How to prime your offspring:Putting behavioural ecology to the test

Natural selection favours traits that enhance the reproductive success of individuals. From an evolutionary perspective, reproductive success does not only depend on the number of offspring produced, but also on their condition, sex, and behaviour. In this thesis, I study the choices parents make to produce ‘the best’ offspring they can. To this end, I use various bird study systems and computer simulations. The first part of my thesis studies reproductive behaviour in the context of cooperative breeding, a breeding system where individuals help their parents to raise young instead of reproducing themselves. Under which circumstances should individuals forgo one's own reproduction in favour of the enhanced reproduction of others? Does cooperative breeding enhance the survival prospects of populations that live under harsh conditions? Does cooperative breeding affect the types (e.g. sons and daughters) of offspring produced? Next, this thesis discusses general questions regarding reproduction and natural selection. How should the ‘reproductive value’ of individuals be estimated in empirical systems? How can we infer the genetic basis of behaviour from empirical data? In a third part, I discuss potential mechanisms by which parents could affect the state of their offspring. I discuss how to disentangle early-life effects of the egg from parental effects after hatching in the nest, and investigate if birds can manipulate their offspring sex ratio based on glucose (a cue for body condition). I conclude that the assumptions underlying the study of the evolution of behaviour should be considered critically, as this could change conclusions dramatically

How to prime your offspring:Putting behavioural ecology to the test

Natural selection favours traits that enhance the reproductive success of individuals. From an evolutionary perspective, reproductive success does not only depend on the number of offspring produced, but also on their condition, sex, and behaviour. In this thesis, I study the choices parents make to produce ‘the best’ offspring they can. To this end, I use various bird study systems and computer simulations. The first part of my thesis studies reproductive behaviour in the context of cooperative breeding, a breeding system where individuals help their parents to raise young instead of reproducing themselves. Under which circumstances should individuals forgo one's own reproduction in favour of the enhanced reproduction of others? Does cooperative breeding enhance the survival prospects of populations that live under harsh conditions? Does cooperative breeding affect the types (e.g. sons and daughters) of offspring produced? Next, this thesis discusses general questions regarding reproduction and natural selection. How should the ‘reproductive value’ of individuals be estimated in empirical systems? How can we infer the genetic basis of behaviour from empirical data? In a third part, I discuss potential mechanisms by which parents could affect the state of their offspring. I discuss how to disentangle early-life effects of the egg from parental effects after hatching in the nest, and investigate if birds can manipulate their offspring sex ratio based on glucose (a cue for body condition). I conclude that the assumptions underlying the study of the evolution of behaviour should be considered critically, as this could change conclusions dramatically

How to prime your offspring:Putting behavioural ecology to the test

Natural selection favours traits that enhance the reproductive success of individuals. From an evolutionary perspective, reproductive success does not only depend on the number of offspring produced, but also on their condition, sex, and behaviour. In this thesis, I study the choices parents make to produce ‘the best’ offspring they can. To this end, I use various bird study systems and computer simulations. The first part of my thesis studies reproductive behaviour in the context of cooperative breeding, a breeding system where individuals help their parents to raise young instead of reproducing themselves. Under which circumstances should individuals forgo one's own reproduction in favour of the enhanced reproduction of others? Does cooperative breeding enhance the survival prospects of populations that live under harsh conditions? Does cooperative breeding affect the types (e.g. sons and daughters) of offspring produced? Next, this thesis discusses general questions regarding reproduction and natural selection. How should the ‘reproductive value’ of individuals be estimated in empirical systems? How can we infer the genetic basis of behaviour from empirical data? In a third part, I discuss potential mechanisms by which parents could affect the state of their offspring. I discuss how to disentangle early-life effects of the egg from parental effects after hatching in the nest, and investigate if birds can manipulate their offspring sex ratio based on glucose (a cue for body condition). I conclude that the assumptions underlying the study of the evolution of behaviour should be considered critically, as this could change conclusions dramatically

How to prime your offspring:Putting behavioural ecology to the test

Natural selection favours traits that enhance the reproductive success of individuals. From an evolutionary perspective, reproductive success does not only depend on the number of offspring produced, but also on their condition, sex, and behaviour. In this thesis, I study the choices parents make to produce ‘the best’ offspring they can. To this end, I use various bird study systems and computer simulations. The first part of my thesis studies reproductive behaviour in the context of cooperative breeding, a breeding system where individuals help their parents to raise young instead of reproducing themselves. Under which circumstances should individuals forgo one's own reproduction in favour of the enhanced reproduction of others? Does cooperative breeding enhance the survival prospects of populations that live under harsh conditions? Does cooperative breeding affect the types (e.g. sons and daughters) of offspring produced? Next, this thesis discusses general questions regarding reproduction and natural selection. How should the ‘reproductive value’ of individuals be estimated in empirical systems? How can we infer the genetic basis of behaviour from empirical data? In a third part, I discuss potential mechanisms by which parents could affect the state of their offspring. I discuss how to disentangle early-life effects of the egg from parental effects after hatching in the nest, and investigate if birds can manipulate their offspring sex ratio based on glucose (a cue for body condition). I conclude that the assumptions underlying the study of the evolution of behaviour should be considered critically, as this could change conclusions dramatically

