HNRNPL
Domain
RRM domain 2 has moderate RNA-binding affinity. RRM domains 3 and 4 may facilitate RNA looping when binding to two appropriately separated binding sites within the same target pre-mRNA (PubMed:23782695).
Function
Splicing factor binding to exonic or intronic sites and acting as either an activator or repressor of exon inclusion. Exhibits a binding preference for CA-rich elements (PubMed:11809897, PubMed:22570490, PubMed:24164894, PubMed:25623890, PubMed:26051023). Component of the heterogeneous nuclear ribonucleoprotein (hnRNP) complexes and associated with most nascent transcripts (PubMed:2687284). Associates, together with APEX1, to the negative calcium responsive element (nCaRE) B2 of the APEX2 promoter (PubMed:11809897). As part of a ribonucleoprotein complex composed at least of ZNF827, HNRNPK and the circular RNA circZNF827 that nucleates the complex on chromatin, may negatively regulate the transcription of genes involved in neuronal differentiation (PubMed:33174841). Regulates alternative splicing of a core group of genes involved in neuronal differentiation, likely by mediating H3K36me3-coupled transcription elongation and co-transcriptional RNA processing via interaction with CHD8.
Post-translational modifications
Several isoelectric forms of the L protein are probably the results of post-translational modifications.
Phosphorylation at Ser-544 by CaMK4 enhances interaction with a CaMK4-responsive RNA element (CaRRE1), and prevents inclusion of the stress axis-regulated exon (STREX) of the KCNMA1 potassium channel transcripts upon membrane depolarization.
Cellular localization
- Nucleus
- Nucleoplasm
- Cytoplasm
- Localized in cytoplasmic mRNP granules containing untranslated mRNAs. These granules are not identical with P bodies or stress granules.
Alternative names
HNRPL, P/OKcl.14, HNRNPL, Heterogeneous nuclear ribonucleoprotein L, hnRNP L