TY - JOUR A1 - Scheffler, Christiane ED - Hermanussen, Michael T1 - Biological age JF - Auxology : Studying Human Growth and Development Y1 - 2013 SN - 978-3-510-65278-5 SP - 44 EP - 47 PB - Schweizerbart Science Publishers CY - Stuttgart ER - TY - JOUR A1 - Bröker, Nina Kristin A1 - Gohlke, Ulrich A1 - Müller, Jürgen J. A1 - Uetrecht, Charlotte A1 - Heinemann, Udo A1 - Seckler, Robert A1 - Barbirz, Stefanie T1 - Single amino acid exchange in bacteriophage HK620 tailspike protein results in thousand-fold increase of its oligosaccharide affinity JF - Glycobiology N2 - Bacteriophage HK620 recognizes and cleaves the O-antigen polysaccharide of Escherichia coli serogroup O18A1 with its tailspike protein (TSP). HK620TSP binds hexasaccharide fragments with low affinity, but single amino acid exchanges generated a set of high-affinity mutants with submicromolar dissociation constants. Isothermal titration calorimetry showed that only small amounts of heat were released upon complex formation via a large number of direct and solvent-mediated hydrogen bonds between carbohydrate and protein. At room temperature, association was both enthalpy- and entropy-driven emphasizing major solvent rearrangements upon complex formation. Crystal structure analysis showed identical protein and sugar conformers in the TSP complexes regardless of their hexasaccharide affinity. Only in one case, a TSP mutant bound a different hexasaccharide conformer. The extended sugar binding site could be dissected in two regions: first, a hydrophobic pocket at the reducing end with minor affinity contributions. Access to this site could be blocked by a single aspartate to asparagine exchange without major loss in hexasaccharide affinity. Second, a region where the specific exchange of glutamate for glutamine created a site for an additional water molecule. Side-chain rearrangements upon sugar binding led to desolvation and additional hydrogen bonding which define this region of the binding site as the high-affinity scaffold. KW - bacterial O-antigen KW - carbohydrate interaction KW - site-directed mutagenesis KW - structural thermodynamics KW - tailspike protein Y1 - 2013 U6 - https://doi.org/10.1093/glycob/cws126 SN - 0959-6658 VL - 23 IS - 1 SP - 59 EP - 68 PB - Oxford Univ. Press CY - Cary ER - TY - JOUR A1 - Taylan, Mehmet Sait A1 - Di Russo, Claudio A1 - Rampini, Mauro A1 - Ketmaier, Valerio T1 - Molecular systematics of the genus Troglophilus (Rhaphidophoridae, Orthoptera) in Turkey mitochondrial 16S rDNA evidences JF - ZooKeys N2 - This study focuses on the evolutionary relationships among Turkish species of the cave cricket genus Troglophilus. Fifteen populations were studied for sequence variation in a fragment (543 base pairs) of the mitochondrial DNA (mtDNA) 16S rDNA gene (16S) to reconstruct their phylogenetic relationships and biogeographic history. Genetic data retrieved three main clades and at least three divergent lineages that could not be attributed to any of the taxa known for the area. Molecular time estimates suggest that the diversification of the group took place between the Messinian and the Plio-Pleistocene. KW - Troglophilus KW - Rhaphidophoridae KW - Orthoptera KW - 16S rDNA KW - mitochondrial DNA KW - molecular systematics KW - cave crickets Y1 - 2013 U6 - https://doi.org/10.3897/zookeys.257.4133 SN - 1313-2989 IS - 257 SP - 33 EP - 46 PB - Pensoft Publ. CY - Sofia ER - TY - JOUR A1 - Pedersen, Henrik AE. A1 - Watthana, Santi A1 - Kocyan, Alexander A1 - Srimuang, Kanok-orn T1 - Pollination biology of Luisia curtisii (Orchidaceae) indications of a deceptive system operated by beetles JF - Plant systematics and evolution N2 - A population of Luisia curtisii (Orchidaceae: Aeridinae) in northern Thailand was studied with regard to pollination biology. Although a high level of self-compatibility was demonstrated experimentally, the very low natural fruit set (1.4-1.9 %) clearly indicated that the species depends on external agents for pollination. Our observations suggest that L. curtisii is pollinated by beetles, as Lema unicolor (Chrysomelidae) and Clinteria ducalis (Scarabaeidae) were the only flower visitors observed to carry pollinaria of this species. The hypothesis of specialised cantharophily is further supported by 2-methylbutyric acid and caproic acid being striking components of the floral scent. Judging from the lack of nectar and the behaviour of visiting beetles, the pollination system seems to rely on food or brood site deception. Retention of the anther on the pollinarium for some time after pollinarium removal probably reduces the frequency of insect-mediated autogamy and geitonogamy in Luisia curtisii-a possibility that was supported by comparative data on (1) the anther retention time and inflorescence visitation time of Lema unicolor and (2) stigma and anther length