There are two different cell lines but molecular biologist do not know that these cell lines have Gs or Gi proteins…

There are two different cell lines but molecular biologist do not know that these cell lines have Gs or Gi proteins, associated with their G-protein coupled receptors. Molecular biologist wants to know about this. Can you design a experiment for him through which he would be able to identify specific Gs or Gi proteins in cell lines? You help will be appreciated.