Enables translation initiation factor activity. Involved in regulation of translational initiation. Part of eukaryotic translation initiation factor 3 complex. Is expressed in several structures, including Malpighian tubule primordium; anterior endoderm; embryonic/larval midgut primordium; gut section; and somatic trunk mesoderm derivative. Orthologous to human EIF3J (eukaryotic translation initiation factor 3 subunit J).