▁and ▁lip ids . ▁ ▁Ess entially , ▁there ▁is ▁an ▁ 8 3 5 ▁am ino ▁acid ▁N - term inal ▁head , ▁which ▁is ▁split ▁into ▁four ▁domains . ▁This ▁is ▁linked ▁to ▁the ▁C - term inal ▁tail ▁with ▁a ▁linker ▁region . ▁ ▁The ▁recent ▁discovery ▁of ▁the ▁ 3 D ▁structure ▁sh eds ▁light ▁on ▁how ▁this ▁protein ▁tail ors ▁its ▁shape ▁to ▁perform ▁a ▁variety ▁of ▁functions . ▁For ▁example , ▁vin cul in ▁is ▁able ▁to ▁control ▁the ▁cell ’ s ▁mot ility ▁by ▁simply ▁alter ing ▁its ▁shape ▁from ▁active ▁to ▁in active . ▁ ▁When ▁in ▁its ▁‘ in active ’ ▁state , ▁vin cul in ’ s ▁con formation ▁is ▁character ized ▁by ▁the ▁interaction ▁between ▁its ▁head ▁and ▁tail ▁domains . ▁And , ▁when ▁transform ing ▁to ▁the ▁‘ active ’ ▁form , ▁such ▁as ▁when ▁tal in ▁triggers ▁binding , ▁the ▁intr am ole cular ▁interaction ▁between ▁the ▁tail ▁and ▁head ▁is ▁sever ed . ▁In ▁other ▁words , ▁when ▁tal in ’ s ▁binding ▁sites ▁( V BS ) ▁of ▁α - hel ices ▁bind ▁to ▁a ▁hel ical ▁bundle ▁structure ▁in ▁vin cul in ’ s ▁head ▁domain , ▁the ▁‘ hel ical ▁bundle ▁conversion ’ ▁is ▁initi ated , ▁which ▁leads ▁to ▁the ▁re organ ization ▁of ▁the ▁α - hel ices ▁( α 1 - ▁α - 4 ), ▁resulting ▁in ▁an ▁entirely ▁new ▁five - hel ical ▁bundle ▁structure . ▁ ▁This ▁function ▁also ▁extends ▁to