PABPC1PABPC4

PABPC1PABPC4 refers to a human readthrough transcript that is proposed to join the PABPC1 and PABPC4 genes. It has been identified in transcriptome sequencing as a potential readthrough event, where transcription extends from one gene into the neighboring or functionally related gene, producing a chimeric RNA. The coding potential of this transcript is not universally confirmed, and annotations vary regarding whether a functional fusion protein is produced.

Gene and protein context

PABPC1 and PABPC4 encode cytoplasmic poly(A) binding proteins that regulate mRNA stability and translation by binding poly(A) tails and interacting with translation initiation factors. Each protein normally contains RNA recognition motifs and a C-terminal PABC domain that mediates partner interactions. A PABPC1PABPC4 transcript, if translated, is predicted to yield a chimeric protein that could combine domains from both parental PABP family members, potentially altering RNA-binding properties or protein–protein interactions.

Expression and detection

Evidence for PABPC1PABPC4 comes primarily from high-throughput sequencing and targeted assay studies identifying readthrough transcripts. Reported expression appears tissue- or context-dependent and may be of low abundance relative to canonical PABPC1 and PABPC4 transcripts. Validation of a stable, functional protein product remains limited and varies across datasets.

Function and significance

No widely accepted functional role for PABPC1PABPC4 has been established. Given the established roles of PABPC1 and PABPC4 in mRNA metabolism, the fusion transcript or protein could hypothetically influence mRNP assembly, poly(A) tail regulation, or translational control. However, experimental confirmation of its expression, localization, and function is needed.

See also

PABPC1, PABPC4, poly(A) binding protein family, readthrough transcripts.