Tagging of Weakly Expressed Toxoplasma gondii Calcium-Related Genes with High-Affinity Tags.

Calcium ions regulate a diversity of cellular functions in all eukaryotes. The cytosolic Ca2+ concentration is tightly regulated at the physiological cytosolic concentration of 50-100 nm. The Toxoplasma gondii genome predicts the presence of several genes encoding potential Ca2+ channels, pumps, and transporters. Many of these genes are weakly expressed and likely tightly regulated due to their potential impact to the physiology of the cell. Endogenous tagging has been widely used to localize proteins in T. gondii but low level of expression of many of them makes visualization of tags difficult and sometimes impossible. The use of high-performance tags for labeling proteins expressed at low level is ideal for investigating the localization of these gene products. We designed a Carboxy-terminus tagging plasmid containing the previously characterized "spaghetti monster-HA" (smHA) or "spaghetti monster-MYC" (smMYC) tags. These tags consist of 10 copies of a single epitope (HA or MYC) inserted into a darkened green fluorescence protein scaffold. We localized six proteins of various levels of expression. Clonal lines were isolated and validated by PCR, western blot, and immunofluorescence analyses. Some gene products were only visible when tagged with smHA and in one case the smHA revealed a novel localization previously undetected.

The socioeconomic factors surrounding the initial emergence of peste des petits ruminants in Kenya, Uganda, and Tanzania from 2006 through 2008.

Peste des petits ruminants (PPR) is a devastating disease of small ruminants that significantly hinders productivity in endemic areas. Kenya, Uganda and Tanzania reported their first cases in each country between 2006 and 2008 despite the disease being present in the region (Ethiopia and Sudan) since the 1990s. The time leading up to the outbreaks involved refugee movements, drought, civil unrest, and resulted in increased animal mingling, movement and density in these regions. Refugee camps with animal source food demands and a robust informal economy further added to the development of animal mingling and movement as well. Once introduced, common pastoral migration lands and trade routes likely transported the disease throughout the region. This paper highlights why trade routes, refugee camps and areas of animal crowding during droughts should be targeted for interventions, monitoring and surveillance as part of PPR control in a region.