Transcription-dependent nuclear localization of DAZAP1 requires an N-terminal signal

Deleted in Azoospermia Associated Protein 1 (DAZAP1) is a ubiquitous hnRNP protein required for normal development and spermatogenesis. It resides predominantly in the nucleus and moves between the nucleus and the cytoplasm via a ZNS shuttling signal at its C-terminus. DAZAP1 accumulates in the cytoplasm when RNA polymerase II activity is inhibited by actinomycin D. Here we report the mapping of a 42-amino acid segment (N42) at the N-terminus of DAZAP1 that is both necessary and sufficient for its transcription-dependent nuclear localization. In addition, using a yeast two-hybrid system, we have identified SLIRP as a N42-binding protein which may regulate DAZAP1 subcellular localization.

► DAZAP1 shuttles between the nucleus and the cytoplasm.
► DAZAP1 accumulates in the cytoplasm when the nuclear transcription is inhibited.
► DAZAP1’s transcription-dependent nuclear localization requires N-terminal N42.
► SLIRP binds to N42 and may be involved in the process.