Abstract Selected developments in the chemistry of heteroaromatic N-oxides since 2001 are presented in this review. The use of these Noxides, both in late-transition-metal-catalyzed oxidations of carbon– carbon triple bonds and in regioselective C–H functionalizations of the heteroarene, are contemporary topics of interest and the focus of the discussion.

The immune system must balance the need to maintain a diverse repertoire of lymphocytes to be able to fight infection with the need to maintain tolerance to self-proteins. The immune system places strict regulation over the ability of T cells to produce the major T cell growth factor interleukin 2 as this cytokine can influence a variety of immune outcomes. T cells require the delivery of two s...

Background. SOCS proteins are known to negatively regulate insulin signaling by inhibiting insulin receptor substrate-1 (IRS1). IRS1 has been reported to be a substrate for ubiquitin-dependent proteasomal degradation. Given that SOCS proteins can function as substrate receptor subunits of Cullin-5 E3 ubiquitin ligases, we examined whether Cullin-5 dependent ubiquitination is involved in the reg...

HECT domain E3 ubiquitin ligases of the NEDD4 family control many cellular processes, but their regulation is poorly understood. They contain multiple WW domains that recognize PY elements. Here, we show that the small PY-containing membrane proteins, NDFIP1 and NDFIP2 (NEDD4 family-interacting proteins), activate the catalytic activity of ITCH and of several other HECT ligases by binding to th...

Sequence analysis of the SalI g region of the genome of a virulent isolate of ASFV (Malawi Lil 20/1) has revealed an open reading frame with the potential to encode a 48 kilodalton (kD) polypeptide which has significant homology with eukaryotic and prokaryotic DNA ligases. This ASFV encoded gene also contains the putative active site region of DNA ligases including the lysine residue which is n...

Protein quality control (PQC) degradation protects the cell by preventing the toxic accumulation of misfolded proteins. In eukaryotes, PQC degradation is primarily achieved by ubiquitin ligases that attach ubiquitin to misfolded proteins for proteasome degradation. To function effectively, PQC ubiquitin ligases must distinguish misfolded proteins from their normal counterparts by recognizing an...

The COP9 signalosome (CSN) was initially discovered during the genetic analysis of light control of Arabidopsis seedling development and later shown to be a protein complex that is conserved among diverged organisms [1]. The accumulation of ubiquitin conjugated proteins and the failure to degrade specific proteins, such as HY5 and IAA6, in csn mutants [2–4] supports a role for CSN in the ubiqui...

DNA ligases are important enzymes required for cellular processes such as DNA replication, recombination, and repair. NAD(+)-dependent DNA ligases are essentially restricted to eubacteria, thus constituting an attractive target in the development of novel antibiotics. Although such a project might involve the systematic testing of a vast number of chemical compounds, it can essentially gain fro...