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Tuberous sclerosis complex (TSC) is a genetic disorder with multi-system manifestations and a high burden of disease. In 2013, an international panel of TSC experts revised the guidelines for the diagnosis, surveillance and treatment of the disorder. In South Africa (SA), a local multidisciplinary group of healthcare professionals and TSC researchers reviewed the international guidelines to generate an SA consensus clinical update on the identification, diagnosis, treatment and lifelong monitoring of individuals who live with TSC. We strongly endorse dissemination and use of the international guidelines for the assessment, monitoring and treatment of TSC. In addition, we strongly support access to genetic testing and to mTOR (mammalian target of rapamycin) inhibitors to treat subependymal giant cell astrocytomas not amenable to surgery and renal angiomyolipomas larger than 3 cm, and as adjunctive treatment for refractory focal seizures. We await with interest results from mTOR inhibitor trials of skin and TSC-associated neuropsychiatric disorders (TAND). With regard to training, we recommend the inclusion of TSC in undergraduate and postgraduate medical and health sciences curricula, and the promotion of other continuing professional development events to raise awareness about TSC. We also support the development of a TSC user/carer/parent organisation to provide an informal support network for families across SA. We acknowledge that some progress has been made in recent years in SA, but much remains to be done. We hope that this SA onsensus clinical update based on the international guidelines will make a positive contribution to increase knowledge and improve clinical care for all patients who live with TSC in SA, and their families.

Regulated degradation of proteins by the 26S proteasome plays important roles in maintenance and signalling in eukaryotic cells. Proteins are marked for degradation by the action of E3 ligases that site-specifically modify their substrates by adding chains of ubiquitin. Innate immune signalling in plants is deeply reliant on the ubiquitin-26S proteasome system. While progress has been made in understanding substrate ubiquitination during plant immunity, how these substrates are processed upon arrival at the proteasome remains unclear. Here we show that specific members of the HECT domain-containing family of ubiquitin protein ligases (UPL) play important roles in proteasomal substrate processing during plant immunity. Mutations in UPL1, UPL3 and UPL5 significantly diminished immune responses activated by the immune hormone salicylic acid (SA). In depth analyses of upl3 mutants indicated that these plants were impaired in reprogramming of nearly the entire SA-induced transcriptome and failed to establish immunity against a hemi-biotrophic pathogen. UPL3 was found to physically interact with the regulatory particle of the proteasome and with other ubiquitin-26S proteasome pathway components. In agreement, we demonstrate that UPL3 enabled proteasomes to form polyubiquitin chains, thereby regulating total cellular polyubiquitination levels. Taken together, our findings suggest that proteasome-associated ubiquitin ligase activity of UPL3 promotes proteasomal processivity and is indispensable for development of plant immunity.