iTRAQ-based quantitative proteomics discovering potential serum biomarkers in locoweed poisoned rabbits
CHEMICO-BIOLOGICAL INTERACTIONS
Authors: Jiao, Jifeng; Wang, Shuai; Zhang, Ruishi; Ma, Zhiyan; Du, Guofeng; Chen, Xiaolu; Tao, Dayong; Zhao, Jinxiang
Abstract
Locoism threatens the sustainable development of animal husbandry in areas around the world with intensified desertification, especially in the western United States, western China, Canada, and Mexico, among other countries. This study was conducted to discover potential serum biomarkers in locoweed-poisoned rabbits and lay a foundation for early diagnosis of locoism. We performed iTRAQ labeling coupled with two-dimensional liquid chromatography-tandem mass spectrometry (2D LC-MS/MS), comparing locoweed-poisoned rabbits and healthy controls. A total of 78 differentially-expressed proteins (fold change > 1.5 or < 0.67) were identified in the locoweed-poisoned rabbits compared to healthy controls. We found that 57.70% of differentially-expressed proteins were functionally related, and through bioinformatics analysis, we were able to construct a network mainly in complement and coagulation cascades. Significant differences in thrombospondin 4 (THBS4), kininogen 1 (KNG1), hemoglobin (HBB), and complement factor I (CFI) between locoweed poisoned animals and controls were found (P < 0.05) and validated by western blotting. These results suggested that locoweed could damage neurocytes, lower immunity, and form thrombi in rabbits. Our study proposes potential biomarkers for locoism diagnosis and also provides a new experimental basis to understand the pathogenesis of locoism. (C) 2017 Published by Elsevier Ireland Ltd.
Population-specific coding variant underlies genome-wide association with adiponectin level
HUMAN MOLECULAR GENETICS
Authors: Croteau-Chonka, Damien C.; Wu, Ying; Li, Yun; Fogarty, Marie P.; Lange, Leslie A.; Kuzawa, Christopher W.; McDade, Thomas W.; Borja, Judith B.; Luo, Jingchun; AbdelBaky, Omar; Combs, Terry P.; Adair, Linda S.; Lange, Ethan M.; Mohlke, Karen L.
Abstract
Adiponectin is a protein hormone that can affect major metabolic processes including glucose regulation and fat metabolism. Our previous genome-wide association (GWA) study of circulating plasma adiponectin levels in Filipino women from the Cebu Longitudinal Health and Nutrition Survey (CLHNS) detected a 100 kb twoSNP haplotype at KNG1-ADIPOQ associated with reduced adiponectin (frequency = 0.050, P = 1.8 x 10(-25)). Subsequent genotyping of CLHNS young adult offspring detected an uncommon variant [minor allele frequency (MAF) = 0.025] located similar to 800 kb from ADIPOQ that showed strong association with lower adiponectin levels (P = 2.7 x 10(-15), n = 1695) and tagged a subset of KNG1-ADIPOQ haplotype carriers with even lower adiponectin levels. Sequencing of the ADIPOQ-coding region detected variant R221S (MAF = 0.015, P = 2.9 x 10(-69)), which explained 17.1% of the variance in adiponectin levels and largely accounted for the initial GWA signal in Filipinos. R221S was not present in 12 514 Europeans with previously sequenced exons. To explore the mechanism of this substitution, we re-measured adiponectin level in 20 R221S offspring carriers and 20 non-carriers using two alternative antibodies and determined that the presence of R221S resulted in artificially low quantification of adiponectin level using the original immunoassay. These data provide an example of an uncommon variant responsible for a GWA signal and demonstrate that genetic associations with phenotypes measured by antibody-based quantification methods can be affected by uncommon coding SNPs residing in the antibody target region.