Key component of the 4EHP-GYF2 complex, a multiprotein complex that acts as a repressor of translation initiation. Component of the 4EHP-GYF2 complex (By similarity). Maternally expressed: detected from the 1-cell stage, prior to the onset of zygotic expression. From blastula until gastrula stages, strongly expressed throughout the blastoderm. At 28 hours post-fertilization (hpf), highly expressed in the central nervous system (CNS), whereas a weaker expression is found in the somites. At later stages of development (48 hpf), expression persists in well-defined structures of the CNS, such as the diencephalon, the mesencephalon, the cerebellum and the rhombencephalon, and remains detectable in the somites. Morpholino knockdown show mild, intermediate, and severe phenotypes. Embryos with severe phenotype display a disrupted body pattern, embryos with intermediate phenotype show defects in the head and eye structures, while embryos with mild phenotype only show a twist in the terminal part of the tail. Embryos do not show important cell loss in diencephalic dopaminergic (DA) neuron clusters. Belongs to the GIGYF family.