background:
Pausing of elongation complexes is mediated by the transcription termination factor TTF-I bound to the 'Sal box' terminator downstream of the rDNA transcription unit. PTRF is a Pol I and transcript release factor for dissociation of paused ternary complexes.
Function:
Plays an important role in caveolae formation and organization. Required for the sequestration of mobile caveolin into immobile caveolae. Termination of transcription by RNA polymerase I involves pausing of transcription by TTF1, and the dissociation of the transcription complex, releasing pre-rRNA and RNA polymerase I from the template. PTRF is required for dissociation of the ternary transcription complex.
Subunit:
Interacts with RNA polymerase I and TTF1. Binds the 3' end of pre-rRNA. Interacts with transcription factor ZNF148 (By similarity). Interacts with LIPE in the adipocyte cytoplasm.
Subcellular Location:
Cell membrane; caveola (surface). Cell membrane. Microsome. Cytoplasm; cytosol. Mitochondrion. Nucleus. Also found in the plasma membrane, microsomal and cytosolic fractions and at a low level in the mitochondrial and nuclear fractions.
Post-translational modifications:
Phosphorylated. Present in active and inactive forms. Changes in phosphorylation pattern may alter activity (By similarity).
Five truncated forms are found in the caveolae. These are thought to be the result of proteolysis and may be phosphorylation-dependent.
DISEASE:
Defects in PTRF are the cause of congenital generalized lipodystrophy type 4 (CGL4) [MIM:613327]. It is a disorder characterized by the association of congenital generalized lipodystrophy with muscular dystrophy and cardiac anomalies. Congenital generalized lipodystrophy is characterized by a near complete absence of adipose tissue, extreme insulin resistance, hypertriglyceridemia, hepatic steatosis and early onset of diabetes.
Similarity:
Belongs to the PTRF/SDPR family.
Database links:
UniProtKB/Swiss-Prot: Q6NZI2.1
Important Note:
This product as supplied is intended for research use only, not for use in human, therapeutic or diagnostic applications.
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