Nucleolar ribosomal RNA synthesis continues in differentiating lens fiber cells until abrupt nuclear degradation required for ocular lens transparency.

ABSTRACT: Cellular differentiation requires highly coordinated action of all three transcriptional systems to produce rRNAs, mRNAs and various 'short' and 'long' non-coding RNAs by RNA Polymerase I, II and III systems, respectively. RNA Polymerase I catalyzes transcription of about 400 copies of mammalian rDNA genes, generating 18S, 5.8S and 28S rRNA molecules. Lens fiber cell differentiation is a unique process to study transcriptional mechanisms of individual crystallin genes as their very high transcriptional outputs are directly comparable only to globin genes in erythrocytes. Importantly, both terminally differentiated lens fiber cells and mammalian erythrocytes degrade their nuclei through different mechanisms. In lens, the generation of the organelle-free zone (OFZ) includes the degradation o

SUBMITTER: Rayee D 

PROVIDER: S-EPMC11959900 | biostudies-literature | 2025 Dec

REPOSITORIES: biostudies-literature