Evaluating Habitat-based Niche Requirements and Potential Recruitment Bottlenecks for Imperiled Bluehead Sucker (Catostomus discobolus)

Changes to rivers that alter physical and thermal habitat may cause fish population abundance to decline, due to fewer individuals maturing and entering the adult population. The Weber River has become highly degraded with many dams and diversions altering fish habitat, river volume, velocity, and temperature, and limiting movement between reaches. Bluehead suckers (Catostomus discobolus) occupy only 47% of their historical range and the genetically-distinct Weber River (northern UT) population is declining and contains few young, juvenile fish. My objectives were to determine whether spawning and rearing habitat available in the Weber River may be limiting bluehead sucker reproductive success and population growth. I used reach-based surveys to locate and quantify spawning habitat in the Weber River and Ferron Creek (central Utah), a relatively unaltered river for comparison. I sampled slow-water backwaters near (\u3c 1 km) spawning reaches for juvenile sucker and surveyed habitat characteristics. I conducted laboratory experiments to evaluate the effect different temperature and velocity treatments (12-19°C, 0.004-0.18 m/s) have on juvenile bluehead sucker growth. In the Weber River and Ferron Creek, reaches with gravel (4-64 mm diameter), cobble (64-256 mm diameter), and pools (6-26 pools/km) were used by spawning bluehead sucker. In Weber River backwaters, deeper backwaters contained significantly more juvenile sucker (18-378 sucker; range: 19-87 cm max depth). Laboratory results indicated that juvenile bluehead sucker growth was greatest in the cooler temperature and slower velocity treatments. Collectively these results suggest spawning habitat is limited by the availability of small, rocky substrate and pools and rearing habitat is limited by the availability of deep, slow backwaters at the optimal temperature. By evaluating factors that may limit bluehead sucker population growth, this study will provide a template for future restoration efforts directed at recovering this imperiled population

Gene × environment interaction by a longitudinal epigenome-wide association study (LEWAS) overcomes limitations of genome-wide association study (GWAS)

The goal of genome-wide association studies is to identify SNPs unique to disease. It usually involves a single sampling from subjects' lifetimes. While primary DNA sequence variation influences gene-expression levels, expression is also influenced by epigenetics, including the ‘somatic epitype’ (GSE), an epigenotype acquired postnatally. While genes are inherited, and novel polymorphisms do not routinely appear, GSE is fluid. Furthermore, GSE could respond to environmental factors (such as heavy metals) and to differences in exercise, maternal care and dietary supplements – all of which postnatally modify oxidation or methylation of DNA, leading to altered gene expression. Change in epigenetic status may be critical for the development of many diseases. We propose a ‘longitudinal epigenome-wide association study’, wherein GSE are measured at multiple time points along with subjects' histories. This Longitudinal epigenome-wide association study, based on the ‘dynamic’ somatic epitype over the ‘static’ genotype, merits further investigation

Latent consequences of early-life lead (Pb) exposure and the future: Addressing the Pb crisis

Background. The lead (Pb) exposure crisis in Flint, Michigan has passed from well-publicized event to a footnote, while its biological and social impact will linger for lifetimes. Interest in the “water crisis” has dropped to pre-event levels, which is neither appropriate nor safe. Flint’s exposure was severe, but it was not unique. Problematic Pb levels have also been found in schools and daycares in 42 states in the USA. The enormity of Pb exposure via municipal water systems requires multiple responses. Herein, we focus on addressing a possible answer to long-term sequelae of Pb exposure. We propose “4R’s” (remediation, renovation, reallocation, and research) against the Pb crisis that goes beyond a short-term fix. Remediation for affected individuals must continue to provide clean water and deal with both short and long-term effects of Pb exposure. Renovation of current water delivery systems, at both system-wide and individual site levels, is necessary. Reallocation of resources is needed to ensure these two responses occur and to get communities ready for potential sequelae of Pb exposure. Finally, properly focused research can track exposed individuals and illuminate latent (presumably epigenetic) results of Pb exposure and inform further resource reallocation. Conclusion. Motivation to act by not only the general public but also by scientific and medical leaders must be maintained beyond initial news cycle spikes and an annual follow-up story. Environmental impact of Pb contamination of drinking water goes beyond one exposure incident in an impoverished and forgotten Michigan city. Population effects must be addressed long-term and nationwide

