Biology subjects

Krauss, M.

Publications and source records attributed to Krauss, M..

4 recordsLinked to original sources

bioRxiv2024

Dataset of emerging contaminants in surface water, bottom water, porewater, and sediment: Urban and aquaculture impacts in the central and southern coast of Chile

Synthetic organic chemicals, including pesticides, pharmaceuticals, and industrial compounds, pose a growing threat to marine ecosystems as they enter through a variety of pathways, including direct discharges of wastewater (untreated or treated) from industrial, agricultural, and urban sources. Additionally, runoff from residential and agricultural land, as well as inland waterways, transport these chemicals to coastal zones. Despite their potential impact, data on the co-occurrence of these contaminants in the marine environment remains limited. Such information is critical for assessing coastal chemical status, establishing environmental quality benchmarks, and conducting comprehensive environmental risk assessments. In this study, we describe a multifaceted monitoring campaign targeting pesticides, pharmaceuticals, and industrial chemicals along the central-south coast and in northern Patagonia, Chile. Surface water, bottom water, porewater, and adjacent sediment samples were collected for analysis. Our results show the detection of up to 83 chemicals in surface water, 71 in bottom water, 101 in porewater, and 244 in sediments. To enhance data utility, we provide valuable information on the mode of action and molecular targets of the identified chemicals. This comprehensive dataset contributes to defining pollution fingerprints in coastal areas of the Global South, including remote regions in Patagonia. It serves as a critical resource for future research, policymaking, and the advancement of environmental protection in these regions.

pharmacology and toxicology↗

bioRxiv2024

Septin-associated PIPKIγ splice variants drive centralspindlin association with the midbody via PI(4,5)P2

Mammalian cytokinesis critically depends on the phospholipid phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2] which serves as docking site for crucial components of the cytokinetic machinery at the plasma membrane. PI(4,5)P2 supports several stages of cytokinesis, including actomyosin ring assembly and constriction, membrane tethering of spindle microtubules, and midbody organization. How these various activities of PI(4,5)P2 and the underlying mechanisms of local PI(4,5)P2 synthesis are orchestrated in space and time has remained elusive. Here, we identify a pivotal role of septin-binding splice variants of PIPKI{gamma} that couple nanoscale PI(4,5)P2 synthesis at the ingressing cleavage furrow to late midbody formation. Depletion of PIPKI{gamma} isoforms causes multinucleation and perturbs anillin and septin deposition at the intercellular bridge and at the midbody. These defects are rescued by wild-type kinase, but not by septin binding-deficient or catalytically inactive PIPKI{gamma} variants. We further show that both, septins and PIPKI{gamma} form a complex with centralspindlin, and thereby facilitate the recruitment of centralspindlin to the midbody. Taken together, our findings establish septin-associated PIPKI{gamma} isoforms as key regulators of midbody organization that act through generating a local pool of PI4,5P2 required for centralspindlin recruitment and maintenance at the midbody, and for septin association with microtubules.

cell biology↗

bioRxiv2023

A multi-scenario risk assessment strategy applied to mixtures of chemicals of emerging concern in the River Aconcagua basin in Central Chile

Streams and rivers are characterised by the presence of various chemicals of emerging concern (CECs), including pesticides, pharmaceuticals, personal care products, and industrial chemicals. While these chemicals are found usually only in low (ng/L) concentrations, they might still harm aquatic life and disrupt the ecological balance of aquatic ecosystems due to their high ecotoxicological potency. Environmental risk assessments that account for the complexity of exposures are needed in order to evaluate the toxic pressure of these chemicals, which also provide suggestions for risk mitigation and management, if necessary. Currently, most studies on the co-occurrence and environmental impacts of CECs are conducted in countries of the Global North, leaving massive knowledge gaps in countries of the Global South. In this study, we implement a multi-scenario risk assessment strategy to improve the assessment of both the exposure and hazard components in the chemical risk assessment process. Our strategy incorporates a systematic consideration and weighting of CECs that were not detected, as well as an evaluation of the uncertainties associated with Quantitative Structure-Activity Relationships (QSARs) predictions for chronic ecotoxicity. Furthermore, we present a novel approach to identifying mixture risk drivers. To expand our knowledge beyond well-studied aquatic ecosystems, we applied this multi-scenario strategy to the River Aconcagua basin of Central Chile. The analysis revealed that the concentrations of CECs exceeded acceptable risk thresholds for selected organism groups and the most vulnerable taxonomic groups. Streams flowing through agricultural areas and sites near the river mouth exhibited the highest risks. Notably, the eight risk drivers among the 153 co-occurring chemicals accounted for 66-92% of the observed risks in the river basin. Six of them are pesticides and pharmaceuticals, chemical classes known for their high biological activity in specific target organisms. Graphical abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=80 SRC="FIGDIR/small/554257v1_ufig1.gif" ALT="Figure 1"> View larger version (21K): org.highwire.dtl.DTLVardef@179dc1dorg.highwire.dtl.DTLVardef@162082aorg.highwire.dtl.DTLVardef@10616baorg.highwire.dtl.DTLVardef@be1b32_HPS_FORMAT_FIGEXP M_FIG C_FIG HighlightsO_LI153 chemicals of emerging concern detected in complex multi-component mixtures. C_LIO_LI108 possible mixture risk assessment scenarios were investigated. C_LIO_LINon-detects, QSARs, and experimental ecotoxicological data were integrated for risk assessment. C_LIO_LI8 chemicals of emerging concern were responsible for driving chronic environmental risks. C_LI

pharmacology and toxicology↗

bioRxiv2022

Amino acid availability acts as a metabolic rheostat to determine the magnitude of ILC2 responses

Group 2 innate lymphoid cells (ILC2) are functionally poised, tissue-resident lymphocytes that respond rapidly to damage and infection at mucosal barrier sites. ILC2 reside within complex microenvironments where they are subject to cues from the diet, commensal microbiota and invading pathogens - most notably helminths. Emerging evidence suggests ILC2 are acutely sensitive not only to canonical activating signals, but also perturbations in nutrient and metabolite availability. In the context of helminth infection, we identify amino acid availability as a nutritional cue in regulating ILC2 responses. ILC2 were found to be uniquely pre-primed to import amino acids via the large neutral amino acid transporters Slc7a5 and Slc7a8. Cell-intrinsic deletion of these transporters impaired ILC2 expansion, but not cytokine production, in part via tuning of mTOR activation. These findings implicate the import of amino acids as a metabolic requisite for optimal ILC2 responses, and further highlight nutritional cues as critical regulators of innate immune responses within mucosal barrier tissues.

immunology↗