It affects many critical genes that are responsible for controlling metabolic pathways at the transcriptional, post-transcriptional, translation, and post-translation levels.

The encoded protein is involved in the packaging of pre-mRNA into hnRNP particles, transport of poly A+ mRNA from the nucleus to the cytoplasm, and may modulate splice site selection.

However, addition of O-GlcNAcylation (GlcNAc) moiety to serine or threonince is a common and reversible modification that impairs the protein's binding of karyopherin beta (Transportin-1) resulting in nuclear localization of hnRNPA1.

hnRNP A1's anti-viral effect is present in human T-cell lymphotropic virus type I (HTLV-1) cell culture model.

hnRNP A1 inhibits the binding of Rex protein to its response element in 3’ long terminal repeat (LTR) of all viral RNAs.

Ectopic expression of hnRNP A1 antagonizes post-transcriptional activity of Rex via competitive binding, eliciting an antiviral response against HTLV-1 infection by negatively affecting the rate of viral replication.

Monette et al. reported increased endogenous expression of hnRNP A1 after HIV-1 infection, as enhanced hnRNPA1 levels were seen as favorable for the virus.

hnRNP A1 antagonizes cellular senescence and induction of the senescence-associated secretory phenotype by stabilizing Oct-4 and sirtuin 1 mRNAs.