MAPT and tauopathy: We investigated the effects of dnj-28 loss of function in xbp-1s-mediated tauopathy suppression in C. elegans by using a putative loss-of-function mutant strain [dnj-28 (ok2490); referred to as dnj-28 (−/−) A] crossed to Tau (high); xbp-1s Tg animals.