The nuclear pore protein NUP62 localizes to spindle poles in mitosis and plays a role in maintaining centrosome homeostasis. In this study, we found that NUP62-depleted cells exhibited a defective spindle assembly checkpoint (SAC) and that depletion of NUP62 caused a slight decrease in MAD2 protein levels after nocodazole treatment. However, depletion of NUP62 did not cause a failure in kinetochore localization of the SAC proteins BUBR1, MAD1, and MAD2 in prometaphase. NUP62 depletion slightly prolonged mitotic timing but did not affect cell doubling time. In addition, NUP62 depletion caused a SAC defect and induced aneuploidy in human neural stem cells. Furthermore, overexpression of NUP62Q391P, a mutant protein causing autosomal recessive infantile bilateral striatal necrosis, resulted in a defect in the SAC, indicating that the amino acid residue Q391 in NUP62 is crucial for its effect on the SAC. Overall, we conclude that NUP62 maintains the SAC downstream of kinetochores and thereby ensures maintenance of chromosomal stability.

Prompted by findings suggesting immune instability in infantile bilateral striatal necrosis (IBSN), we evaluated levels of proinflammatory (tumor necrosis factor α, interleukin [IL]-1β, IL-6, interferon [IFN]γ) and anti-inflammatory (IL-10 and IL-1ra) cytokines produced by peripheral blood mononuclear cells (PBMC) from 6 children with IBSN and 11 age-matched controls. Compared to controls, non-stimulated PBMC from the IBSN group produced a significantly lower level of IL-1ra (by 38%; p < 0.001) and significantly lower levels of TNFα, IL-1β, and IFNγ (by 36% [p < 0.001], 25% [p = 0.06], and 32% [p < 0.02]) under PBMC stimulation. The severe cachexia manifesting shortly after IBSN onset may impair the immunological state, placing patients at risk of death from hyperpyrexia and sepsis.

Abnormal concentrations of dopamine and serotonin metabolites in the cerebrospinal fluid is the diagnostic hallmark of a group of treatable conditions known as the monoamine neurotransmitter disorders. We assessed cerebrospinal fluid dopamine and serotonin metabolite concentrations in a series of 69 patients affected by movement disorders of unknown etiology. Abnormal results were disclosed in 13/69 subjects (19%). Both primary and secondary monoamine neurotransmitter disorders were observed. The clinical presentation of both forms was hypokinetic-rigid syndrome or dystonia. L-Dopa treatment resulted in significant improvement of the clinical picture in the majority of primary neurotransmitter disorders. Eight patients presented a secondary neurotransmitter disorder. One suffered from a GM2 gangliosidosis and one from infantile bilateral striatal necrosis. Etiologic diagnoses were not established in the others. L-Dopa was started in four patients, leading to a significant improvement of hypokinesia in the patient suffering from GM2 gangliosidosis and a slight improvement in 3 unclassified patients.