Moving in the Anthropocene
(2018)
Animal movement is fundamental for ecosystem functioning and species survival, yet the effects of the anthropogenic footprint on animal movements have not been estimated across species. Using a unique GPS-tracking database of 803 individuals across 57 species, we found that movements of mammals in areas with a comparatively high human footprint were on average one-half to one-third the extent of their movements in areas with a low human footprint. We attribute this reduction to behavioral changes of individual animals and to the exclusion of species with long-range movements from areas with higher human impact. Global loss of vagility alters a key ecological trait of animals that affects not only population persistence but also ecosystem processes such as predator-prey interactions, nutrient cycling, and disease transmission.
Irish standard English
(2006)
Ironsulfur clusters (ISCs) are important prosthetic groups that define the functions of many proteins. Proteins with ISCs (called ironsulfur or FeS proteins) are present in mitochondria, the cytosol, the endoplasmic reticulum and the nucleus. They participate in various biological pathways including oxidative phosphorylation (OXPHOS), the citric acid cycle, iron homeostasis, heme biosynthesis and DNA repair. Here, we report a homozygous mutation in LYRM4 in two patients with combined OXPHOS deficiency. LYRM4 encodes the ISD11 protein, which forms a complex with, and stabilizes, the sulfur donor NFS1. The homozygous mutation (c.203GT, p.R68L) was identified via massively parallel sequencing of 1000 mitochondrial genes (MitoExome sequencing) in a patient with deficiency of complexes I, II and III in muscle and liver. These three complexes contain ISCs. Sanger sequencing identified the same mutation in his similarly affected cousin, who had a more severe phenotype and died while a neonate. Complex IV was also deficient in her skeletal muscle. Several other FeS proteins were also affected in both patients, including the aconitases and ferrochelatase. Mutant ISD11 only partially complemented for an ISD11 deletion in yeast. Our in vitro studies showed that the l-cysteine desulfurase activity of NFS1 was barely present when co-expressed with mutant ISD11. Our findings are consistent with a defect in the early step of ISC assembly affecting a broad variety of FeS proteins. The differences in biochemical and clinical features between the two patients may relate to limited availability of cysteine in the newborn period and suggest a potential approach to therapy.