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Phenotypic Properties (phenotypic + property)
Selected AbstractsCOEVOLUTION OF COLOR PATTERN AND THERMOREGULATORY BEHAVIOR IN POLYMORPHIC PYGMY GRASSHOPPERS TETRIX UNDULATAEVOLUTION, Issue 2 2002Anders Forsman Abstract Ectothermic organisms, such as insects and reptiles, rely on external heat sources to control body temperature and possess physiological and behavioral traits that are temperature dependent. It has therefore been hypothesised that differences in body temperature resulting from phenotypic properties, such as color pattern, may translate into selection against thermally inferior phenotypes. We tested for costs and benefits of pale versus dark coloration by comparing the behaviors (i.e., basking duration and bouts) of pygmy grasshopper (Tetrix undulata) individuals exposed to experimental situations imposing a trade-off between temperature regulation and feeding. We used pairs consisting of two full-siblings of the same sex that represented different (genetically coded) color morphs but had shared identical conditions from the time of fertilization. Our results revealed significant differences in behavioral thermoregulation between dark and pale individuals in females, but not in males. Pale females spent more time feeding than dark females, regardless of whether feeding was associated with a risk of either hypothermia or overheating. In contrast, only minor differences in behavior (if any) were evident between individuals that belonged to the same color morph but had been painted black or gray to increase and decrease their heating rates. This suggests that the behavioral differences between individuals belonging to different color morphs are genetically determined, rather than simply reflecting a response to different heating rates. To test for effects of acclimation on behaviors, we used pairs of individuals that had been reared from hatchlings to adults under controlled conditions in either low or high temperature. The thermal regime experienced during rearing had little effect on behaviors during the experiments reported above, but significantly influenced the body temperatures selected in a laboratory thermal gradient. In females (but not in males) preferred body temperature also varied among individuals born to mothers belonging to different color morphs, suggesting that a genetic correlation exists between color pattern and temperature preferences. Collectively, these findings, at least in females, are consistent with the hypothesis of multiple-trait coevolution and suggest that the different color morphs represent alternative evolutionary strategies. [source] Characterization of adhesin variants in Indian isolates of enteroaggregative Escherichia coliFEMS MICROBIOLOGY LETTERS, Issue 2 2006Renu Bhardwaj Abstract Enteroaggregative Escherichia coli (EAEC) are causative agents of diarrhea, being characterized by aggregative adherence to cultured epithelial cells. In this study, phenotypic properties of EAEC were analyzed with respect to AA, hemagglutination, clump and biofilm formation, all of which are mediated by aggregative adherence fimbriae (AAF). The strains were also screened for AAF types, AAF adhesin variants and Dr adhesin by PCR. Of the three known AAF types, AAF/I and AAF/II adhesin variants were identified. An association between the AAF/adhesin genotypes and the subtypes/scores of phenotypic properties was sought and it was observed that strains harboring same adhesins displayed different subtypes/scores and vice versa. [source] Phenotypic characteristics of novel swine-origin influenza A/California/07/2009 (H1N1) virusINFLUENZA AND OTHER RESPIRATORY VIRUSES, Issue 1 2010Irina Kiseleva Background, The 2009 novel A(H1N1) virus appears to be of swine origin. This strain causing the current outbreaks is a new virus that has not been seen previously either in humans or animals. We have previously reported that viruses causing pandemics or large outbreaks were able to grow at a temperature above the normal physiological range (temperature resistance, non-ts phenotype), were found to be inhibitor resistant and restricted in replication at suboptimal temperature (sensitivity to grow at low temperature, non-ca phenotype). In this study, we performed phenotypic analysis of novel A(H1N1) virus to evaluate its pandemic potential and its suitability for use in developing a live attenuated influenza vaccine. Objectives, The goal of this study is to identify phenotypic properties of novel A(H1N1) influenza virus. Methods, A/California/07/2009 (H1N1) swine-origin influenza virus was studied in comparison with some influenza A viruses isolated in different years with respect