When figures and data contradict text: MiR346 is apparently reduced in breast cancer tissue, contrary to claims by a paper's author

A recent article in Gene highlighted potential function of miR-346 in human breast cancer (Yang et al., 2017). We request an explanation or correction of the report. In its current state, the text will certainly create confusion in the field and lead to incorrect assumptions. The authors made several critical errors. The abstract stated “we found that the expression of miR-346 was higher in breast cancer tissues than in their paired corresponding non-cancerous tissues” and the main text and legend for Fig. 1A stated “miR-346 expression was significantly higher in breast cancer tissues than in their paired corresponding non-cancerous tissues (Fig. 1A, Yang et al., 2017)” and “miR-346 was upregulated in breast cancer tissues and cell lines. (A)”, respectively. It was also stated that “SRCIN1 expression levels were significantly down-regulated in breast cancer compared to the adjacent normal tissues (Fig. 5B, Yang et al., 2017)”. The problem with these statements is that they contradict the actual data presented in the paper! This misrepresentation of the effects of miR-346 in breast cancer could prove harmful by sidetracking future research. Further, clinical trials may be incorrectly directed towards lowering miR-346 without a complete and fair assessment of the internal contradictions in the data. Inaccurately-presented data impede progress of biomedical research, deplete scientific resources and compromise public trust

The LEARn model: an epigenetic explanation for idiopathic neurobiological disease

Neurobiological disorders have diverse manifestations and symptomology. Neurodegenerative disorders such as Alzheimer’s disease (AD) manifest late in life and are characterized by, among other symptoms, progressive loss of synaptic markers. Developmental disorders, such as autism spectrum, appear in childhood. Neuropsychiatric and affective disorders, such as schizophrenia and major depressive disorder, respectively, have broad ranges of age of onset and symptoms. However, all share uncertain etiologies, with opaque relationships between genes and environment. We propose a “Latent Early–life Associated Regulation” (LEARn) model, positing latent changes in expression of specific genes initially primed at the developmental stage of life. In this model, environmental agents epigenetically disturb gene regulation in a long–term fashion, beginning at early developmental stages, but these perturbations might not have pathological results until significantly later in life. The LEARn model operates through the regulatory region (promoter) of the gene, specifically through changes in methylation and oxidation status within the promoter of specific genes. The LEARn model combines genetic and environmental risk factors in an epigenetic pathway to explain the etiology of the most common, i.e., sporadic, forms of neurobiological disorders

Charter School Funding: Inequity’s Next Frontier

Of all the controversies swirling around the nation’s charter schools, none is more hotly contested than the debate over funding. Charter opponents charge that] these autonomous public schools are draining scarce resources from public school districts. Proponents, by contrast, complain that charter schools do not get their fair share of public education dollars

Lithium alters expression of RNAs in a type-specific manner in differentiated human neuroblastoma neuronal cultures, including specific genes involved in Alzheimer's disease.

Lithium (Li) is a medication long-used to treat bipolar disorder. It is currently under investigation for multiple nervous system disorders, including Alzheimer's disease (AD). While perturbation of RNA levels by Li has been previously reported, its effects on the whole transcriptome has been given little attention. We, therefore, sought to determine comprehensive effects of Li treatment on RNA levels. We cultured and differentiated human neuroblastoma (SK-N-SH) cells to neuronal cells with all-trans retinoic acid (ATRA). We exposed cultures for one week to lithium chloride or distilled water, extracted total RNA, depleted ribosomal RNA and performed whole-transcriptome RT-sequencing. We analyzed results by RNA length and type. We further analyzed expression and protein interaction networks between selected Li-altered protein-coding RNAs and common AD-associated gene products. Lithium changed expression of RNAs in both non-specific (inverse to sequence length) and specific (according to RNA type) fashions. The non-coding small nucleolar RNAs (snoRNAs) were subject to the greatest length-adjusted Li influence. When RNA length effects were taken into account, microRNAs as a group were significantly less likely to have had levels altered by Li treatment. Notably, several Li-influenced protein-coding RNAs were co-expressed or produced proteins that interacted with several common AD-associated genes and proteins. Lithium's modification of RNA levels depends on both RNA length and type. Li activity on snoRNA levels may pertain to bipolar disorders while Li modification of protein coding RNAs may be relevant to AD

