| Modification Notes |
Ribosomal 5S RNA (5S rRNA) exists as part of a larger ribosomal subunit and is thought to stabilize ribosome structure, thereby helping protein synthesis. GTF3A (general transcription factor IIIA) is also known as Factor A, AP2 or TFIIIA (transcription factor IIIA) and is a 365 amino acid protein that is localized to the nucleus and is primarily expressed in brain and ovary. GTF3A is a Pol III transcription factor that binds to the internal control region of 5S RNA genes in order to regulate their expression. After GTF3A binds to the internal control region of the 5S RNA gene, the transcription initiation complex is able to form. GTF3A is also a transcript chaperone for 5S RNA to be moved to the cytoplasm where it is stored as a GTF3A-5S RNA complex, which is known as a 7S ribonucleoprotein. GTF3A possesses nine C2H2-type zinc fingers and has a C-terminal region without zinc fingers. The multiple zinc finger configuration of GTF3A allows it to bind to DNA at many locations along the internal control region, and is thought to be important for GTF3A to stay bound to DNA while facilitating many rounds of transcription. |
