The self-incompatibility phenotype in brassica is altered by the transformation of a mutant S locus receptor kinase

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.     

“On A Piece of Chalk”-Updated1

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.     

Docosahexaenoic acid is neither synthesized nor retroconverted by the normal and tumor mouse mammary epithelial cells in primary culture

Metabolism of 1-14C-[18:3(n-3)] and 1-14C-[22:6(n-3)] were investigated in the primary cultures of normal and tumor mouse mammary epithelial cells. Analysis of endogenous fatty acid composition indicated a decreased proportion of total (n-6) PUFA in the cultured tumor cells compared to normal cells. These cells can synthesize significant amount of 20:5 (n-3) and 22:5 (n-3) but not 22:6 (n-3), from 18:3 (n-3). There was very little or no retroconversion of 22:6 (n-3) by these cells. It has been concluded that mammary epithelial cells may be deficient in 4-desaturase activity and also that exogenous 22:6 (n-3), instead of serving as a source of 20:5 (n-3), may actually counter the effects of both 20:4 (n-6) and 20:5 (n-3) in the mammary tissue.     

Diets high in selenium and isoflavones decrease androgen-regulated gene expression in healthy rat dorsolateral prostate

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.     

A highly multiplexed quantitative phosphosite assay for biology and preclinical studies

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.     

Influences of dietary soy isoflavones on metabolism but not nociception and stress hormone responses in ovariectomized female rats

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.     

Mapping of transposable element<Emphasis Type="Italic"> Dissociation</Emphasis> inserts in<Emphasis Type="Italic"> Brassica oleracea</Emphasis> following plant regeneration from streptomycin selection of callus

To investigate the potential of heterologous transposons as a gene-tagging system in broccoli (Brassica oleracea var. italica), we have introduced a Dissociation (Ds)-based two-element transposon system. Ds has been cloned into a 35S-SPT excision-marker system, with transposition being driven by an independent 35S-transposase gene construct. In three successive selfed generations of plants, there was no evidence of germinal-excision events. In a previous study, we overcame this apparent inability to produce B. oleracea plants with germinal excisions by performing a novel tissue-culture technique to select for fully green shoots from seed with somatic excision events. The results showed a very high efficiency of regeneration of fully green plants (up to 65%), and molecular analysis showed that the plants contained the equivalent of a germinal-excision event. In this study, we followed the previous work by using inverse and nested PCR to generate probes of flanking genomic DNA adjacent to independently reinserted Ds elements, and these were hybridised to DNA from a double-haploid mapping population of B. oleracea. Seventeen Ds insertions and the original Ds T-DNA site have been localised, and these are spread over six (out of nine) linkage groups. Distribution of inserts show that 15 were found on a different linkage group to the original launch site, and of these 11 were found to be clustered on two separate groups. Previous studies in other plant species have found that germinal excision of Ds predominantly moves to sites linked close to the donor site. However, this study shows a potential to produce plants with Ds insertion scattered over many unlinked sites.Comunicated by C. Möllers     

Total antioxidant capacity – a novel early bio-chemical marker of oxidative stress in HIV infected individuals

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,