Lessons from a BACE1 inhibitor trial: off-site but not off base

Alzheimer's disease (AD) is characterized by formation of neuritic plaque primarily composed of a small filamentous protein called amyloid-β peptide (Aβ). The rate-limiting step in the production of Aβ is the processing of Aβ precursor protein (APP) by β-site APP-cleaving enzyme (BACE1). Hence, BACE1 activity plausibly plays a rate-limiting role in the generation of potentially toxic Aβ within brain and the development of AD, thereby making it an interesting drug target. A phase II trial of the promising LY2886721 inhibitor of BACE1 was suspended in June 2013 by Eli Lilly and Co., due to possible liver toxicity. This outcome was apparently a surprise to the study's team, particularly since BACE1 knockout mice and mice treated with the drug did not show such liver toxicity. Lilly proposed that the problem was not due to LY2886721 anti-BACE1 activity. We offer an alternative hypothesis, whereby anti-BACE1 activity may induce apparent hepatotoxicity through inhibiting BACE1's processing of β-galactoside α-2,6-sialyltransferase I (STGal6 I). In knockout mice, paralogues, such as BACE2 or cathepsin D, could partially compensate. Furthermore, the short duration of animal studies and short lifespan of study animals could mask effects that would require several decades to accumulate in humans. Inhibition of hepatic BACE1 activity in middle-aged humans would produce effects not detectable in mice. We present a testable model to explain the off-target effects of LY2886721 and highlight more broadly that so-called off-target drug effects might actually represent off-site effects that are not necessarily off-target. Consideration of this concept in forthcoming drug design, screening, and testing programs may prevent such failures in the future

PuF, An Antimetastatic and Developmental Signaling Protein, Interacts with the Alzheimer’s Amyloid-β Precursor Protein via a Tissue-Specific Proximal Regulatory Element (PRE)

Background: Alzheimer’s disease (AD) is intimately tied to amyloid-β (Aβ) peptide. Extraneuronal brain plaques consisting primarily of Aβ aggregates are a hallmark of AD. Intraneuronal Aβ subunits are strongly implicated in disease progression. Protein sequence mutations of the Aβ precursor protein (APP) account for a small proportion of AD cases, suggesting that regulation of the associated gene (APP) may play a more important role in AD etiology. The APP promoter possesses a novel 30 nucleotide sequence, or “proximal regulatory element” (PRE), at −76/−47, from the +1 transcription start site that confers cell type specificity. This PRE contains sequences that make it vulnerable to epigenetic modification and may present a viable target for drug studies. We examined PRE-nuclear protein interaction by gel electrophoretic mobility shift assay (EMSA) and PRE mutant EMSA. This was followed by functional studies of PRE mutant/reporter gene fusion clones. Results: EMSA probed with the PRE showed DNA-protein interaction in multiple nuclear extracts and in human brain tissue nuclear extract in a tissue-type specific manner. We identified transcription factors that are likely to bind the PRE, using competition gel shift and gel supershift: Activator protein 2 (AP2), nm23 nucleoside diphosphate kinase/metastatic inhibitory protein (PuF), and specificity protein 1 (SP1). These sites crossed a known single nucleotide polymorphism (SNP). EMSA with PRE mutants and promoter/reporter clone transfection analysis further implicated PuF in cells and extracts. Functional assays of mutant/reporter clone transfections were evaluated by ELISA of reporter protein levels. EMSA and ELISA results correlated by meta-analysis. Conclusions: We propose that PuF may regulate the APP gene promoter and that AD risk may be increased by interference with PuF regulation at the PRE. PuF is targeted by calcium/calmodulin-dependent protein kinase II inhibitor 1, which also interacts with the integrins. These proteins are connected to vital cellular and neurological functions. In addition, the transcription factor PuF is a known inhibitor of metastasis and regulates cell growth during development. Given that APP is a known cell adhesion protein and ferroxidase, this suggests biochemical links among cell signaling, the cell cycle, iron metabolism in cancer, and AD in the context of overall aging