InBrassica, self-incompatibility (SI) can be overcome by CO2 application, an effective method for obtaining numerous inbred lines for F, commercial seed. We previously reported two different
S-alleles ofBrassica campestris, S733 and S734, with extremely different degrees of susceptibility to this gas. In the current study, we raised a cross-population between
those two genetic lines, and analyzed their reaction level of self-incompatibility to CO2 (RLSICO2). Here, all 40 of our progeny from the F1 cross-population were susceptible, maintaining high values of RLSICO2. This suggests that the susceptible line, S734, is dominant to the insusceptible line, S733. We also generated an F2 selfing-population of each crossed progeny, S733♀ S734♂ and S733♂ S734♀, to assess the RLSICO2 of each individual. PCR-RFLP analysis was performed to determine the S-genotype of the F2 population. The S734 allele segregated in a theoretical ratio of the dominant trait, and the RLSICO2 was consistent with the dominance relationship. Therefore, we have now demonstrated that high RLSICO2 in β.campestris is controlled by a dominant gene.
Both authors contributed equally to this work 相似文献
Activation of the MET tyrosine kinase receptor by hepatocyte growth factor/scatter factor is classically associated with cell survival. Nonetheless, stress stimuli can lead to a caspase-dependent cleavage of MET within its juxtamembrane region, which generate a proapoptotic 40 kDa fragment (p40 MET). We report here that p40 MET is in fact generated through an additional caspase cleavage of MET within its extreme C-terminal region, which removes only few amino acids. We evidenced a hierarchical organization of these cleavages, with the C-terminal cleavage favoring the juxtamembrane one. As a functional consequence, the removal of the last amino acids of p40 MET increases its apoptotic capacity. Finally, cells expressing a MET receptor mutated at the C-terminal caspase site are unable to generate p40 MET and are resistant to apoptosis, indicating that generation of p40 MET amplifies apoptosis. These results revealed a two-step caspase cleavage of MET resulting in the reshaping of this survival receptor to a proapoptotic factor. 相似文献
SUMMARY: Estimation of kinetic parameters in a biochemical pathway or network represents a common problem in systems studies of biological processes. We have implemented a C library, named libSRES, to facilitate a fast implementation of computer software for study of non-linear biochemical pathways. This library implements a (mu, lambda)-ES evolutionary optimization algorithm that uses stochastic ranking as the constraint handling technique. Considering the amount of computing time it might require to solve a parameter-estimation problem, an MPI version of libSRES is provided for parallel implementation, as well as a simple user interface. libSRES is freely available and could be used directly in any C program as a library function. We have extensively tested the performance of libSRES on various pathway parameter-estimation problems and found its performance to be satisfactory. AVAILABILITY: The source code (in C) is free for academic users at http://csbl.bmb.uga.edu/~jix/science/libSRES/ 相似文献
Morphological comparison, cytogenetic study and fertility analysis of Hystrix
duthiei (2n = 28) from China, Hystrix longearistata (2n= 28) from Japan and their artificial hybrids were carried out. Morphologically H. duthiei was similar to H. longearistata.
H. longearistata had longer lemma awn, wider leaf and 2~3 florets per spikelet, while H.
duthiei had 1~2 florets per spikelet. These two taxa can be easily crossed. Fl hybrids
showed very high degree of bivalent pairing (13~14 bivalents) at the metaphase- I of meiosis. No multivalents were found. The fertility of pollen and seed set of the parents were normal, while the Fl hybrids were of only partial fertility. H. longearistata was closely related
to H. duthiei. They should be included in the same species. Because of the differences of
their distributions and habitats, some morphological divergency and a little sterility barrier
have had appeared between them. It is reasonable to treat Hystrix longearistata as a sub-species of Hystrix duthiei . 相似文献
The observation of Scanning Electron Microscope (SEM) shows that a tibia bone is a kind of bioceramic composite consisting of hydroxyapatite layers and collagen protein matrix. All the hydroxyapatite layers are parallel with the surface of the bone and consist of numerous hydroxyapatite sheets. The observation also shows that there is a kind of intercrossed microstructure of the hydroxyapatite sheets. In this kind of microstructure, the hydroxyapatite sheets in an arbitrary hydroxyapatite layer make a large intercrossed angle with the hydroxyapatite sheets in their adjacent hydroxyapatite layers. The maximum pullout force of the intercrossed microstructure, which is closely related to the fracture toughness of the bone, is investigated and compared with that of the parallel microstructure of the sheets through their representative models. The result of the investigation indicates that the maximum pullout force of the intercrossed microstructure is markedly larger than that of the parallel microstructure, which is experimentally verified. 相似文献
Accumulated evidence demonstrated that an elevated plasma homocysteine level, hyperhomocysteinemia, induced cognitive impairment in animals, elderly and the patients with neurodegenerative diseases. To date, the underlying cellular and molecular mechanisms by which hyperhomocysteinemia induces cognitive impairment has not been clearly defined. The purpose of this study was to investigate the possible cellular and molecular mechanisms behind hyperhomocysteinemia signaling in rat memory impairment. The results from this study demonstrated that hyperhomocysteinemia induced neuronal damage and loss in hippocampal CA3 region and downregulated the cAMP response element-binding protein (CREB) phosphorylation. The findings of this study provide evidence that hyperhomocysteinemia induces rat memory impairment via injuring hippocampal CA3 neurons and downregulating CREB phosphorylation.