May be a nuclear regulatory protein that is stored in the germinal vesicle for use during early embryogenesis and may play a role in the synthesis or processing of pre-mRNA during oogenesis. Binds 3 Zn(2+) ions. Lampbrush chromosome loops and in some nucleoplasmic particles of the germinal vesicle. It first appears on the chromosome loops and in the nucleoplasm of the germinal vesicle (GV). It is transmitted to the egg at GV breakdown and appears in embryonic nuclei at the mid-blastula stage and is found in many but not all nuclei at still later stages of embryogenesis. B box-type zinc binding domain is required for targeting this protein to lampbrush chromosome loops and for normal functioning of this protein in the oocyte.