TRAF1 and infection: Meanwhile, an in vitro experiment also showed that increased TRAF1 expression resulting from the infection of adenovirus-harboring human TRAF1 cDNA (Ad-TRAF1) presented more neuronal apoptosis than decreased TRAF1 expression caused by treatment with TRAF1 short hairpin RNA (Ad-shTRAF1) (Lu et al., 2013).