instruction:
In this task, you are given a sentence. You are expected to recognize the name of gene or protein. Although there might be several correct answers, you need to write one of them.
question:
 We describe a novel and potentially important mechanism of nitric oxide signaling - through direct activation of guanine nucleotide - binding proteins ( G proteins ) .
answer:
G proteins


question:
 Cellularity and fibrosis were unrelated to the presence or absence of oestrogen receptor .
answer:
oestrogen receptor


question:
 Nitric oxide signaling : a possible role for G proteins .
answer:

G proteins