Ubiquitin C (UbC) is one of the four genes encoding for ubiquitin in the mammalian genome. It has been described as the most responsive gene to cellular treats such as UV irradiation, heat shock, oxidative stress and translational impairment; it was also reported to contribute to maintaining ubiquitin steady state levels under physiological conditions. Despite the bulk of knowledge concerning its function, little is known about the molecular mechanisms modulating UbC expression. Here we review the state of the art of UbC structure, function and transcriptional regulation. Starting from the first evidences which circumscribed the genomic region, pointing out both basic promoter marks (such as transcription start site and TATA-like element), and transcript structure (exonintron boundaries) we go through more detailed molecular studies performed by Marinovic in 2002 and by Bianchi et al. in 2009 and 2013. Herein, the key players orchestrating UbC gene basal activity are underlined.
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