, reveals...

Science News ^ | January 8th, 2009 | Tina Hesman Saey

[neverdem]

Study is first to show such governance, reveals protein’s possible anti-aging link

A formerly underappreciated member of the sirtuin family of proteins may hold the key to youthfulness and is the first sirtuin shown to specifically govern the activity of genes, scientists report.

Researchers from Stanford University report in the Jan. 9 Cell that SIRT6, a sibling of the aging-related protein SIRT1, is an important regulator of gene activity in mice.

“This is a big, big discovery,” says Raul Mostoslavsky, a chromatin biologist at the Massachusetts General Hospital Cancer Center and Harvard University Medical School in Boston. And one, he adds, that could shift some of the limelight away from SIRT1, a molecule implicated in the aging process...

--snip--

Last year, Chua’s group showed that SIRT6 is an enzyme that specifically removes a chemical called an acetyl group from a specific spot on a histone protein. Histones wrap DNA into a package that can fit inside the cell and are also important for controlling which genes turn on and off. Removing acetyl groups from histones generally shuts genes off.

Chua’s group has also previously shown that SIRT6 helps keep genomes stable and protects the ends of chromosomes, known as telomeres, from damage.

Now Chua’s and Chang’s groups together show that SIRT6 works with a master regulatory complex called NFkappa-B to govern activity of genes associated with aging, inflammation, immunity and metabolism. When SIRT6 is missing, NFkappa-B becomes hyperactive and turns up activity of aging-linked genes.

Reducing the amount of NFkappa-B in SIRT6-deficient mice restores normal life span and corrects many of the premature aging symptoms. But the mice still have low blood sugar, and many other genes not regulated by NFkappa-B show abnormal activity when SIRT6 is absent...

[neverdem]

SIRT6 Links Histone H3 Lysine 9 Deacetylation to NF-B-Dependent Gene Expression and Organismal Life Span

FReepmail me if you want on or off the diabetes ping list. Click on the keyword sirtuin if you are lost.

[Red Badger]

I don’t want this Sir Tuin controling MY genes!............

[HangnJudge]

/snip
Chua’s group showed that SIRT6 is an enzyme that specifically removes a chemical called an acetyl group from a specific spot on a histone protein. Histones wrap DNA into a package that can fit inside the cell and are also important for controlling which genes turn on and off. Removing acetyl groups from histones generally shuts genes off.

/snip
Mostoslavsky believes many important body systems are affected by SIRT6, but cautions that the enzyme is not necessarily an anti-aging protein. The mutant mice lacking the protein have severe metabolic disturbances that could account for premature aging. Researchers have not yet detected any change in SIRT6 levels or activity with age.

Hmmm...
Interesting, but but exciting, yet