TY - JOUR A1 - Hohmann, S. A1 - Buchmann, Arlette F. A1 - Witt, S. H. A1 - Rietschel, M. A1 - Jennen-Steinmetz, Christine A1 - Schmidt, M. H. A1 - Esser, Günter A1 - Banaschewski, Tobias A1 - Laucht, Manfred T1 - Increasing association between a neuropeptide Y promoter polymorphism and body mass index during the course of development JF - Pediatric obesity N2 - Objective: To investigate the association of the neuropeptide Y (NPY) promoter polymorphism rs16147 with body mass index (BMI) during the course of development from infancy to adulthood. Design: Longitudinal, prospective study of a German community sample. Subjects: n = 306 young adults (139 males, 167 females). Measurements: Participants' body weight and height were assessed at the ages of 3 months and 2, 4.5, 8, 11, 15 and 19 years. NPY rs16147 was genotyped. Results: Controlling for a number of possible confounders, homozygote carriers of the rs16147 C allele exhibited significantly lower BMI scores when compared with individuals carrying the T allele. In addition, a significant genotype by age interaction emerged, indicating that the genotype effect increased during the course of development. Conclusions: This is the first longitudinal study to report an association between rs16147 and BMI during childhood and adolescence. The finding that this effect increased during the course of development may either be due to age-dependent alterations in gene expression or to maturation processes within the weight regulation circuits of the central nervous system. KW - Development KW - neuropeptide Y KW - rs16147 KW - weight regulation Y1 - 2012 U6 - https://doi.org/10.1111/j.2047-6310.2012.00069.x SN - 2047-6310 VL - 7 IS - 6 SP - 453 EP - 460 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Junemann, Alexander A1 - Winterhoff, Moritz A1 - Nordholz, Benjamin A1 - Rottner, Klemens A1 - Eichinger, Ludwig A1 - Gräf, Ralph A1 - Faix, Jan T1 - ForC lacks canonical formin activity but bundles actin filaments and is required for multicellular development of Dictyostelium cells JF - European journal of cell biology N2 - Diaphanous-related formins (DRFs) drive the nucleation and elongation of linear actin filaments downstream of Rho GTPase signalling pathways. Dictyostelium formin C (ForC) resembles a DRF, except that it lacks a genuine formin homology domain 1 (FH1), raising the questions whether or not ForC can nucleate and elongate actin filaments. We found that a recombinant ForC-FH2 fragment does not nucleate actin polymerization, but moderately decreases the rate of spontaneous actin assembly and disassembly, although the barbed-end elongation rate in the presence of the formin was not markedly changed. However, the protein bound to and crosslinked actin filaments into loose bundles of mixed polarity. Furthermore, ForC is an important regulator of morphogenesis since ForC-null cells are severely impaired in development resulting in the formation of aberrant fruiting bodies. Immunoblotting revealed that ForC is absent during growth, but becomes detectable at the onset of early aggregation when cells chemotactically stream together to form a multicellular organism, and peaks around the culmination stage. Fluorescence microscopy of cells ectopically expressing a GFP-tagged, N-terminal ForC fragment showed its prominent accumulation in the leading edge, suggesting that ForC may play a role in cell migration. In agreement with its expression profile, no defects were observed in random migration of vegetative mutant cells. Notably, chemotaxis of starved cells towards a source of cAMP was severely impaired as opposed to control. This was, however, largely due to a marked developmental delay of the mutant, as evidenced by the expression profile of the early developmental marker csA. In line with this, chemotaxis was almost restored to wild type levels after prolonged starvation. Finally, we observed a complete failure of phototaxis due to abolished slug formation and a massive reduction of spores consistent with forC promoter-driven expression of beta-galactosidase in prespore cells. Together, these findings demonstrate ForC to be critically involved in signalling of the cytoskeleton during various stages of development. KW - Actin bundles KW - Cell migration KW - Chemotaxis KW - Development KW - Dictyostelium KW - Formin KW - Morphogenesis KW - Phototaxis KW - Spore formation Y1 - 2013 U6 - https://doi.org/10.1016/j.ejcb.2013.07.001 SN - 0171-9335 VL - 92 IS - 6-7 SP - 201 EP - 212 PB - Elsevier CY - Jena ER - TY - JOUR A1 - Müller, Juliane A1 - Müller, Steffen A1 - Baur, Heiner A1 - Mayer, Frank T1 - Intra-individual gait speed variability in healthy children aged 1-15 years JF - Gait & posture N2 - Introduction: Gait speed is one of the most commonly and frequently used parameters to evaluate gait development. It is characterized by high variability when comparing different steps in children. The objective of this study was to determine intra-individual gait speed variability in children. Methods: Gait speed measurements (6-10 trials across a 3 m walkway) were performed and analyzed