This family consists of several conserved novel zinc finger domains found in the eukaryotic proteins Nanos and Xcat-2. In Drosophila melanogaster, Nanos functions as a localised determinant of posterior pattern. Nanos RNA is localised to the posterior pole of the maturing egg cell and encodes a protein that emanates from this localised source. Nanos acts as a translational repressor and thereby establishes a gradient of the morphogen Hunchback [1]. Xcat-2 is found in the vegetal cortical region and is inherited by the vegetal blasomeres during development, and is degraded very early in development. The localised and maternally restricted expression of Xcat-2 RNA suggests a role for its protein in setting up regional differences in gene expression that occur early in development [2].

1: nanos is an evolutionarily conserved organizer of anterior-posterior polarity. Curtis D, Apfeld J, Lehmann R; Development 1995;121:1899-1910. PMID:7601003

2: A mRNA localized to the vegetal cortex of Xenopus oocytes encodes a protein with a nanos-like zinc finger domain. Mosquera L, Forristall C, Zhou Y, King ML; Development 1993;117:377-386. PMID:8223259

3: Nanos Plays a Conserved Role in Axial Patterning outside of the Diptera. Lall S, Ludwig MZ, Patel NH; Curr Biol 2003;13:224-229. PMID:12573218