The endoplasmic reticulum-associated mRNA-binding proteins ERBP1 and ERBP2 interact in bloodstream-form Trypanosoma brucei

Kinetoplastids rely heavily on post-transcriptional mechanisms for control of gene expression, and on RNA-binding proteins that regulate mRNA splicing, translation and decay. Trypanosoma brucei ERBP1 (Tb927.10.14150) and ERBP2 (Tb927.9.9550) were previously identified as mRNA binding proteins that lack canonical RNA-binding domains. We show here that ERBP1 is associated with the endoplasmic reticulum, like ERBP2, and that the two proteins interact in vivo. Loss of ERBP1 from bloodstreamform T. brucei initially resulted in a growth defect but proliferation was restored after more prolonged cultivation. Pull-down analysis of tagged ERBP1 suggests that it preferentially binds to ribosomal protein mRNAs. The ERBP1 sequence resembles that of Saccharomyces cerevisiae Bfr1, which also localises to the endoplasmic reticulum and binds to ribosomal protein mRNAs. However, unlike Bfr1, ERBP1 does not bind to mRNAs encoding secreted proteins, and it is also not recruited to stress granules after starvation.Fil: Bajak, Kathrin. Universität Heidelberg; AlemaniaFil: Leiss, Kevin. Universität Heidelberg; AlemaniaFil: Clayton, Christine E.. Universität Heidelberg; AlemaniaFil: Erben, Esteban Daniel. Universidad Nacional de San Martín. Instituto de Investigaciones Biotecnológicas. - Consejo Nacional de Investigaciones Científicas y Técnicas. Oficina de Coordinación Administrativa Parque Centenario. Instituto de Investigaciones Biotecnológicas; Argentin

Genomic analysis suggests higher susceptibility of children to air pollution

Differences in biological responses to exposure to hazardous airborne substances between children and adults have been reported, suggesting children to be more susceptible. Aim of this study was to improve our understanding of differences in susceptibility in cancer risk associated with air pollution by comparing genome-wide gene expression profiles in peripheral blood of children and their parents. Gene expression analysis was performed in blood from children and parents living in two different regions in the Czech Republic with different levels of air pollution. Data were analyzed by two different approaches: one method first selected significantly differentially expressed genes and analyzed these gene lists for overrepresented biological processes, whereas the other applied the T-profiler tool to directly perform pathway analyses on the total gene set without preselection of significantly modulated gene expressions. In addition, gene expressions in both children and adults were investigated for associations with micronuclei frequencies. Both analysis approaches returned considerably more genes or gene groups and pathways that significantly differed between children from both regions than between parents. Very little overlap was observed between children and adults. The two most important biological processes or molecular functions significantly modulated in children, but not in adults, are nucleosome and immune response related. Our study suggests differences between children and adults in relation to air pollution exposure at the transcriptome level. The findings underline the necessity of implementing environmental health policy measures specifically for protecting children's health. © The Author 2008. Published by Oxford University Press. All rights reserved