Enables ephrin receptor binding activity; eukaryotic initiation factor eIF2 binding activity; and protein domain specific binding activity. Involved in regulation of cellular macromolecule biosynthetic process and regulation of response to endoplasmic reticulum stress. Acts upstream of or within several processes, including ephrin receptor signaling pathway; plasma membrane bounded cell projection assembly; and positive regulation of cellular component organization. Located in cell-cell junction and vesicle membrane. Is expressed in several structures, including extraembryonic component; hemolymphoid system gland; male reproductive gland or organ; nervous system; and somite. Orthologous to human NCK1 (NCK adaptor protein 1). [provided by Alliance of Genome Resources, Apr 2022]