Isoform 1 and isoform 2 may play a role in spermatid differentiation. Isoform 1 and isoform 2 regulate thymus function by modulating stromal cell proliferation via interference with the NEDD8 pathway. Interacts with KIF17. Interacts with UBA3. Located throughout the cytosol of early round spermatids. By the end stages of round spermatid development, concentrated at the side of the cell near the nascent flagellum and in the manchette. In mature sperm, located in the principle piece of the tail. Located throughout the cytosol of early round spermatids. By the end stages of round spermatid development, concentrated at the side of the cell near the nascent flagellum and in the manchette. In mature sperm, located in the principle piece of the tail. Expressed in the subcapsular region of the thymus and lymph node (at protein level). Highly expressed in thymic cortical stromal cells and testis. Lower levels found in brain cortex, hippocampus, kidney, cerebellum, skeletal muscle, epididymis and ovary. No expression detected in other lymphoid organs including bone marrow and spleen. Isoform 1 and isoform 2 are expressed predominantly in testis. Isoform 3, isoform 4 and isoform 5 are expressed predominantly in thymus although isoform 3 is also expressed in testis. In the CNS, highly expressed in restricted areas, the cerebellum and hippocampus. In testis, isoform 1 and isoform 2 are expressed only in the adult from postnatal week 7. Expression is detected in pachytene spermatocytes, increases greatly in round spermatids and is very strong in round/elongating and elongating spermatids. Expression is reduced in condensed spermatids and persists in spermatozoa. Isoform 3 is specifically expressed in round spermatids and is greatly reduced in spermatids under maturation (at protein level). Isoform 7 is detected in the embryo from day 10 while isoform 7 is not detected until day 12. In brain, predominantly expressed by granule cells during cerebellar development. Isoform 1 and isoform 3 are differentially expressed during cerebellar development. Up-regulated in aged mice (4 months of age or older). Belongs to the TBATA family. Extended N-terminus. Extended N-terminus.