ALYREF links 3'-end processing to nuclear export of non-polyadenylated mRNAs

The RNA-binding protein ALYREF plays key roles in nuclear export and also 3'-end processing of polyadenylated mRNAs, but whether such regulation also extends to non-polyadenylated RNAs is unknown. Replication-dependent (RD)-histone mRNAs are not polyadenylated, but instead end in a stem-loop (SL) structure. Here, we demonstrate that ALYREF prevalently binds a region next to the SL on RD-histone mRNAs. SL-binding protein (SLBP) directly interacts with ALYREF and promotes its recruitment. ALYREF promotes histone pre-mRNA 3'-end processing by facilitating U7-snRNP recruitment through physical interaction with the U7-snRNP-specific component Lsm11. Furthermore, ALYREF, together with other components of the TREX complex, enhances histone mRNA export. Moreover, we show that 3'-end processing promotes ALYREF recruitment and histone mRNA export. Together, our results point to an important role of ALYREF in coordinating 3'-end processing and nuclear export of non-polyadenylated mRNAs.

Source: EMBO Journal - April 24, 2019 Category: Molecular Biology Authors: Fan, J., Wang, K., Du, X., Wang, J., Chen, S., Wang, Y., Shi, M., Zhang, L., Wu, X., Zheng, D., Wang, C., Wang, L., Tian, B., Li, G., Zhou, Y., Cheng, H. Tags: RNA Biology Articles Source Type: research