Acts as one of several non-catalytic accessory components of the cytoplasmic dynein 2 complex (dynein-2 complex), a motor protein complex that drives the movement of cargos along microtubules within cilia and flagella in concert with the intraflagellar transport (IFT) system (PubMed:25205765, PubMed:29742051). DYNC2I2 plays a major role in retrograde ciliary protein trafficking and in ciliogenesis (PubMed:29742051, PubMed:30320547, PubMed:30649997). Required also to maintain a functional transition zone (PubMed:30320547). {ECO:0000269|PubMed:25205765, ECO:0000269|PubMed:29742051, ECO:0000269|PubMed:30320547, ECO:0000269|PubMed:30649997}. Acts as a negative regulator of the Toll-like and IL-1R receptor signaling pathways. Inhibits the MAP3K7-induced NF-kappa-B activation pathway. Inhibits MAP3K7 phosphorylation at 'Thr-184' and 'Thr-187' upon Il-1 beta stimulation. {ECO:0000269|PubMed:19521662, ECO:0000269|PubMed:24183449}. This is the function of Ensembl gene identifier ENSG00000119333 (DYNC2I2, dynein 2 intermediate chain 2).