Ubiquitin Lys 63 chains – second-most abundant, but poorly understood in plants

Ubiquitin Lys 63 chains – second-most abundant, but poorly understood in plants

Covalent attachment of the small modifier ubiquitin to Lys ε-amino groups of proteins is surprisingly diverse. Once attached to a substrate, ubiquitin is itself frequently modified by ubiquitin, to form chains. All seven Lys residues of ubiquitin, as well as its N-terminal Met, can be ubiquitylated, implying cellular occurrence of different ubiquitin chain types. The available data suggest that...

Activated inositol 1,4,5-trisphosphate receptors are modified by homogeneous Lys-48- and Lys-63-linked ubiquitin chains, but only Lys-48-linked chains are required for degradation.

Inositol 1,4,5-trisphosphate (IP(3)) receptors (IP(3)Rs) are large, ubiquitously expressed, endoplasmic reticulum membrane proteins that form tetrameric IP(3) and Ca(2+)-gated Ca(2+) channels. Endogenous IP(3)Rs provide very appealing tools for studying the ubiquitin-proteasome pathway in intact mammalian cells because, upon activation, they are rapidly ubiquitinated and degraded. Using mass sp...

Thrombosis – Besieged but Poorly Understood

In biology, thrombosis is a mechanism of maintaining the integrity of biological surfaces in higher mammals, limiting fluid loss, and facilitating the recognition, containment, and destruction of pathogens and foreign materials by a scaffold of fibrin and DNA strands. However, thrombosis may also lead to vascular occlusion and subsequent tissue damage. In medicine, thrombosis is a hallmark of l...

Q Fever: An Old but Still a Poorly Understood Disease

Q fever is a bacterial infection affecting mainly the lungs, liver, and heart. It is found around the world and is caused by the bacteria Coxiella burnetii. The bacteria affects sheep, goats, cattle, dogs, cats, birds, rodents, and ticks. Infected animals shed this bacteria in birth products, feces, milk, and urine. Humans usually get Q fever by breathing in contaminated droplets released by in...

Premenstrual asthma: still poorly understood.