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21.
Longevity is a major characteristic of animals that has long fascinated scientists. In this work, we present a comprehensive database of animal longevity records and related life‐history traits entitled AnAge, which we compiled and manually curated from an extensive literature. AnAge started as a collection of longevity records, but has since been expanded to include quantitative data for numerous other life‐history traits, including body masses at different developmental stages, reproductive data such as age at sexual maturity and measurements of reproductive output, and physiological traits related to metabolism. AnAge features over 4000 vertebrate species and is a central resource for applying the comparative method to studies of longevity and life‐history evolution across the tree of life. Moreover, by providing a reference value for longevity and other life‐history traits, AnAge can prove valuable to a broad range of biologists working in evolutionary biology, ecology, zoology, physiology and conservation biology. AnAge is freely available online ( http://genomics.senescence.info/species/ ). 相似文献
22.
JORDAN KARUBIAN VICTORIA L. SORK TESSA ROORDA RENATA DURÃES THOMAS B. SMITH 《Molecular ecology》2010,19(8):1745-1753
As the dominant seed dispersal agents in many ecosystems, frugivorous animals profoundly impact gene movement and fine‐scale genetic structure of plants. Most frugivores engage in some form of destination‐based dispersal, in that they move seeds towards specific destinations, resulting in clumped distributions of seeds away from the source tree. Molecular analyses of dispersed seeds and seedlings suggest that destination‐based dispersal may often yield clusters of maternal genotypes and lead to pronounced local genetic structure. The long‐wattled umbrellabird Cephalopterus penduliger is a frugivorous bird whose lek mating system creates a species‐specific pattern of seed dispersal that can potentially be distinguished from background dispersal processes. We used this system to test how destination‐based dispersal by umbrellabirds into the lek affects gene movement and genetic structure of one of their preferred food sources Oenocarpus bataua, a canopy palm tree. Relative to background dispersal processes, umbrellabird mating behaviour yielded more diverse seed pools in leks that included on average five times more seed sources and a higher incidence of long‐distance dispersal events. This resulted in markedly lower fine‐scale spatial genetic structure among established seedlings in leks than background areas. These species‐specific impacts of destination‐based dispersal illustrate how detailed knowledge of disperser behaviour can elucidate the mechanistic link driving observed patterns of seed movement and genetic structure. 相似文献
23.
Feary DA Burt JA Bauman AG Usseglio P Sale PF Cavalcante GH 《Journal of fish biology》2010,77(8):1931-1947
To examine the role of climatic extremes in structuring reef fish communities in the Arabian region, reef fish communities were visually surveyed at four sites within the southern Persian Gulf (also known as the Arabian Gulf and The Gulf), where sea-surface temperatures are extreme (range: 12-35° C annually), and these were compared with communities at four latitudinally similar sites in the biogeographically connected Gulf of Oman, where conditions are more moderate (range: 22-31° C annually). Although sites were relatively similar in the cover and composition of coral communities, substantial differences in the structure and composition of associated fish assemblages were apparent. Fish assemblages in the southern Persian Gulf held significantly lower estimates of abundance, richness and biomass, with significantly higher abundances of smaller sized individuals than Gulf of Oman assemblages. Functionally, southern Persian Gulf sites held significantly lower abundances of nearly all the common fish trophic guilds found on Gulf of Oman sites, although higher abundances of herbivorous grazers were apparent. These results suggest the potential for substantial changes in the structure of reef-associated fish communities, independent of changes in habitat within an environment of increasing fluctuations in oceanic climate. 相似文献
24.
Robson Sartorello Alexandre Budu Piero Bagnaresi Carlos AH Fernandes Paloma M. Sato Vânia B. Bueno Marcos RM Fontes Pedro L. Oliveira Gabriela O. Paiva‐Silva Simone V. Alves Luis ES Netto Luiz H. Catalani Celia RS Garcia 《Cell biology international》2010,34(8):859-865
The cellular traffic of haem during the development of the human malaria parasite Plasmodium falciparum, through the stages R (ring), T (trophozoite) and S (schizonts), was investigated within RBC (red blood cells). When Plasmodium cultures were incubated with a fluorescent haem analogue, ZnPPIX (Zn protoporphyrin IX) the probe was seen at the cytoplasm (R stage), and the vesicle‐like structure distribution pattern was more evident at T and S stages. The temporal sequence of ZnPPIX uptake byP. falciparum‐infected erythrocytes shows that at R and S stages, a time‐increase acquisition of the porphyrin reaches the maximum fluorescence distribution after 60 min; in contrast, at the T stage, the maximum occurs after 120 min of ZnPPIX uptake. The difference in time‐increase acquisition of the porphyrin is in agreement with a maximum activity of haem uptake at the T stage. To gain insights into haem metabolism, recombinant PfHO (P. falciparum haem oxygenase) was expressed, and the conversion of haem into BV (biliverdin) was detected. These findings point out that, in addition to haemozoin formation, the malaria parasite P. falciparum has evolved two distinct mechanisms for dealing with haem toxicity, namely, the uptake of haem into a cellular compartment where haemozoin is formed and HO activity. However, the low Plasmodium HO activity detected reveals that the enzyme appears to be a very inefficient way to scavenge the haem compared with the Plasmodium ability to uptake the haem analogue ZnPPIX and delivering it to the food vacuole. 相似文献
25.
SORAYA C M LEAL-BERTIOLI ALETÉIA V PASCOAL PATRÍCIA M GUIMARÃES MARIA F GROSSI DE SÁ REJANE L GUIMARÃES DAMARES C MONTE DAVID J BERTIOLI 《The Annals of applied biology》2003,143(3):349-357
The protein Tarin 1, from Colocasia esculenta, was expressed in Nicotiana tabacum. Bioassays were done on plants expressing Tarin 1 at different levels using Spodoptera frugiperda larvae, various bacteria and fungi and the root‐knot nematode Meloidogyne javanica. It was found that S. frugiperda larvae fed on transformed plants had retarded and lower pupation, lower accumulated biomass and higher mortality rate than larvae fed on control plants. Also, Tarin 1 was found to inhibit the growth in vitro of Pseudomonas syringae pv. tomato. For Meloidogyne javanica, both relative replication and root damage were greater in control plants than in transformed plants, but the results were not statistically significant. This work illustrates the effects of plants expressing Tarin 1, on the growth and development of insects and bacteria, and shows its potential for pest management. 相似文献
26.
Clustering of mutations affecting central pathway enzymes of carbohydrate catabolism in Pseudomonas aeruginosa 总被引:10,自引:10,他引:0
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Whole metabolizing Brevibacterium linens cells were used to study the transport of aromatic amino acids. Kinetic results followed the Michaelis-Menten equation with apparent Km values for phenylalanine, tyrosine, and tryptophan of 24, 3.5, and 1.8 microM. Transport of these amino acids was optimum at pH 7.5 and 25 degrees C for phenylalanine and pH 8.0 and 35 degrees C for tyrosine and tryptophan. Crossed inhibitions were all noncompetitive. The only marked stereospecificity was for the L form of phenylalanine. Transport was almost totally inhibited by carbonyl cyanide-m-chlorophenylhydrazone. Iodoacetate and N-ethylmaleimide were much more inhibitory for tryptophan transport than for transport of the other two aromatic amino acids. 相似文献
27.
Eva?FreyhultEmail author Peteris?Prusis Maris?Lapinsh Jarl?ES?Wikberg Vincent?Moulton Mats?G?GustafssonEmail author 《BMC bioinformatics》2005,6(1):50
Background
Proteochemometrics is a new methodology that allows prediction of protein function directly from real interaction measurement data without the need of 3D structure information. Several reported proteochemometric models of ligand-receptor interactions have already yielded significant insights into various forms of bio-molecular interactions. The proteochemometric models are multivariate regression models that predict binding affinity for a particular combination of features of the ligand and protein. Although proteochemometric models have already offered interesting results in various studies, no detailed statistical evaluation of their average predictive power has been performed. In particular, variable subset selection performed to date has always relied on using all available examples, a situation also encountered in microarray gene expression data analysis. 相似文献28.
29.
Feary ES Juengel JL Smith P French MC O'Connell AR Lawrence SB Galloway SM Davis GH McNatty KP 《Biology of reproduction》2007,77(6):990-998
Woodlands sheep have a putative genetic mutation (FecX2(W)) that increases ovulation rate. At present, the identity of FecX2(W) is unknown. The trait does not appear to be due to the previously described mutations in bone morphogenetic protein 15 (BMP15), growth differentiation factor 9 (GDF9), or bone morphogenetic protein receptor type 1B (BMPR1B) that affect ovulation rate in sheep. Potentially, FecX2(W) could be an unidentified genetic mutation in BMP15 or in the closely related GDF9, which interacts with BMP15 to control ovarian function. Alternatively, FecX2(W) may affect ovulation rate by changing the expression patterns in the molecular pathways activated by genes known to regulate ovulation rate. The objectives of these experiments were to sequence the complete coding region of the BMP15 and GDF9 genes, determine the patterns of expression of mRNAs encoding GDF9, BMP15, TGFBR1, BMPR1B, and BMPR2 during follicular development, and characterize the follicular populations in ewes heterozygous for the Woodlands mutation and their wild-type contemporaries. No differences in the coding sequences of BMP15 or GDF9 genes were identified that were associated with enhanced ovulation rate. The expression patterns of GDF9 and BMPR2 mRNAs were not different between genotypes. However, expression of BMP15 mRNA was less in oocytes of FecX2(W) ewes in large preantral and antral follicles. Expression of ALK5 mRNA was significantly higher in the oocytes of FecX2(W) ewes, whereas expression of BMPR1B was decreased in both oocytes and granulosa cells of FecX2(W) ewes. FecX2(W) ewes also had increased numbers of antral follicles <1 mm in diameter. These follicles were smaller in average diameter, with the oocytes also being of a smaller mean diameter. Given that a mutation in BMP15 or BMPR1B results in increased ovulation rates in sheep, the differences in expression levels of BMP15 and BMPR1B may play a role in the increase in ovulation rate observed in Woodlands ewes with the FecX2(W) mutation. 相似文献
30.
XMPP for cloud computing in bioinformatics supporting discovery and invocation of asynchronous web services 总被引:1,自引:0,他引:1