What is the Origin of Sirtuin Protein Family?

The Sirtuins were first identified in yeast (Sir2) as proteins involved in transcriptional silencing and lifespan extension. The name is an acronym for Silent Information Regulator 2 (Sir2) homologs. Their subsequent discovery in mammals confirmed their broad importance in human health and aging.

What is the Mechanism of Sirtuin Protein Family?

Sirtuins require the cofactor NAD+ for their enzymatic activity, meaning their function is directly coupled to the cell's energy state. They remove acetyl groups from target proteins, including histones and transcription factors, thereby altering gene expression to promote survival and repair under conditions of metabolic stress or caloric restriction. This deacetylation activity is a fundamental mechanism underlying their observed anti-aging and metabolic regulatory effects.

Sirtuin Protein Family ∞ Area

Sirtuin Protein Family

Meaning

The Sirtuin Protein Family, often abbreviated as SIRTs, is a class of NAD+-dependent deacetylase and ADP-ribosyltransferase enzymes that function as critical regulators of cellular metabolism, stress resistance, and DNA repair, playing a central role in longevity pathways. These proteins act as metabolic sensors, linking cellular energy status (NAD+ levels) to gene expression, thereby modulating key processes like mitochondrial function, inflammation, and cellular senescence. There are seven known mammalian sirtuins (SIRT1-SIRT7), each with distinct subcellular localization and functions.