Preface to the Princeton Landmarks in Biology Edition vii Preface xi Symbols Used xiii 1. The Importance of Islands 3 2. Area and Number of Speicies 8 3. Further Explanations of the Area-Diversity Pattern 19 4. The Strategy of Colonization 68 5. Invasibility and the Variable Niche 94 6. Stepping Stones and Biotic Exchange 123 7. Evolutionary Changes Following Colonization 145 8. Prospect 181 Glossary 185 References 193 Index 201

The Theory of Island Biogeography

I have developed "tennis elbow" from lugging this book around the past four weeks, but it is worth the pain, the effort, and the aspirin. It is also worth the (relatively speaking) bargain price. Including appendixes, this book contains 894 pages of text. The entire panorama of the neural sciences is surveyed and examined, and it is comprehensive in its scope, from genomes to social behaviors. The editors explicitly state that the book is designed as "an introductory text for students of biology, behavior, and medicine," but it is hard to imagine any audience, interested in any fragment of neuroscience at any level of sophistication, that would not enjoy this book. The editors have done a masterful job of weaving together the biologic, the behavioral, and the clinical sciences into a single tapestry in which everyone from the molecular biologist to the practicing psychiatrist can find and appreciate his or

Principles of Neural Science

The secretion of glucocorticoids (GCs) is a classic endocrine response to stress. Despite that, it remains controversial as to what purpose GCs serve at such times. One view, stretching back to the time of Hans Selye, posits that GCs help mediate the ongoing or pending stress response, either via basal levels of GCs permitting other facets of the stress response to emerge efficaciously, and/or by stress levels of GCs actively stimulating the stress response. In contrast, a revisionist viewpoint posits that GCs suppress the stress response, preventing it from being pathologically overactivated. In this review, we consider recent findings regarding GC action and, based on them, generate criteria for determining whether a particular GC action permits, stimulates, or suppresses an ongoing stressresponse or, as an additional category, is preparative for a subsequent stressor. We apply these GC actions to the realms of cardiovascular function, fluid volume and hemorrhage, immunity and inflammation, metabolism, neurobiology, and reproductive physiology. We find that GC actions fall into markedly different categories, depending on the physiological endpoint in question, with evidence for mediating effects in some cases, and suppressive or preparative in others. We then attempt to assimilate these heterogeneous GC actions into a physiological whole. (Endocrine Reviews 21: 55‐ 89, 2000)

/pdf/how-do-glucocorticoids-influence-stress-responses-4egr3fa2k0.pdf

How do glucocorticoids influence stress responses? Integrating permissive, suppressive, stimulatory, and preparative actions.

Between the 1960s and 1980s, most life scientists focused their attention on studies of nucleic acids and the translation of the coded information. Protein degradation was a neglected area, conside...

The Ubiquitin-Proteasome Proteolytic Pathway: Destruction for the Sake of Construction

In response to stress, the brain activates several neuropeptide-secreting systems. This eventually leads to the release of adrenal corticosteroid hormones, which subsequently feed back on the brain and bind to two types of nuclear receptor that act as transcriptional regulators. By targeting many genes, corticosteroids function in a binary fashion, and serve as a master switch in the control of neuronal and network responses that underlie behavioural adaptation. In genetically predisposed individuals, an imbalance in this binary control mechanism can introduce a bias towards stress-related brain disease after adverse experiences. New candidate susceptibility genes that serve as markers for the prediction of vulnerable phenotypes are now being identified.

Stress and the brain: from adaptation to disease

Publisher Summary The yeast Saccharomyces cerevisiae (S. cerevisiae) is described as a model eukaryotic organism, due to the many fundamental similarities shared between itself and the cells, albeit differentiated, of higher eukaryotes, such as humans. This chapter describes yeast as a model for juvenile neuronal ceroid lypofuscinose (JNCL). The value of yeast as a tool for understanding the function of a protein relies heavily on the ease of which the specific genes from the yeast can be deleted and the effect of the absence of the gene can be assessed. The model suggests that Btn1p is a vacuolar protein, and the yeast lacking the protein have a defective vacuolar pH, or at least a defective regulation of vacuolar pH. “Batten disease yeast model” described in the chapter, is based on the fact that the whole genome of S. cerevisiae was sequenced revealing that this yeast had a protein homologous to CLN3. Recently, second yeast, Schizosaccharomyces pombe (S. pombe), has had its entire genome sequenced. This revealed that S. pombe also contains a homolog to human CLN3. In addition S. pombe contains a protein that is 32% identical and 47% similar to human CLN1, a protein thiolesterase that is associated to infantile NCL.

Experimental models of NCL: the yeast model.

