Spatial and temporal control of mRNA localization and translation plays critical roles in many events during germ cell development and asymmetric body pattern formation.Aberrant mRNA localization and untimely protein synthesis during oogenesis can lead to defect and mis-patterning of germ cell formation,causing embryonic lethality and sterility.We focus on the structural and functional studies of important protein-RNA interactions that direct Drosophila oocyte development,with particular emphases on molecular mechanisms of localization and translational control of key mRNAs.We have solved several crystal structures of these protein-RNA complexes,suggesting possible functions of protein factors in the regulation of translation of relevant mRNAs,and providing structural insights into novel protein-RNA interaction motifs involving hydrolase-related and WD40-like domains.