Endogenously-expressed NH2-terminus of circumsporozoite protein interferes with sporozoite invasion of mosquito salivary glands

Abstract\ud \ud Background\ud The circumsporozoite protein is the most abundant polypeptide expressed by sporozoites, the malaria parasite stage capable of infecting humans. Sporozoite invasion of mosquito salivary glands prior to transmission is likely mediated by a receptor/ligand-like interaction of the parasites with the target tissues, and the amino (NH2)-terminal portion of CSP is involved in this interaction but not the TSR region on the carboxyl (C)-terminus. Peptides based on the NH2-terminal domain could compete with the parasites for the salivary gland receptors and thus inhibit penetration.\ud \ud \ud Methods\ud Peptides based on the NH2-terminus and TSR domains of the CSP from avian or human malaria parasites, Plasmodium gallinaceum and Plasmodium falciparum, respectively, were expressed endogenously in mosquito haemolymph using a transient (Sindbis virus-mediated) or stable (piggyBac-mediated transgenesis) system.\ud \ud \ud Results\ud Transient endogenous expression of partial NH2-terminus peptide from P. falciparum CSP in P. gallinaceum-infected Aedes aegypti resulted in a reduced number of sporozoites in the salivary glands. When a transgenic approach was used to express a partial CSP NH2-terminal domain from P. gallinaceum the number of sporozoites in the salivary glands did not show a difference when compared to controls. However, a significant difference could be observed when mosquitoes with a lower infection were analysed. The same result could not be observed with mosquitoes endogenously expressing peptides based on the TSR domain from either P. gallinaceum or P. falciparum.\ud \ud \ud \ud Conclusion\ud These results support the conclusion that CSP partial NH2-terminal domain can be endogenously expressed to promote a competition for the receptor used by sporozoites to invade salivary glands, and they could be used to block this interaction and reduce parasite transmission. The same effect cannot be obtained with peptides based on the TSR domain.We thank Neuza Saraiva Fernandes and Ediane Saraiva Fernandes for technical\ud assistance and Alexandre Santos de Moura for sample sequencing. This work\ud was supported by FAPESP (Process#04/00889-9 and#00/12138-7). AAJ was\ud supported in part by an award from the National Institute of Allergy and Infec‑\ud tious Diseases (USA) (R37AI029746)

nanos-Driven expression of piggyBac transposase induces mobilization of a synthetic autonomous transposon in the malaria vector mosquito, Anopheles stephensi.

Transposons are a class of selfish DNA elements that can mobilize within a genome. If mobilization is accompanied by an increase in copy number (replicative transposition), the transposon may sweep through a population until it is fixed in all of its interbreeding members. This introgression has been proposed as the basis for drive systems to move genes with desirable phenotypes into target species. One such application would be to use them to move a gene conferring resistance to malaria parasites throughout a population of vector mosquitos. We assessed the feasibility of using the piggyBac transposon as a gene-drive mechanism to distribute anti-malarial transgenes in populations of the malaria vector, Anopheles stephensi. We designed synthetic gene constructs that express the piggyBac transposase in the female germline using the control DNA of the An. stephensi nanos orthologous gene linked to marker genes to monitor inheritance. Two remobilization events were observed with a frequency of one every 23 generations, a rate far below what would be useful to drive anti-pathogen transgenes into wild mosquito populations. We discuss the possibility of optimizing this system and the impetus to do so

Influence of criminal activity of sentenced women and of their imprisonment during an execution of punishment on perception of guilt and meaningfulness of life

The doctoral thesis is engaged in the question of guilt, compassion - repentance, forgiveness, responsibility and meaningfulness of existence in the sentenced women's lives at the beginning and during their execution of punishment. Guilt is presented from Christian, philosophical- psychological point of view and also from the perspective of law. Guilt is usually prosecuted by punishment. The next chapter analyzes what kind of punishment is adequate to what guilt, which punishment is positive and which one is negative. The next chapter is devoted to a term of compassion-or repentance- as an inevitable part of the forgiving process. An author perceives forgiveness towards self and others as a necessary part of "the healing process", towards which the work of specialists in execution of punishment should be directed. Forgiveness is unthinkable without acceptance of own responsibility for one's decisions and deeds. Perception of own meaningfulness is connected with all mentioned topics. The last chapter in the theoretical part of the paper is devoted to the subject of meaning of life and loss of its meaning. The practical part focuses on the group of women sentenced for a violent crime and on the group of women sentenced for property crime. Each group is further divided according to length of their imprisonment..

nanos-Driven expression of piggyBac transposase induces mobilization of a synthetic autonomous transposon in the malaria vector mosquito, Anopheles stephensi

Transposons are a class of selfish DNA elements that can mobilize within a genome. If mobilization is accompanied by an increase in copy number (replicative transposition), the transposon may sweep through a population until it is fixed in all of its interbreeding members. This introgression has been proposed as the basis for drive systems to move genes with desirable phenotypes into target species. One such application would be to use them to move a gene conferring resistance to malaria parasites throughout a population of vector mosquitos. We assessed the feasibility of using the piggyBac transposon as a gene-drive mechanism to distribute anti-malarial transgenes in populations of the malaria vector, Anopheles stephensi. We designed synthetic gene constructs that express the piggyBac transposase in the female germline using the control DNA of the An. stephensi nanos orthologous gene linked to marker genes to monitor inheritance. Two remobilization events were observed with a frequency of one every 23 generations, a rate far below what would be useful to drive anti-pathogen transgenes into wild mosquito populations. We discuss the possibility of optimizing this system and the impetus to do so