in 8263 children, aged 1-15 years. The coefficient of variation (CV) served as a measure for intra-individual gait speed variability measured in 6.6 +/- 1.0 trials per child. Multiple linear regression analysis was conducted to evaluate the influence of age and body height on changes in variability. Additionally, a subgroup analysis for height within the group of 6-year-old children was applied. Results: A successive reduction in gait speed variability (CV) was observed for age groups (age: 1-15 years) and body height groups (height: 0.70-1.90 m). The CV in the oldest subjects was only one third of the CV (CV 6.25 +/- 3.52%) in the youngest subjects (CV 16.58 +/- 10.01%). Up to the age of 8 years (or 1.40 m height) there was a significant reduction in CV over time, compared to a leveling off for the older (taller) children. Discussion: The straightforward approach measuring gait speed variability in repeated trials might serve as a fundamental indicator for gait development in children. Walking velocity seems to increase to age 8. Enhanced gait speed consistency of repeated trials develops up to age 15. KW - Development KW - Gait KW - Speed KW - Variability KW - Children Y1 - 2013 U6 - https://doi.org/10.1016/j.gaitpost.2013.02.011 SN - 0966-6362 SN - 1879-2219 VL - 38 IS - 4 SP - 631 EP - 636 PB - Elsevier CY - Clare ER - TY - JOUR A1 - Tsukaya, Hirokazu A1 - Byrne, Mary E. A1 - Horiguchi, Gorou A1 - Sugiyama, Munetaka A1 - Van Lijsebettens, Mieke A1 - Lenhard, Michael T1 - How do 'housekeeping' genes control organogenesis?-unexpected new findings on the role of housekeeping genes in cell and organ differentiation JF - Journal of plant research N2 - In recent years, an increasing number of mutations in what would appear to be 'housekeeping genes' have been identified as having unexpectedly specific defects in multicellular organogenesis. This is also the case for organogenesis in seed plants. Although it is not surprising that loss-of-function mutations in 'housekeeping' genes result in lethality or growth retardation, it is surprising when (1) the mutant phenotype results from the loss of function of a 'housekeeping' gene and (2) the mutant phenotype is specific. In this review, by defining housekeeping genes as those encoding proteins that work in basic metabolic and cellular functions, we discuss unexpected links between housekeeping genes and specific developmental processes. In a surprising number of cases housekeeping genes coding for enzymes or proteins with functions in basic cellular processes such as transcription, post-transcriptional modification, and translation affect plant development. KW - Development KW - Housekeeping genes KW - Post-transcriptional modification KW - RNAPII KW - Pre-mRNA splicing KW - Ribosome KW - 3 '-end processing KW - Transcription KW - Translation Y1 - 2013 U6 - https://doi.org/10.1007/s10265-012-0518-2 SN - 0918-9440 VL - 126 IS - 1 SP - 3 EP - 15 PB - Springer CY - Tokyo ER - TY - JOUR A1 - Mehnert, Jan A1 - Akhrif, Atae A1 - Telkemeyer, Silke A1 - Rossi, Sonja A1 - Schmitz, Christoph H. A1 - Steinbrink, Jens A1 - Wartenburger, Isabell A1 - Obrig, Hellmuth A1 - Neufang, Susanne T1 - Developmental changes in brain activation and functional connectivity during response inhibition in the early childhood brain JF - Brain and development : official journal of the Japanese Society of Child Neurology N2 - Response inhibition is an attention function which develops relatively early during childhood. Behavioral data suggest that by the age of 3, children master the basic task requirements for the assessment of response inhibition but performance improves substantially until the age of 7. The neuronal mechanisms underlying these developmental processes, however, are not well understood. In this study, we examined brain activation patterns and behavioral performance of children aged between 4 and 6 years compared to adults by applying a go/no-go paradigm during near-infrared spectroscopy (NIRS) brain imaging. We furthermore applied task-independent functional connectivity measures to the imaging data to identify maturation of intrinsic neural functional networks. We found a significant group x condition related interaction in terms of inhibition-related reduced right fronto-parietal activation in children compared to adults. In contrast, motor-related activation did not differ between age groups. Functional connectivity analysis revealed that in the children's group, short-range coherence within frontal areas was stronger, and long-range coherence between frontal and parietal areas was weaker, compared to adults. Our findings show that in children aged from 4 to 6 years fronto-parietal brain maturation plays a crucial part in the cognitive development of response inhibition. KW - Optical tomography KW - NIRS KW - Response inhibition KW - Functional connectivity KW - Development KW - Early childhood Y1 - 2013 U6 - https://doi.org/10.1016/j.braindev.2012.11.006 SN - 0387-7604 SN - 1872-7131 VL - 35 IS - 10 SP - 894 EP - 904 PB - Elsevier CY - Amsterdam ER - TY - JOUR A1 - Huynen, Leon A1 - Suzuki, Takayuki A1 - Ogura, Toshihiko A1 - Watanabe, Yusuke A1 - Millar, Craig D. A1 - Hofreiter, Michael A1 - Smith, Craig A1 - Mirmoeini, Sara A1 - Lambert, David M. T1 - Reconstruction and in vivo analysis of the extinct tbx5 gene from ancient wingless moa (Aves: Dinornithiformes) JF - BMC evolutionary biology N2 - Background: The forelimb-specific gene tbx5 is highly conserved and essential for the development of forelimbs in zebrafish, mice, and humans. Amongst birds, a single order, Dinornithiformes, comprising the extinct wingless moa of New Zealand, are unique in having no skeletal evidence of forelimb-like structures. Results: To determine the sequence of tbx5 in moa, we used a range of PCR-based techniques on ancient DNA to retrieve all nine tbx5 exons and splice sites from the giant moa, Dinornis. Moa Tbx5 is identical to chicken Tbx5 in being able to activate the downstream promotors of fgf10 and ANF. In addition we show that missexpression of moa tbx5 in the hindlimb of chicken embryos results in the formation of forelimb features, suggesting that Tbx5 was fully functional in wingless moa. An alternatively spliced exon 1 for tbx5 that is expressed specifically in the forelimb region was shown to be almost identical between moa and ostrich, suggesting that, as well as being fully functional, tbx5 is likely to have been expressed normally in moa since divergence from their flighted ancestors, approximately 60 mya. KW - tbx5 KW - Moa KW - Gene expression KW - Ancient DNA KW - Development KW - Forelimb Y1 - 2014 U6 - https://doi.org/10.1186/1471-2148-14-75 SN - 1471-2148 VL - 14 PB - BioMed Central CY - London ER - TY - JOUR A1 - Müller-Röber, Bernd A1 - Balazadeh, Salma T1 - Auxin and its role in plant senescence JF - Journal of plant growth regulation N2 - Leaf senescence represents a key developmental process through which resources trapped in the photosynthetic organ are degraded in an organized manner and transported away to sustain the growth of other organs including newly forming leaves, roots, seeds, and fruits. The optimal timing of the initiation and progression of senescence are thus prerequisites for controlled plant growth, biomass accumulation, and evolutionary success through seed dispersal. Recent research has uncovered a multitude of regulatory factors including transcription factors, micro-RNAs, protein kinases, and others that constitute the molecular networks that regulate senescence in plants. The timing of senescence is affected by environmental conditions and abiotic or biotic stresses typically trigger a faster senescence. Various phytohormones, including for example ethylene, abscisic acid, and salicylic acid, promote senescence, whereas cytokinins delay it. Recently, several reports have indicated an involvement of auxin in the control of senescence, however, its mode of action and point of interference with senescence control mechanisms remain vaguely defined at present and contrasting observations regarding the effect of auxin on senescence have so far hindered the establishment of a coherent model. Here, we summarize recent studies on auxin-related genes that affect senescence in plants and highlight how these findings might be integrated into current molecular-regulatory models of senescence. KW - ARF KW - Auxin KW - Chloroplast KW - Development KW - Leaf KW - SAUR KW - Senescence KW - Signaling KW - Transcription factor KW - YUCCA Y1 - 2014 U6 - https://doi.org/10.1007/s00344-013-9398-5 SN - 0721-7595 SN - 1435-8107 VL - 33 IS - 1 SP - 21 EP - 33 PB - Springer CY - New York ER - TY - JOUR A1 - Stapel, Janny C. A1 - Hunnius, Sabine A1 - Bekkering, Harold A1 - Lindemann, Oliver T1 - The development of numerosity estimation: Evidence for a linear number representation early in life JF - Journal of cognitive psychology N2 - Several studies investigating the development of approximate number representations used the number-to-position task and reported evidence for a shift from a logarithmic to a linear representation of numerical magnitude with increasing age. However, this interpretation as well as the number-to-position method itself has been questioned recently. The current study tested 5- and 8-year-old children on a newly established numerosity production task to examine developmental changes in number representations and to test the idea of a representational shift. Modelling of the children's numerical estimations revealed that responses of the 8-year-old children approximate a simple positive linear relation between estimated and actual numbers. Interestingly, however, the estimations of the 5-year-old children were best described by a bilinear model reflecting a relatively accurate linear representation of small numbers and no apparent magnitude knowledge for large numbers. Taken together, our findings provide no support for a shift of mental representations from a logarithmic to a linear metric but rather suggest that the range of number words which are appropriately conceptualised and represented by linear analogue magnitude codes expands during development. KW - Numerical estimation