in the orchid. Existing reports of specialised beetle pollination in orchids are reviewed, and we conclude that there is accumulating evidence that specialised cantharophily is more common in the Orchidaceae than previously assumed. KW - Allogamy KW - Anther retention KW - Cantharophily KW - Floral scent KW - Fruit set KW - Outcrossing Y1 - 2013 U6 - https://doi.org/10.1007/s00606-012-0713-6 SN - 0378-2697 VL - 299 IS - 1 SP - 177 EP - 185 PB - Springer CY - Wien ER - TY - JOUR A1 - Fiorentino, V. A1 - Manganelli, Giuseppe A1 - Giusti, Folco A1 - Tiedemann, Ralph A1 - Ketmaier, Valerino T1 - A question of time the land snail Murella muralis (Gastropoda: Pulmonata) reveals constraints on past ecological speciation JF - Molecular ecology N2 - The lively debate about speciation currently focuses on the relative importance of factors driving population differentiation. While many studies are increasingly producing results on the importance of selection, little is known about the interaction between drift and selection. Moreover, there is still little knowledge on the spatial-temporal scales at which speciation occurs, that is, arrangement of habitat patches, abruptness of habitat transitions, climate and habitat changes interacting with selective forces. To investigate these questions, we quantified variation on a fine geographical scale analysing morphological (shell) and genetic data sets coupled with environmental data in the land snail Murella muralis, endemic to the Mediterranean island of Sicily. Analysis of a fragment of the mitochondrial DNA cytochrome oxidase I gene (COI) and eight nuclear microsatellite loci showed that genetic variation is highly structured at a very fine spatial scale by local palaeogeographical events and historical population dynamics. Molecular clock estimates, calibrated here specifically for Tyrrhenian land snails, provided a framework of palaeogeographical events responsible for the observed geographical variations and migration routes. Finally, we showed for the first time well-documented lines of evidence of selection in the past, which explains divergence of land snail shell shapes. We suggest that time and palaeogeographical history acted as constraints in the progress along the ecological speciation continuum. Our study shows that testing for correlation among palaeogeography, morphology and genetic data on a fine geographical scale provides information fundamental for a detailed understanding of ecological speciation processes. KW - allopatry KW - cytochrome oxidase I gene KW - ecological speciation KW - land snails KW - microsatellites KW - Murella Y1 - 2013 U6 - https://doi.org/10.1111/mec.12107 SN - 0962-1083 SN - 1365-294X VL - 22 IS - 1 SP - 170 EP - 186 PB - Wiley-Blackwell CY - Hoboken ER - TY - JOUR A1 - Hechavarria, Julio C. A1 - Macias, Silvio A1 - Vater, Marianne A1 - Mora, Emanuel C. A1 - Kössl, Manfred T1 - Evolution of neuronal mechanisms for echolocation specializations for target-range computation in bats of the genus Pteronotus JF - The journal of the Acoustical Society of America N2 - Delay tuning was studied in the auditory cortex of Pteronotus quadridens. All the 136 delay-tuned units that were studied responded strongly to heteroharmonic pulse-echo pairs presented at specific delays. In the heteroharmonic pairs, the first sonar call harmonic marks the timing of pulse emission while one of the higher harmonics (second or third) indicates the timing of the echo. Delay-tuned units are organized chronotopically along a rostrocaudal axis according to their characteristic delay. There is no obvious indication of multiple cortical axes specialized in the processing of different harmonic combinations of pulse and echo. Results of this study serve for a straight comparison of cortical delay-tuning between P. quadridens and the well-studied mustached bat, Pteronotus parnellii. These two species stem from the most recent and most basal nodes in the Pteronotus lineage, respectively. P. quadridens and P. parnellii use comparable heteroharmonic target-range computation strategies even though they do not use biosonar calls of a similar design. P. quadridens uses short constant-frequency (CF)/frequency-modulated (FM) echolocation calls, while P. parnellii uses long CF/FM calls. The ability to perform "heteroharmonic" target-range computations might be an ancestral neuronal specialization of the genus Pteronotus that was subjected to positive Darwinian selection in the evolution. Y1 - 2013 U6 - https://doi.org/10.1121/1.4768794 SN - 0001-4966 VL - 133 IS - 1 SP - 570 EP - 578 PB - American Institute of Physics CY - Melville 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 - Hartwich, Melanie A1 - Martin-Creuzburg, Dominik A1 - Wacker, Alexander T1 - Seasonal changes in the accumulation of polyunsaturated fatty acids in