*Review* **Cracking the Monoubiquitin Code of Genetic Diseases**

### **Raj Nayan Sewduth 1,2,**†**, Maria Francesca Baietti 1,2,**† **and Anna A. Sablina 1,2,\***


Received: 7 April 2020; Accepted: 23 April 2020; Published: 25 April 2020

**Abstract:** Ubiquitination is a versatile and dynamic post-translational modification in which single ubiquitin molecules or polyubiquitin chains are attached to target proteins, giving rise to monoor poly-ubiquitination, respectively. The majority of research in the ubiquitin field focused on degradative polyubiquitination, whereas more recent studies uncovered the role of single ubiquitin modification in important physiological processes. Monoubiquitination can modulate the stability, subcellular localization, binding properties, and activity of the target proteins. Understanding the function of monoubiquitination in normal physiology and pathology has important therapeutic implications, as alterations in the monoubiquitin pathway are found in a broad range of genetic diseases. This review highlights a link between monoubiquitin signaling and the pathogenesis of genetic disorders.

**Keywords:** ubiquitin system; genetic diseases; ubiquitin ligase; deubiquitinases; monoubiquitin signaling; vesicular tra fficking; protein complex formation
