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41.
42.
The self-incompatibility phenotype in brassica is altered by the transformation of a mutant S locus receptor kinase 总被引:2,自引:0,他引:2 下载免费PDF全文
The self-incompatible (SI) Brassica napus line W1, which carries the 910 S allele, was transformed with an inactive copy of the 910 S locus receptor kinase (SRK) gene. Two transformed lines were analyzed based on their heritable ability to set self-seed. The first line was virtually completely self-compatible (SC), and reciprocal pollinations with the original W1 line demonstrated that only the stigma side of the SI phenotype was altered. An analysis of the expression of endogenous SRK-910 demonstrated that the mechanism of transgene action is via gene suppression. Furthermore, the expression of the S locus glycoprotein gene present in the 910 allele (SLG-910), SLG-A10, which is derived from a nonfunctional S allele, and an S locus-related gene were also suppressed. When the transgene was crossed into another SI line carrying the A14 S allele, it was also capable of suppressing the expression of the endogenous genes and of making this line SC. The second transgenic line studied was only partly SC. In this case as well, only the stigma phenotype was affected, although no gene suppression was detected for endogenous SRK-910 or SLG-910. In this line, the expression of the transgene most likely was causing the change in phenotype, and no effect was observed when this transgene was crossed into the other SI line. Therefore, this work reinforces the hypothesis that the SRK gene is required, but only for the stigma side of the SI phenotype, and that a single transgene can alter the SI phenotype of more than one S allele. 相似文献
43.
DR. JOHN LEE 《The Journal of eukaryotic microbiology》1993,40(4):395-410
ABSTRACT. Many advances have been made in our knowledge of the biology of foraminifera over the past several decades. Fine structural, biophysical, and molecular biological studies have shown that the most prominent components of their distinctive bidirectional granuloreliculopods are bundles of micro tubules linked by crossbridges to each other, as well as to membrane-bound organelles and the plasma membrane. the microtubules ratchet past each other as dynein transduces the free energy of ATP to produce pseudopodal movements. In spite of the fact that there are over 40,000 described species of living and fossil species of foraminifera, there have been many recent exciting discoveries of new species and groups. New casting techniques are providing us with greater understanding of the complexities and functional aspects of form in the group. Significant advances are being made in understanding the distribution and energetics of deep-sea forms. Larger and planktonic foraminifera are the hosts for a particularly diverse range of endosymbiotic algae, including dinoflagellates, chlorophytes, unicellular rhodophytes, and diatoms. Chloroplast husbandry also occurs. Significant research effort has been expended yielding us considerable insight into various aspects of the endosymbiotic phenomenon. A unified conceptual framework has been drawn to help us understand the life cycle options found in foraminifera. 相似文献
44.
Russell L Legg Jessica R Tolman Cameron T Lovinger Edwin D Lephart Kenneth DR Setchell Merrill J Christensen 《Reproductive biology and endocrinology : RB&E》2008,6(1):57
Background
High dietary intake of selenium or soybean isoflavones reduces prostate cancer risk. These components each affect androgen-regulated gene expression. The objective of this work was to determine the combined effects of selenium and isoflavones on androgen-regulated gene expression in rat prostate. 相似文献45.
Hasmik Keshishian E Robert McDonald III Filip Mundt Randy Melanson Karsten Krug Dale A Porter Luke Wallace Dominique Forestier Bokang Rabasha Sara E Marlow Judit JaneValbuena Ellen Todres Harrison Specht Margaret Lea Robinson Pierre M Jean Beltran Ozgun Babur Meagan E Olive Javad Golji Eric Kuhn Michael Burgess Melanie A MacMullan Tomas Rejtar Karen Wang DR Mani Shankha Satpathy Michael A Gillette William R Sellers Steven A Carr 《Molecular systems biology》2021,17(9)
Reliable methods to quantify dynamic signaling changes across diverse pathways are needed to better understand the effects of disease and drug treatment in cells and tissues but are presently lacking. Here, we present SigPath, a targeted mass spectrometry (MS) assay that measures 284 phosphosites in 200 phosphoproteins of biological interest. SigPath probes a broad swath of signaling biology with high throughput and quantitative precision. We applied the assay to investigate changes in phospho‐signaling in drug‐treated cancer cell lines, breast cancer preclinical models, and human medulloblastoma tumors. In addition to validating previous findings, SigPath detected and quantified a large number of differentially regulated phosphosites newly associated with disease models and human tumors at baseline or with drug perturbation. Our results highlight the potential of SigPath to monitor phosphoproteomic signaling events and to nominate mechanistic hypotheses regarding oncogenesis, response, and resistance to therapy. 相似文献
46.
Lihong?BuEmail author Kenneth?DR?Setchell Edwin?D?Lephart 《Reproductive biology and endocrinology : RB&E》2005,3(1):58
Background
Isoflavones, the most abundant phytoestrogens in soy foods, are structurally similar to 17beta-estradiol. Few studies have examined the nociception and stress hormone responses after consumption of soy isoflavones. 相似文献47.
DR Suresh Vamseedhar Annam K Pratibha BV Maruti Prasad 《Journal of biomedical science》2009,16(1):61-4
Background
Oxidative stress induced by the production of reactive oxygen species may play a critical role in the stimulation of HIV replication and the development of immunodeficiency. This study was conducted as there are limited and inconclusive studies on the significance of a novel early marker of oxidative stress which can reflect the total antioxidant capacity in HIV patients, 相似文献48.
Thirty-four cytochrome P-450 sequences from one bacterial and six
vertebrate species have been aligned with the aid of a computer alignment
algorithm. Phylogenetic trees were constructed using the
unweighted-pair-group and neighbor-joining methods. The two trees differed
at only a single branch point near the base of the tree. The cytochrome
P-450 superfamily of proteins clustered into eight families and contained
16 gene-duplication events. The first gene duplication occurred
approximately 1,360 Myr before the present (Mybp) and gave rise to
cytochrome P-450s found in two different cellular organelles, the
mitochondria and the endoplasmic reticulum. Both groups utilize cholesterol
or its metabolites as substrates, implying that cholesterol existed greater
than 1,360 Mybp. The fourth gene duplication (approximately 900 Mybp) gave
rise to the drug-metabolizing P-450s. These proteins aid in the
detoxification of foreign chemicals, as opposed to the metabolism of
endogenous compounds. The importance of the capacity to metabolize drugs is
reflected in 11 further gene duplications occurring in this lineage. The
first occurred approximately 800 Mybp and gave rise to the two major P-450
families, the phenobarbital and 3-methylcholanthrene families. An apparent
increase in the rate of cytochrome P-450 evolution is noted between the
bird-mammal divergence (300 Mybp) and the mammalian radiation (75 Mybp).
相似文献
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