In {TAIL ~ yeast}, {HEAD ~ SIR2} is required for transcriptional silencing , and is also involved in suppressing rDNA recombination and controlling life span  
In { TAIL ~ yeast } , { HEAD ~ SIR2 } is required for transcriptional silencing , and is also involved in suppressing rDNA recombination and controlling life span
REL TAIL TAIL TAIL TAIL TAIL OTH HEAD HEAD HEAD HEAD HEAD OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH OTH