KW - Number cognition KW - Development KW - Bilinear models KW - Number representation Y1 - 2015 U6 - https://doi.org/10.1080/20445911.2014.995668 SN - 2044-5911 SN - 2044-592X VL - 27 IS - 4 SP - 400 EP - 412 PB - Routledge, Taylor & Francis Group CY - Abingdon ER - TY - JOUR A1 - von der Malsburg, Titus Raban A1 - Kliegl, Reinhold A1 - Vasishth, Shravan T1 - Determinants of Scanpath Regularity in Reading JF - Cognitive science : a multidisciplinary journal of anthropology, artificial intelligence, education, linguistics, neuroscience, philosophy, psychology ; journal of the Cognitive Science Society N2 - Scanpaths have played an important role in classic research on reading behavior. Nevertheless, they have largely been neglected in later research perhaps due to a lack of suitable analytical tools. Recently, von der Malsburg and Vasishth (2011) proposed a new measure for quantifying differences between scanpaths and demonstrated that this measure can recover effects that were missed with the traditional eyetracking measures. However, the sentences used in that study were difficult to process and scanpath effects accordingly strong. The purpose of the present study was to test the validity, sensitivity, and scope of applicability of the scanpath measure, using simple sentences that are typically read from left to right. We derived predictions for the regularity of scanpaths from the literature on oculomotor control, sentence processing, and cognitive aging and tested these predictions using the scanpath measure and a large database of eye movements. All predictions were confirmed: Sentences with short words and syntactically more difficult sentences elicited more irregular scanpaths. Also, older readers produced more irregular scanpaths than younger readers. In addition, we found an effect that was not reported earlier: Syntax had a smaller influence on the eye movements of older readers than on those of young readers. We discuss this interaction of syntactic parsing cost with age in terms of shifts in processing strategies and a decline of executive control as readers age. Overall, our results demonstrate the validity and sensitivity of the scanpath measure and thus establish it as a productive and versatile tool for reading research. KW - Eye movements KW - Reading KW - Scanpaths KW - Language understanding KW - Oculo-motor control KW - Individual differences KW - Aging KW - Development Y1 - 2015 U6 - https://doi.org/10.1111/cogs.12208 SN - 0364-0213 SN - 1551-6709 VL - 39 IS - 7 SP - 1675 EP - 1703 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Peres, Tanara V. A1 - Eyng, Helena A1 - Lopes, Samantha C. A1 - Colle, Dirleise A1 - Goncalves, Filipe M. A1 - Venske, Debora K. R. A1 - Lopes, Mark W. A1 - Ben, Juliana A1 - Bornhorst, Julia A1 - Schwerdtle, Tanja A1 - Aschner, Michael A. A1 - Farina, Marcelo A1 - Prediger, Rui D. A1 - Leal, Rodrigo B. T1 - Developmental exposure to manganese induces lasting motor and cognitive impairment in rats JF - Neurotoxicology : the interdisciplinary journal of effects to toxic substances on the nervous system N2 - Exposure to high manganese (Mn) levels may damage the basal ganglia, leading to a syndrome analogous to Parkinson's disease, with motor and cognitive impairments. The molecular mechanisms underlying Mn neurotoxicity, particularly during development, still deserve further investigation. Herein, we addressed whether early-life Mn exposure affects motor coordination and cognitive function in adulthood and potential underlying mechanisms. Male Wistar rats were exposed intraperitoneally to saline (control) or MnCl2 (5, 10 or 20 mg/kg/day) from post-natal day (PND) 8-12. Behavioral tests were performed on PND 60-65 and biochemical analysis in the striatum and hippocampus were performed on PND14 or PND70. Rats exposed to Mn (10 and 20 mg/kg) performed significantly worse on the rotarod test than controls indicating motor coordination and balance impairments. The object and social recognition tasks were used to evaluate short-term memory. Rats exposed to the highest Mn dose failed to recognize a familiar object when replaced by a novel object as well as to recognize a familiar juvenile rat after a short period of time. However, Mn did not alter olfactory discrimination ability. In addition, Mn-treated rats displayed decreased levels of non-protein thiols (e.g. glutathione) and increased levels of glial fibrillary acidic protein (GFAP) in the striatum. Moreover, Mn significantly increased hippocampal glutathione peroxidase (GPx) activity. These findings demonstrate that acute low-level exposure to Mn during a critical neurodevelopmental period causes cognitive and motor dysfunctions that last into adulthood, that are accompanied by alterations in antioxidant defense system in both the hippocampus and striatum. (C) 2015 Elsevier Inc. All rights reserved. KW - Manganese KW - Neurotoxicity KW - Development KW - Motor coordination KW - Cognition Y1 - 2015 U6 - https://doi.org/10.1016/j.neuro.2015.07.005 SN - 0161-813X SN - 1872-9711 VL - 50 SP - 28 EP - 37 PB - Elsevier CY - Amsterdam ER -