Creatine, Creatine Kinase, and Aging.

With an ever aging population, identifying interventions that can alleviate age-related functional declines has become increasingly important. Dietary supplements have taken center stage based on various health claims and have become a multi-million dollar business. One such supplement is creatine, a major contributor to normal cellular physiology.

Identification of a unique Ca-binding site in rat acid-sensing ion channel 3.

Acid-sensing ion channels (ASICs) evolved to sense changes in extracellular acidity with the divalent cation calcium (Ca) as an allosteric modulator and channel blocker. The channel-blocking activity is most apparent in ASIC3, as removing Ca results in channel opening, with the site's location remaining unresolved. Here we show that a ring of rat ASIC3 (rASIC3) glutamates (Glu435), located above the channel gate, modulates proton sensitivity and contributes to the formation of the elusive Ca block site.