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991.
992.
Nagy ZT  Sonet G  Glaw F  Vences M 《PloS one》2012,7(3):e34506

Background

DNA barcoding of non-avian reptiles based on the cytochrome oxidase subunit I (COI) gene is still in a very early stage, mainly due to technical problems. Using a newly developed set of reptile-specific primers for COI we present the first comprehensive study targeting the entire reptile fauna of the fourth-largest island in the world, the biodiversity hotspot of Madagascar.

Methodology/Principal Findings

Representatives of the majority of Madagascan non-avian reptile species (including Squamata and Testudines) were sampled and successfully DNA barcoded. The new primer pair achieved a constantly high success rate (72.7–100%) for most squamates. More than 250 species of reptiles (out of the 393 described ones; representing around 64% of the known diversity of species) were barcoded. The average interspecific genetic distance within families ranged from a low of 13.4% in the Boidae to a high of 29.8% in the Gekkonidae. Using the average genetic divergence between sister species as a threshold, 41–48 new candidate (undescribed) species were identified. Simulations were used to evaluate the performance of DNA barcoding as a function of completeness of taxon sampling and fragment length. Compared with available multi-gene phylogenies, DNA barcoding correctly assigned most samples to species, genus and family with high confidence and the analysis of fewer taxa resulted in an increased number of well supported lineages. Shorter marker-lengths generally decreased the number of well supported nodes, but even mini-barcodes of 100 bp correctly assigned many samples to genus and family.

Conclusions/Significance

The new protocols might help to promote DNA barcoding of reptiles and the established library of reference DNA barcodes will facilitate the molecular identification of Madagascan reptiles. Our results might be useful to easily recognize undescribed diversity (i.e. novel taxa), to resolve taxonomic problems, and to monitor the international pet trade without specialized expert knowledge.  相似文献   
993.
We report a new approach for molecular sex identification of extant Ursinae and Tremarctinae bears. Two Y‐specific fragments (SMCY and 318.2) and one X‐specific fragment (ZFX) are amplified in a multiplex PCR, yielding a double test for male‐specific amplification and an internal positive control. The primers were designed and tested to be bear‐specific, thereby minimizing the risk of cross‐amplification in other species including humans. The high sensitivity and small amplicon sizes (100, 124, 160 base pairs) facilitate analysis of non‐invasively obtained DNA material. DNA from tissue and blood as well as from 30 non‐invasively collected hair and faeces yielded clear and easily interpretable results. The fragments were detected both by standard gel electrophoresis and automated capillary electrophoresis.  相似文献   
994.
995.
The major light-harvesting complex of Amphidinium (A.) carterae, chlorophyll-a–chlorophyll-c 2–peridinin–protein complex (acpPC), was studied using ultrafast pump-probe spectroscopy at low temperature (60 K). An efficient peridinin–chlorophyll-a energy transfer was observed. The stimulated emission signal monitored in the near-infrared spectral region was stronger when redder part of peridinin pool was excited, indicating that these peridinins have the S1/ICT (intramolecular charge-transfer) state with significant charge-transfer character. This may lead to enhanced energy transfer efficiency from “red” peridinins to chlorophyll-a. Contrary to the water-soluble antenna of A. carterae, peridinin–chlorophyll-a protein, the energy transfer rates in acpPC were slower under low-temperature conditions. This fact underscores the influence of the protein environment on the excited-state dynamics of pigments and/or the specificity of organization of the two pigment–protein complexes.  相似文献   
996.
997.
The lipid-containing membrane of Rauscher murine leukemia virus was studied using stearic acid spin labels with the nitroxide ring on the C5 and C16 positions. The environment of the C5 spin label was found to be much more rigid than that of the C16 spin label. This result, which parallels similar observations in red cell membranes and influenza virus, suggests that the lipid phase of Rauscher murine leukemia virus is arranged in a bilayer.  相似文献   
998.
Measurements of the triplet state zero-field splitting and intersystem crossing rate constants for isolated bacteriochlorophyll a and for chemically reduced photosynthetic bacteria are utilized to investigate the geometry of the bacteriochlorophyll dimer in the reaction center.  相似文献   
999.
Wild barley, Hordeum vulgare spp. spontaneum, has a wider genetic diversity than its cultivated progeny, Hordeum vulgare spp. vulgare. Osmotic stress leads to a series of different responses in wild barley seminal roots, ranging from no changes in suberization to enhanced endodermal suberization of certain zones and the formation of a suberized exodermis, which was not observed in the modern cultivars studied so far. Further, as a response to osmotic stress, the hydraulic conductivity of roots was not affected in wild barley, but it was 2.5-fold reduced in cultivated barley. In both subspecies, osmotic adjustment by increasing proline concentration and decreasing osmotic potential in roots was observed. RNA-sequencing indicated that the regulation of suberin biosynthesis and water transport via aquaporins were different between wild and cultivated barley. These results indicate that wild barley uses different strategies to cope with osmotic stress compared with cultivated barley. Thus, it seems that wild barley is better adapted to cope with osmotic stress by maintaining a significantly higher hydraulic conductivity of roots during water deficit.  相似文献   
1000.
Abstract

Three new appropriately protected phosphoramidites have been synthesized. Two of them (1 and 2) are isosteric to that of inosine (3) [1], one is a derivative of 1′3-propanediol (4). Whereas the inosine isosteres contain an ambiguous base recognizing adenine, guanine as well as cytosine residues in double stranded DNA-fragments the 1,3-propanediol unit can be seen as a simple nucleoside substitute in a DNA chain. It contains only those structural elements necessary to form the sugar/phosphate backbone, without supplying the DNA with either a base [21 or a 2′-deoxyribofuranosyl moiety.  相似文献   
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