zooplankton JF - Journal of plankton research N2 - In aquatic food webs, consumers, such as daphnids and copepods, differ regarding their accumulation of polyunsaturated fatty acids (PUFAs). We tested if the accumulation of PUFAs in a seston size fraction containing different consumers and in Daphnia as a separate consumer is subject to seasonal changes in a large deep lake due to changes in the dietary PUFA supply and specific demands of different consumers. We found that the accumulation of arachidonic acid (ARA) in Daphnia increased from early summer to late summer and autumn. However, ARA requirements of Daphnia appeared to be constant throughout the year, because the accumulation of ARA increased when the dietary ARA supply decreased. In the size fraction 140 m, we found an increased accumulation of docosahexaenoic acid (DHA) during late summer and autumn. These seasonal changes in DHA accumulation were linked to changes in the proportion of copepods in this size fraction, which may have increasingly accumulated DHA for active overwintering. We show that consumer-specific PUFA demands can result in seasonal changes in PUFA accumulation, which may influence the trophic transfer of PUFAs within the food web. KW - accumulation KW - Daphnia KW - copepods KW - ARA KW - DHA Y1 - 2013 U6 - https://doi.org/10.1093/plankt/fbs078 SN - 0142-7873 VL - 35 IS - 1 SP - 121 EP - 134 PB - Oxford Univ. Press CY - Oxford ER - TY - JOUR A1 - Wissel, Jörg A1 - Manack, Aubrey A1 - Brainin, Michael T1 - Toward an epidemiology of poststroke spasticity JF - Neurology : official journal of the American Academy of Neurology N2 - Poststroke spasticity (PSS)-related disability is emerging as a significant health issue for stroke survivors. There is a need for predictors and early identification of PSS in order to minimize complications and maladaptation from spasticity. Reviewing the literature on stroke and upper motor neuron syndrome, spasticity, contracture, and increased muscle tone measured with the Modified Ashworth Scale and the Tone Assessment Scale provided data on the dynamic time course of PSS. Prevalence estimates of PSS were highly variable, ranging from 4% to 42.6%, with the prevalence of disabling spasticity ranging from 2% to 13%. Data on phases of the PSS continuum revealed evidence of PSS in 4% to 27% of those in the early time course (1-4 weeks poststroke), 19% to 26.7% of those in the postacute phase (1-3 months poststroke), and 17% to 42.6% of those in the chronic phase (>3 months poststroke). Data also identified key risk factors associated with the development of spasticity, including lower Barthel Index scores, severe degree of paresis, stroke-related pain, and sensory deficits. Although such indices could be regarded as predictors of PSS and thus enable early identification and treatment, the different measures of PSS used in those studies limit the strength of the findings. To optimize evaluation in the different phases of care, the best possible assessment of PSS would make use of a combination of indicators for clinical impairment, motor performance, activity level, quality of life, and patient-reported outcome measures. Applying these recommended measures, as well as increasing our knowledge of the physiologic predictors of PSS, will enable us to perform clinical and epidemiologic studies that will facilitate identification and early, multimodal treatment. Y1 - 2013 SN - 0028-3878 VL - 80 IS - 1 SP - S13 EP - S19 PB - Lippincott Williams & Wilkins CY - Philadelphia ER - TY - JOUR A1 - Sachse, Rita A1 - Wüstenhagen, Doreen Anja A1 - Samalikova, Maria A1 - Gerrits, Michael A1 - Bier, Frank Fabian A1 - Kubick, Stefan T1 - Synthesis of membrane proteins in eukaryotic cell-free systems JF - Engineering in life sciences : Industry, Environment, Plant, Food N2 - Cell-free protein synthesis (CFPS) is a valuable method for the fast expression of difficult-to-express proteins as well as posttranslationally modified proteins. Since cell-free systems circumvent possible cytotoxic effects caused by protein overexpression in living cells, they significantly enlarge the scale and variety of proteins that can be characterized. We demonstrate the high potential of eukaryotic CFPS to express various types of membrane proteins covering a broad range of structurally and functionally diverse proteins. Our eukaryotic cell-free translation systems are capable to provide high molecular weight membrane proteins, fluorescent-labeled membrane proteins, as well as posttranslationally modified proteins for further downstream analysis. KW - Cell-free protein expression KW - In vitro protein synthesis KW - Labeled membrane proteins KW - Synthetic glycoprotein Y1 - 2013 U6 - https://doi.org/10.1002/elsc.201100235 SN - 1618-0240 VL - 13 IS - 1 SP - 39 EP - 48 PB - Wiley-Blackwell CY - Hoboken ER -