This entry includes hnRNPA1, a nuclear factor that binds to Pol II transcripts. The family of hnRNP proteins are involved in numerous RNA-related activities. hnRNPA1 is involved in the packaging of pre-mRNA into hnRNP particles, transport of poly(A) mRNA from the nucleus to the cytoplasm and modulation of splice site selection. hnRNPA1 plays a role in the splicing of pyruvate kinase PKM by binding repressively to sequences flanking PKM exon 9, inhibiting exon 9 inclusion and resulting in exon 10 inclusion and production of the PKM M2 isoform. This protein binds to the IRES and inhibits the translation of the apoptosis protease activating factor APAF1. During Enterovirus 71 (EV71) infection, APAF1 expression is essential for virus-induced apoptosis and viral particle release. HnRNPA1 has two RNA recognition motifs (RRM1 and RRM2) followed by an unstructured low complexity (LC) C-terminal domain, represented in this entry. This domain can mediate protein-protein and protein-RNA interactions and it is involved in amyloid aggregation, leading to neurodegenerative diseases including amyotrophic lateral sclerosis (ALS) and multisystem proteinopathy (MSP).
Jiyao W et al.(2023). "The conserved domain database in 2023.",