Accumulated evidence indicates that the gut microbiota affects brain function and may be altered in neurological diseases. In this study, we analyzed the gut microbiota in Cln1R151X and Cln2R207X mice, models of the childhood neurodegenerative disorders, infantile CLN1 and late infantile CLN2 Batten diseases. Significant alterations were found in the overall gut microbiota composition and also at the individual taxonomic ranks as compared to wild-type mice. The disease-specific alterations in the gut microbiota of Cln1R151X and Cln2R207X mice may contribute to the disease phenotypes observed in these mouse models. We also compared the gut microbiota composition of three wild-type mouse strains frequently used in transgenic studies: 129S6/SvEv, C57BL/6J and mixed 129S6/SvEv × C57BL/6J. Our results show that the gut microbiota of 129S6/SvEv and C57BL/6J mice differs remarkably, which likely contributes to the known, pronounced differences in behavior and disease susceptibility between these two wild-type mouse strains.

Comparative analysis of the gut microbiota composition in the Cln1 R151X and Cln2 R207X mouse models of Batten disease and in three wild-type mouse strains.

Low-complexity delayless acoustic echo cancellation techniques based on frequency-domain spline-identification are proposed and investigated. Two methods of approximation of the acoustic frequency response, both using B-splines, are con- sidered: the optimal-spline method and the local-spline method. The optimal-spline method seeks the solution of a least squares problem. The most computationally demanding part of the method, solution of the normal equations, is implemented by using the low-complexity dichotomous coordinate descent algorithm. The local-spline method avoids solving the normal equations, enabling further simplification; this is at the expense of a slight degradation in the cancellation performance. A novel efficient double-talk detector is also proposed, being an inherent feature of the frequency-domain identification. Open-loop and closed-loop identification schemes with cubic splines are studied by simulation and compared with the fast affine projection (FAP) algorithm. The proposed techniques provide cancellation performance better than that of the FAP algorithm, especially in double-talk and noisy environments, with a lower complexity.

Acoustic Echo Cancellation Using Frequency-Domain

Significance Statement Rapid renal responses to ingested potassium are essential to prevent hyperkalemia and also play a central role in blood pressure regulation. Although local extracellular K + concentration in kidney tissue is increasingly recognized as an important regulator of K + secretion, the underlying mechanisms that are relevant in vivo remain controversial. To assess the role of the signaling kinase mTOR complex-2 (mTORC2), the authors compared the effects of K + administered by gavage in wild-type mice and knockout mice with kidney tubule-specific inactivation of mTORC2. They found that mTORC2 is rapidly activated to trigger K + secretion and maintain electrolyte homeostasis. Downstream targets of mTORC2 implicated in epithelial sodium channel regulation (SGK1 and Nedd4-2) were concomitantly phosphorylated in wild-type, but not knockout, mice. These findings offer insight into electrolyte physiologic and regulatory mechanisms. Background Increasing evidence implicates the signaling kinase mTOR complex-2 (mTORC2) in rapid renal responses to changes in plasma potassium concentration [K + ]. However, the underlying cellular and molecular mechanisms that are relevant in vivo for these responses remain controversial. Methods We used Cre-Lox–mediated knockout of rapamycin-insensitive companion of TOR (Rictor) to inactivate mTORC2 in kidney tubule cells of mice. In a series of time-course experiments in wild-type and knockout mice, we assessed urinary and blood parameters and renal expression and activity of signaling molecules and transport proteins after a K + load by gavage. Results A K + load rapidly stimulated epithelial sodium channel (ENaC) processing, plasma membrane localization, and activity in wild-type, but not in knockout, mice. Downstream targets of mTORC2 implicated in ENaC regulation (SGK1 and Nedd4-2) were concomitantly phosphorylated in wild-type, but not knockout, mice. We observed differences in urine electrolytes within 60 minutes, and plasma [K + ] was greater in knockout mice within 3 hours of gavage. Renal outer medullary potassium (ROMK) channels were not acutely stimulated in wild-type or knockout mice, nor were phosphorylation of other mTORC2 substrates (PKC and Akt). Conclusions The mTORC2-SGK1-Nedd4-2-ENaC signaling axis is a key mediator of rapid tubule cell responses to increased plasma [K + ] in vivo . The effects of K + on this signaling module are specific, in that other downstream mTORC2 targets, such as PKC and Akt, are not acutely affected, and ROMK and Large-conductance K + (BK) channels are not activated. These findings provide new insight into the signaling network and ion transport systems that underlie renal responses to K + in vivo . 

https://www.zora.uzh.ch/id/eprint/232766/1/Potassium_Activates_mTORC2_dependent_SGK1.97.pdf

David A. Pearce

Papers

Experimental models of NCL: the yeast model.

Comparative analysis of the gut microbiota composition in the Cln1 R151X and Cln2 R207X mouse models of Batten disease and in three wild-type mouse strains.

Acoustic Echo Cancellation Using Frequency-Domain

Potassium Activates mTORC2-dependent SGK1 Phosphorylation to Stimulate Epithelial Sodium Channel: Role in Rapid Renal Responses to Dietary Potassium

Testing combinatorial therapies for juvenile Batten disease: Lysosome (2018)