MYD88 and infection: To study the pathway by which miR-146 expression is induced in zebrafish embryos upon infection we used embryos in which TLR signalling was disrupted by morpholino knockdown of traf6 or by mutation of myd88. The induction levels of miR-146a and miR-146b upon S. typhimurium infection were reduced under conditions of traf6 or myd88 deficiency, but induction was not completely abolished.