Involved in postimplantation and gastrulation stages of development. Binds to DNA and RNA. Involved in the nucleocytoplasmic shuttling of STAU2 (By similarity). Found in a cytoplasmic mRNP complex with STAU2. Does not interact with STAU1 (By similarity). Interacts with STAU2. Associated with chromosome foci in meiotic cells. Localizes in somatodendritic compartment of primary hippocampal neurons (By similarity). Colocalizes with STAU2 in several cytosolic RNA granules (By similarity). Associated with chromosomes. Expressed in Sertoli cells, spermatocytes, primary and growing oocytes and granulosa cells (at protein level). Expressed in testis, ovary and brain. Expressed in embryos at 5.5, 6.5 and 7 dpc (at protein level). Expressed in the trophoectoderm cells and inner cell mass of blastocysts (at protein level). Knockout mice form mesoderm but are delayed in their development and fail to form normal anterior embryonic structures. They show both an increase in programmed cell death and a decrease in mitotic index, especially in the region of the distal tip of the embryonic ectoderm. They also show a reduction in apical vacuoles in the columnar visceral endoderm cells in the extraembryonic region. Knockout mice die by 8 to 9 days of gestation. Truncated N-terminus. Contaminating sequence. Potential poly-A sequence. Truncated N-terminus. Contaminating sequence. Potential poly-A sequence.