text: Yo, check it out, I'm 'bout to drop some knowledge,
  'Bout them G(1) cyclins, let's get to college.
  In budding yeast, Cdc28p, that's the kinase,
  Gets its specificity from cyclins, no mistake.
  
  Cln3p, G(1) cyclin, nucleus is its place,
  Cln2p chills in the cytoplasm, that's its space.
  They bind to Cdc28p, that's the connection,
  Phosphorylation in Cln2p for nuclear depletion.
  
  Energy-dependent process, that's how it goes,
  No RAN GTPase, that's what the research shows.
  Phosphorylation's weak in those newborn cells,
  Less depletion in the nucleus, that's what it tells.
  
  Cln2p's got a short stay in the nucleus, you see,
  Early in the cell cycle, that's where it wants to be.
  But Cln3p, its localization's not affected,
  Nuclear localization signal, that's the method.
  
  At the C terminus, that's where it's found,
  Nuclear localization for Cln3p can be bound.
  Green fluorescent protein, it can do the same,
  RAN-dependent, that's how it gains its fame.
  
  Mislocalized Cln3p, without the NLS,
  Less active in Cln3p assays, I confess.
  But more active in Cln2p assays, that's the key,
  Cln3p's localization, that's its specialty.