The solar system’s neglected stepchild until recently, the planet has now been scrutinized twice at close range by the MESSENGER spacecraft. The craft’s most recent flyby, on October 6, 2008, has ...

A new study describes the development of a cAMP analogue that specifically activates only Epac2, one of several cAMP-responsive proteins. Furthermore, the analogue activates Epac2 more potently than ...

Little more than three weeks after MESSENGER’s first historic flyby of Mercury, the team this week began mapping out its trajectory and observation plans for the probe’s second pass of the planet this ...

Scientists have uncovered a novel pathway by which hormones elevated in inflammation, cancer and cell injury act on cells to stimulate their growth. Many intracellular signaling proteins work as ...

Extracellular stimuli elicit cellular responses through generation of intracellular second messengers. The lipid second messenger diacylglycerol is produced following activation of the ...

NASA’s MErcury Surface, Space ENvironment, GEochemistry, and Ranging (MESSENGER) spacecraft swung by Venus for the second time early this evening for a gravity assist that shrank the radius of its ...