KHSRP combines transcriptional and posttranscriptional mechanisms to regulate monocytic differentiation.

Abstract

RNA-binding proteins (RBPs) are widely involved in the transcriptional and posttranscriptional regulation of multiple biological processes. The transcriptional regulatory ability of RBPs was indicated by the identification of chromatin-enriched RBPs (Che-RBPs). One of these proteins, KH-type splicing regulatory protein (KHSRP), is a multifunctional RBP that has been implicated in mRNA decay, alternative splicing, and miRNA biogenesis and plays an essential role in myeloid differentiation by facilitating the maturation of miR-129. In this study, we revealed that KHSRP regulates monocytic differentiation by regulating gene transcription and RNA splicing. KHSRP-occupied specific genomic sites in promoter and enhancer regions to regulate the expression of several hematopoietic genes through transcriptional activation and bound to pre-mRNA intronic regions to modulate alternative splicing during monocytic differentiation. Of note, KHSRP had co-regulatory effects at both the transcriptional and posttranscriptional levels on MOGOH and ADARB1. Taken together, our analyses revealed the dual DNA- and RNA-binding activities of KHSRP and have provided a paradigm to guide the analysis of other functional Che-RBPs in different biological systems.