to their ability to grow at non-permissive temperatures. We also analyzed its sensitivity to gamma-inhibitors of animal sera and its ability to agglutinate chicken, human and guinea pig erythrocytes. Results, Swine-origin A/California/07/2009 (H1N1) virus was found to be non-ts and inhibitor resistant and was not able to grow at 25°C (non-ca). We did not find any difference in the ability of the hemagglutinin of A/California/07/2009 (H1N1) virus to bind to erythrocytes of different origin. Conclusion, The novel swine-origin A(H1N1) virus displays a phenotype typical of the past pandemic and epidemic viruses. This finding suggests that this virus might be a good wild type parental prototype for live vaccine for potential use for controlling pandemic influenza. [source] Murine in vitro whole bladder model: A method for assessing phenotypic responses to pharmacologic stimuli and hypoxiaNEUROUROLOGY AND URODYNAMICS, Issue 4 2004Joel C. Hutcheson Abstract Aims Recent advances in genetic manipulation have allowed for over expression or deletion of selective genes in mice. This offers urologic investigators new means of understanding bladder function in the context of normal development or the response to outlet obstruction. It is important to correlate any genetic manipulations in mice with specific phenotypic properties such as voiding patterns, or muscle strip physiology. We describe a simple in vivo whole bladder preparation that may be used to study the phenotypic changes in bladder function. Methods Murine bladders were mounted on a 30 gauge needle and mounted in an organ chamber containing a physiologic buffer solution. Passive bladder properties were assessed with cystometry, and active contractile responses were measured in response to electrical field stimulation and agonists. The effects of hypoxia were also studied. Results Compliance in the murine bladder is dependent upon actin myosin interactions, and increased in the presence of calcium free buffer and EGTA. The sarcoplasmic reticulum plays a smaller role in the contraction of murine bladder than in other species. Murine bladder smooth muscle demonstrated a remarkable ability to withstand hypoxia. Conclusions This simple model can be adapted to help study the murine bladder smooth muscle phenotype under highly controlled circumstances. © 2004 Wiley-Liss, Inc. [source] Chapter 6: Maize with Increased Lysine (Lysine Maize,LY038)COMPREHENSIVE REVIEWS IN FOOD SCIENCE AND FOOD SAFETY, Issue 1 2008Article first published online: 30 JAN 200 ABSTRACT:, Data and information provided in this case study relate to a crop derived by modern biotechnology, in which a specific nutrient (lysine) has been increased in maize grain.Lysine maize is a feed ingredient with enhanced nutritional characteristics for poultry and swine and provides an alternative to adding supplemental lysine to diets for these animals. Lysine maize is in an advanced state of development; therefore, extensive unpublished data and information are presented to demonstrate that (1) Lysine maize,and the feeds and foods derived from it,are as safe as those derived from conventional maize,and (2) the increased lysine in Lysine maize grain produces the intended nutritional benefit for broiler chickens when compared to a diet containing conventional maize grain and a crystalline lysine supplement. These conclusions are based on a detailed molecular characterization of Lysine maize,a safety assessment of the introduced protein,a safety and nutritional assessment of the LY038 crop,and a comparison of the agronomic and phenotypic properties of maize hybrids with and without the Lysine maize trait. Although Lysine maize is a specialty crop for use in animal feed,its safety for both animals and humans must be demonstrated. Free lysine is significantly increased in Lysine maize by the introduction of the dapA gene (cordapA) from Corynebacterium glutamicum that encodes a form of dihydrodipicolinate synthase (cDHDPS) that is insensitive to lysine feedback inhibition.Analysis of lysine anabolic and catabolic pathways in maize identified 6 metabolites that might change as a consequence of the introduction of cDHDPS insensitive to lysine-feedback inhibition. The results of compositional analysis demonstrated that Lysine maize grain is comparable to conventional maize, with the exception of the intended increase in lysine and a corresponding increase in 2 products of lysine catabolism,saccha-ropine and -aminoadipic acid. Therefore, the safety and/or nutritional implication of these 3 compounds under the conditions of use were the focus of additional assessments and found to not present either a safety or nutritional problem. [source] | |||||||||||||