Research Interests: Genetics, Plant Biology, Biology, RNA silencing, Plant Molecular Biology, and 11 moreMedicine, RNA interference, Base Sequence, Transgenic plant, RNA Virus, double-stranded RNA, Biochemistry and cell biology, Plant Leaves, Transcriptional gene silencing (TGS), Molecular Sequence Data, and Cassava mosaic disease
DNA geminiviruses are thought to be targets of RNA silencing. Here, we characterize small interfering (si) RNAs—the hallmarks of silencing—associated with Cabbage leaf curl begomovirus in Arabidopsis ...
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... Bonneville, et al, 1989 J Bonneville, H Sanfaçon, J Fütterer and T Hohn, Post-transcriptional trans-activation in cauliflower mosaic virus ... Jackson and Kaminski, 1995 RJ Jackson and A Kaminski, Internal initiation of translation in... more
... Bonneville, et al, 1989 J Bonneville, H Sanfaçon, J Fütterer and T Hohn, Post-transcriptional trans-activation in cauliflower mosaic virus ... Jackson and Kaminski, 1995 RJ Jackson and A Kaminski, Internal initiation of translation in eukaryotes: the pcornavirus paradigm and beyond ...
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Sphingosine 1-phosphate (S1P) has many important roles in mammalian cells, including contributing to the control of cell survival and proliferation. S1P is generated by sphingosine kinases (SKs), of which two mammalian isoforms have been... more
Sphingosine 1-phosphate (S1P) has many important roles in mammalian cells, including contributing to the control of cell survival and proliferation. S1P is generated by sphingosine kinases (SKs), of which two mammalian isoforms have been identified (SK1 and SK2). To gain a better understanding of SK regulation, we have used a yeast two-hybrid screen to identify SK1-interacting proteins and established elongation factor 1A (eEF1A) as one such protein that associates with both SK1 and SK2. We show the direct interaction of eEF1A with the SKs in vitro, whereas the physiological relevance of this association was demonstrated by co-immunoprecipitation of the endogenous proteins from cell lysates. Although the canonical role of eEF1A resides in protein synthesis, it has also been implicated in other roles, including regulating the activity of some signaling enzymes. Thus, we examined the potential role of eEF1A in regulation of the SKs and show that eEF1A is able to directly increase the activity of SK1 and SK2 approximately 3-fold in vitro. Substrate kinetics demonstrated that eEF1A increased the catalytic rate of both SKs, while having no observable effect on substrate affinities of these enzymes for either ATP or sphingosine. Overexpression of eEF1A in quiescent Chinese hamster ovary cells increased cellular SK activity, whereas a small interfering RNA-mediated decrease in eEF1A levels in MCF7 cells substantially reduced cellular SK activity and S1P levels, supporting the in vivo physiological relevance of this interaction. Thus, this study has established a novel mechanism of regulation of both SK1 and SK2 that is mediated by their interaction with eEF1A.
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A region of the cauliflower mosaic virus genome was found to direct the expression of a nucleic-acid-binding protein in Escherichia coli. This protein is apparently toxic for the bacteria and leads to a destabilization of plasmids... more
A region of the cauliflower mosaic virus genome was found to direct the expression of a nucleic-acid-binding protein in Escherichia coli. This protein is apparently toxic for the bacteria and leads to a destabilization of plasmids containing that region. Antisense RNA was used to diminish the unwanted expression and to stabilize the respective recombinant plasmids. The approach described may prove useful in other cases where problems with cloning of eukaryotic DNA arise.