For example, {HEAD ~ general, well defined promoter sequences} of {TAIL ~ chicken} β actin and C. elegans ribosomal genes have successfully directed expression of GFP in hydra  
For example , { HEAD ~ general , well defined promoter sequences } of { TAIL ~ chicken } β actin and C. elegans ribosomal genes have successfully directed expression of GFP in hydra
OTH OTH OTH HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD HEAD REL TAIL TAIL TAIL TAIL TAIL OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH