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991.
992.
Female Cycnotrachelus roelofsi (Coleoptera: Attelabidae) construct two types of leaf roll, i.e., cut-off cradles (CCs) and suspended cradles (SCs), in which
to lay eggs; these cradles are generally constructed using older and younger leaves, respectively. We conducted two experiments
to determine whether the quality of cradle leaves affects egg and larval survival. In the first experiment, we severed all
SCs from a tree and placed them on the ground with unmanipulated CCs in the early breeding season. In the second experiment,
we resuspended all CCs in a tree with unmanipulated SCs in the late breeding season. We also compared leaf mass per area (LMA),
polyphenol content, and nitrogen content between the two cradle types to determine whether there were any differences in leaf
quality. Larval mortality, probably caused by cradle herbivory, was significantly greater in severed SCs than in intact CCs
in the early season, suggesting that leaf quality had a profound effect on larval mortality in the terrestrial microhabitat.
In contrast, larval mortality did not differ between resuspended CCs and intact SCs in the late season, suggesting that leaf
quality had little effect on larval mortality in the arboreal microhabitat. LMA was higher in CCs than in SCs, but there were
no differences in the nitrogen and polyphenol contents. These results suggest that cradles constructed using mature, tough
leaves were more effective against terrestrial cradle herbivores than those constructed using new, soft leaves. 相似文献
993.
994.
Hagiwara D Matsubayashi Y Marui J Furukawa K Yamashino T Kanamaru K Kato M Abe K Kobayashi T Mizuno T 《Bioscience, biotechnology, and biochemistry》2007,71(3):844-847
We recently compiled a complete list of phosphorelay signal transduction components in the model filamentous fungus Aspergillus nidulans. In this study, we characterized a histidine protein kinase (designated NikA) that is found in many fungi, with special reference to responses to potent fungicides (iprodione and fludioxonil). We provided evidence that not only NikA, but also two downstream response regulators (SskA and SrrA) are crucially implicated in the mode of action of these fungicides, and also that the further downstream HogA-MAPK cascade is exaggerated abnormally (or ectopically) in hyphae by the fungicides in a manner dependent on the NikA-SskA phosphorelay. 相似文献
995.
Haploid sporophytes of Osmunda claytoniana (2n = x = 22) were apogamously produced from calli when cultivated on a hormone-free medium. Flow cytometric analysis showed that
ploidy chimeras were spontaneously produced in a haploid sporophyte of O. claytoniana and those of O. japonica that were obtained in the previous study. In the haploid sporophyte of O. claytoniana, a diploid pinnule and a partially diploid terminal segment were produced in a haploid pinna. In O. japonica, a haploid sporophyte yielded a diploid pinna in a haploid frond, and another haploid sporophyte yielded a diploid pinnule
in a haploid pinna. Diploid chimeras were large in size and could be readily distinguished from other haploid parts of the
fronds. It is likely that the chimeras were produced clonally from a single diploid cell that established chromosome doubling. 相似文献
996.
Hirayama Y Yamada T Oya Y Ito M Kato M Imaichi R 《Development genes and evolution》2007,217(5):363-372
STM (RaSTM) and YAB2 (RaYAB2) homologues were isolated from Ruscus aculeatus (Asparagaceae, monocots), and their expressions were analyzed by real-time polymerase chain reaction (PCR) to assess hypotheses on the evolutionary origin of the phylloclade in the Asparagaceae. In young shoot buds, RaSTM is expressed in the shoot apex, while RaYAB2 is expressed in the scale leaf subtending the shoot bud. This expression pattern is shared by other angiosperms, suggesting that the expression patterns of RaSTM and RaYAB2 are useful as molecular markers to identify the shoot and leaf, respectively. RaSTM and RaYAB2 are expressed concomitantly in phylloclade primordia. These results suggest that the phylloclade is not homologous to either the shoot or leaf, but that it has a double organ identity. 相似文献
997.
998.
A histone lysine methyltransferase activated by non-canonical Wnt signalling suppresses PPAR-gamma transactivation 总被引:4,自引:0,他引:4
999.
Background
There is a large amount of microarray data accumulating in public databases, providing various data waiting to be analyzed jointly. Powerful kernel-based methods are commonly used in microarray analyses with support vector machines (SVMs) to approach a wide range of classification problems. However, the standard vectorial data kernel family (linear, RBF, etc.) that takes vectorial data as input, often fails in prediction if the data come from different platforms or laboratories, due to the low gene overlaps or consistencies between the different datasets. 相似文献1000.