Cardiovascular Disease in Patients With Systemic Lupus Erythematosus: Potential for Improved Primary Prevention With Statins.

Cardiovascular disease (CVD) is a significant cause of morbidity and mortality in patients with systemic lupus erythematosus (SLE). This is especially true in SLE patients with traditional CVD risk factors (eg, hypertension, hyperlipidemia, obesity) and disease-related risk factors (eg, increased SLE disease activity, elevated C-reactive protein levels, and antiphospholipid antibodies). The only guidelines in the primary prevention of CVD in SLE patients involve reducing traditional risk factors, but there are additional therapies that may be beneficial, including statin use. Current data on statin use for prevention of CVD in SLE patients are limited, but there have been some promising results. Statin use has been shown to be especially important in SLE patients for decreasing low-density lipoprotein levels and preventing CVD in hyperlipidemic patients. In addition, there is evidence suggesting that it may be beneficial to use statins in SLE patients with chronically elevated high-sensitivity C-reactive protein levels and antiphospholipid antibodies. It is important to continue to investigate the impact of statins on CVD in SLE patients, as they could significantly improve outcomes in patients with this disease.

A Genome-wide CRISPR Death Screen Identifies Genes Essential for Oxidative Phosphorylation.

Oxidative phosphorylation (OXPHOS) is the major pathway for ATP production in humans. Deficiencies in OXPHOS can arise from mutations in either mitochondrial or nuclear genomes and comprise the largest collection of inborn errors of metabolism. At present we lack a complete catalog of human genes and pathways essential for OXPHOS. Here we introduce a genome-wide CRISPR "death screen" that actively selects dying cells to reveal human genes required for OXPHOS, inspired by the classic observation that human cells deficient in OXPHOS survive in glucose but die in galactose. We report 191 high-confidence hits essential for OXPHOS, including 72 underlying known OXPHOS diseases. Our screen reveals a functional module consisting of NGRN, WBSCR16, RPUSD3, RPUSD4, TRUB2, and FASTKD2 that regulates the mitochondrial 16S rRNA and intra-mitochondrial translation. Our work yields a rich catalog of genes required for OXPHOS and, more generally, demonstrates the power of death screening for functional genomic analysis.

Disulfide-mediated stabilization of the IκB kinase binding domain of NF-κB essential modulator (NEMO).

Human NEMO (NF-κB essential modulator) is a 419 residue scaffolding protein that, together with catalytic subunits IKKα and IKKß, forms the IκB kinase (IKK) complex, a key regulator of NF-κB pathway signaling. NEMO is an elongated homodimer comprising mostly α-helix. It has been shown that a NEMO fragment spanning residues 44-111, which contains the IKKα/ß binding site, is structurally disordered in the absence of bound IKKß. Herein we show that enforcing dimerization of NEMO1-120 or NEMO44-111 constructs through introduction of one or two interchain disulfide bonds, through oxidation of the native Cys54 residue and/or at position 107 through a Leu107Cys mutation, induces a stable α-helical coiled-coil structure that is preorganized to bind IKKß with high affinity. Chemical and thermal denaturation studies showed that, in the context of a covalent dimer, the ordered structure was stabilized relative to the denatured state by up to 3 kcal/mol. A full-length NEMO-L107C protein formed covalent dimers upon treatment of mammalian cells with H2O2. Furthermore, NEMO-L107C bound endogenous IKKß in A293T cells, reconstituted TNF-induced NF-κB signaling in NEMO-deficient cells, and interacted with TRAF6. Our results indicate that the IKKß binding domain of NEMO possesses an ordered structure in the unbound state, provided that it is constrained within a dimer as is the case in the constitutively dimeric full-length NEMO protein. The stability of the NEMO coiled coil is maintained by strong interhelix interactions in the region centered on residue 54. The disulfide-linked constructs we describe herein may be useful for crystallization of NEMO's IKKß binding domain in the absence of bound IKKß, thereby facilitating the structural characterization of small-molecule inhibitors.