OCAT 4

1. Economists measure national output with it, but pharmacologists know it as the nucleotide on resting G-alpha. (3 letters)
3. Four letters for the cytosolic, SAM-dependent histamine inactivator. (4 letters)
5. Benzodiazepines at GABA-A receptors are these, boosting agonist effect from a separate site. (28 letters)
6. Intrinsic activity of G-alpha that hydrolyses its bound nucleotide, ending the signal; Ras has it too. (6 letters)
7. Membrane proteins (v- and t-) that twist into a four-helix bundle to pull vesicle and plasma membrane together; also a drummer's tool. (6 letters)
9. A hat on the 5' end: methylated guanosine added to protect pre-mRNA from exonucleases and help ribosomes bind. (7 letters)
11. DAO can't keep up, so flushing and headaches follow red wine and aged cheese: not an allergy, but this. (11 letters)
12. Dideoxynucleotides lack a 3'-OH so the growing ___ can't continue: the ___-termination method. (5 letters)
17. Long-distance calling: glands release signals into the bloodstream to reach far-off targets. (9 letters)
18. The 'IS' in ELISA: antibody-coated wells capture the antigen, so the assay is named for being this. (13 letters)
19. Chemist whose adsorption model of molecules on a surface inspired how drugs bind finite receptor sites. (8 letters)

2. Emptying of stored vesicles when IgE on the surface is crosslinked. (13 letters)
4. Ribosome subunits are labelled 30S, 50S and so on by how fast they settle in the spin: the ___ coefficient. (13 letters)
8. Bert, who shared the 1991 Nobel for the patch clamp with Neher. (7 letters)
10. Seven-pass membrane proteins that are targets of roughly a third of drugs on the market (4 letters). (4 letters)
13. Latin 'within the living': studies in a whole organism. (6 letters)
14. Purine that makes three hydrogen bonds with its partner; also the base in GDP and GTP. (7 letters)
15. The methylated cousin of uracil, found only in DNA and pairing with A through two hydrogen bonds. (7 letters)
16. An allosteric effect can differ with which orthosteric ligand you test it against: the ___ dependence. (5 letters)