Question

This ion is recruited to both activation loops of a dimer formed when cells detect each other’s ephrins. Pol II’s (“paul two’s”) tail repeatedly reacts with this ion before it initiates transcription. Tau protein reacts with this ion and aggregates into neuro·fibrillary tangles. Binding of this ion controls the activity of the onco·proteins HER2 and Ras (20[1])(“razz”). A 7.4 k·cal bond (20[1])between two of these ions is drawn with a (*) squiggle because it’s so easy to (10[1])break. Serines and tyrosines react (10[1])with this ion to turn on (10[1])each step of the MAPK (“map-K”) pathway. (10[2])Enzymes that transfer this ion (10[2])act as nodes (10[2])in cell signaling cascades and are called (10[3])kinases (10[3])(“KYE-nazes”). For (10[1])10 points, (10[1])three of what ions bond to adenosine (10[2])in the molecule (10[3])that (10[1])cells use to store energy? ■END■ (10[7])

Back to tossups

Buzzes

Summary