How to prime your offspring:Putting behavioural ecology to the test

Natural selection favours traits that enhance the reproductive success of individuals. From an evolutionary perspective, reproductive success does not only depend on the number of offspring produced, but also on their condition, sex, and behaviour. In this thesis, I study the choices parents make to produce ‘the best’ offspring they can. To this end, I use various bird study systems and computer simulations. The first part of my thesis studies reproductive behaviour in the context of cooperative breeding, a breeding system where individuals help their parents to raise young instead of reproducing themselves. Under which circumstances should individuals forgo one's own reproduction in favour of the enhanced reproduction of others? Does cooperative breeding enhance the survival prospects of populations that live under harsh conditions? Does cooperative breeding affect the types (e.g. sons and daughters) of offspring produced? Next, this thesis discusses general questions regarding reproduction and natural selection. How should the ‘reproductive value’ of individuals be estimated in empirical systems? How can we infer the genetic basis of behaviour from empirical data? In a third part, I discuss potential mechanisms by which parents could affect the state of their offspring. I discuss how to disentangle early-life effects of the egg from parental effects after hatching in the nest, and investigate if birds can manipulate their offspring sex ratio based on glucose (a cue for body condition). I conclude that the assumptions underlying the study of the evolution of behaviour should be considered critically, as this could change conclusions dramatically

How to prime your offspring:Putting behavioural ecology to the test

Natural selection favours traits that enhance the reproductive success of individuals. From an evolutionary perspective, reproductive success does not only depend on the number of offspring produced, but also on their condition, sex, and behaviour. In this thesis, I study the choices parents make to produce ‘the best’ offspring they can. To this end, I use various bird study systems and computer simulations. The first part of my thesis studies reproductive behaviour in the context of cooperative breeding, a breeding system where individuals help their parents to raise young instead of reproducing themselves. Under which circumstances should individuals forgo one's own reproduction in favour of the enhanced reproduction of others? Does cooperative breeding enhance the survival prospects of populations that live under harsh conditions? Does cooperative breeding affect the types (e.g. sons and daughters) of offspring produced? Next, this thesis discusses general questions regarding reproduction and natural selection. How should the ‘reproductive value’ of individuals be estimated in empirical systems? How can we infer the genetic basis of behaviour from empirical data? In a third part, I discuss potential mechanisms by which parents could affect the state of their offspring. I discuss how to disentangle early-life effects of the egg from parental effects after hatching in the nest, and investigate if birds can manipulate their offspring sex ratio based on glucose (a cue for body condition). I conclude that the assumptions underlying the study of the evolution of behaviour should be considered critically, as this could change conclusions dramatically

Structural dissection of a complex Bacteroides ovatus gene locus conferring xyloglucan metabolism in the human gut

The human gastrointestinal tract harbours myriad bacterial species, collectively termed the microbiota, that strongly influence human health. Symbiotic members of our microbiota play a pivotal role in the digestion of complex carbohydrates that are otherwise recalcitrant to assimilation. Indeed, the intrinsic human polysaccharide-degrading enzyme repertoire is limited to various starch-based substrates; more complex polysaccharides demand microbial degradation. Select Bacteroidetes are responsible for the degradation of the ubiquitous vegetable xyloglucans (XyGs), through the concerted action of cohorts of enzymes and glycan-binding proteins encoded by specific xyloglucan utilization loci (XyGULs). Extending recent (meta) genomic, transcriptomic and biochemical analyses, significant questions remain regarding the structural biology of the molecular machinery required for XyG saccharification. Here, we reveal the three-dimensional structures of an α-xylosidase, a β-glucosidase, and two α-L-arabinofuranosidases from the Bacteroides ovatus XyGUL. Aided by bespoke ligand synthesis, our analyses highlight key adaptations in these enzymes that confer individual specificity for xyloglucan side chains and dictate concerted, stepwise disassembly of xyloglucan oligosaccharides. In harness with our recent structural characterization of the vanguard endo-xyloglucanse and cell-surface glycan-binding proteins, the present analysis provides a near-complete structural view of xyloglucan recognition and catalysis by XyGUL proteins

EZH2 Codon 641 Mutations are Common in BCL2-Rearranged Germinal Center B Cell Lymphomas

Mutations at codon 641 of EZH2 are recurrent in germinal center B cell lymphomas, and the most common variants lead to altered EZH2 enzymatic activity and enhanced tri-methylation of histone H3 at lysine 27, a repressive chromatin modification. As an initial step toward screening patients for cancer genotype-directed therapy, we developed a screening assay for EZH2 codon 641 mutations amenable for testing formalin-fixed clinical specimens, based on the sensitive SNaPshot single nucleotide extension technology. We detected EZH2 mutations in 12/55 (22%) follicular lymphomas (FL), 5/35 (14%) diffuse large B cell lymphomas with a germinal center immunophenotype (GCB-DLBCL), and 2/11 (18%) high grade B cell lymphomas with concurrent rearrangements of BCL2 and MYC. No EZH2 mutations were detected in cases of Burkitt lymphoma (0/23). EZH2 mutations were frequently associated with the presence of BCL2 rearrangement (BCL2-R) in both the FL (28% of BCL-R cases versus 0% of BCL2-WT cases, p<0.05) and GCB-DLBCL groups (33% of BCL2-R cases versus 4% of BCL2-WT cases, p<0.04), and across all lymphoma types excluding BL (27% of BCL2-R cases versus 3% of BCL2-WT cases, p<0.003). We confirmed gain-of-function activity for all previously reported EZH2 codon 641 mutation variants. Our findings suggest that EZH2 mutations constitute an additional genetic “hit” in many BCL2-rearranged germinal center B cell lymphomas. Our work may be helpful in the selection of lymphoma patients for future trials of pharmacologic agents targeting EZH2 and EZH2-regulated pathways

Impaired translation of CCAAT/enhancer binding protein alpha mRNA in bronchial smooth muscle cells of asthmatic patients

Bronchial smooth muscle (BSM) cells of asthmatic patients have an impaired expression of CCAAT/enhancer binding protein (C/EBP) alpha, which is associated with increased proliferation