Nutritional Immunology: A Multi-Dimensional Approach

Nutrition is critical to immune defence and resistance to pathogens, with consequences that affect the health, welfare, and reproductive success of individual organisms [1], [2], and also has profound ecological and evolutionary implications [3]–[5]. In humans, under-nutrition, notably of protein, is a major contributor to morbidity and mortality due to infectious diseases, particularly in the developing world [1]. Likewise, over-nutrition and its associated metabolic disorders may impair immune function, disrupt the relationship with symbiotic and commensal microbiota, and increase susceptibility to infectious disease [6]. Despite the undoubted importance of nutrition to immune defence, the challenge remains to capture the complexity of this relationship. There are three main aspects to this complexity: (i) nutrition is a complex multi-dimensional problem for hosts, pathogens, and commensals; (ii) host immunity is a complex, multi-dimensional trait; and (iii) nutrition and immunity interact via multiple direct and indirect pathways, including involvement of the host's microbiota

Regulation of histone methylation by demethylimination and demethylation.

Histone methylation has important roles in regulating transcription, genome integrity and epigenetic inheritance. Historically, methylated histone arginine and lysine residues have been considered static modifications because of the low levels of methyl-group turnover in chromatin. The recent identification of enzymes that antagonize or remove histone methylation has changed this view and now the dynamic nature of these modifications is being appreciated. Here, we examine the enzymatic and structural basis for the mechanisms that these enzymes use to counteract histone methylation and provide insights into their substrate specificity and biological function

JmjC-domain-containing proteins and histone demethylation.

Histone methylation has important roles in regulating gene expression and forms part of the epigenetic memory system that regulates cell fate and identity. Enzymes that directly remove methyl marks from histones have recently been identified, revealing a new level of plasticity within this epigenetic modification system. Here we analyse the evolutionary relationship between Jumonji C (JmjC)-domain-containing proteins and discuss their cellular functions in relation to their potential enzymatic activities