14C-Amino acid incorporating activity in the absence of exogenous mRNA was found in a cell-free system from embryos of light-germinated Pinus thunbergii seeds, but not in that from dark-imbibed seed embryos. Template activity in the cell-free system from the light-germinated seed embryos was observed in the ribosome fraction, especially the polyribosome fraction, but not in the 100,000×g supernatant fraction (s100). These facts suggest that the nature of the block in protein synthesis during the imbibition of seeds in the dark is due to the lack or inactivity of mRNA. The s100 from light-germinated seed embryos was found to be less active in amino acid incorporation than that from dark-imbibed seed embryos.
Journal Article Nucleotide Sequence of cDNA Encoding the Small Subunit of Ribolose-1,5-Bisphosphate Carboxylase from Maize Get access Makoto MATSUOKA, Makoto MATSUOKA *National Institute of Agrobiological ResourcesTsukuba Science City, Yatabe, Ibaraki 305 Search for other works by this author on: Oxford Academic PubMed Google Scholar Yuriko KANO-MURAKAMI, Yuriko KANO-MURAKAMI **Fruit Tree Research StationTsukuba Science City, Yatabe, Ibaraki 305 Search for other works by this author on: Oxford Academic PubMed Google Scholar Yoshiyuki TANAKA, Yoshiyuki TANAKA ***National Institute of Agro-Environmental ScienceTsukuba Science City, Yatabe, Ibaraki 305 Search for other works by this author on: Oxford Academic PubMed Google Scholar Yoshihiro OZEKI, Yoshihiro OZEKI ****Department of Biology, College of Arts and Science, The University of TokyoMeguro-ku, Tokyo 153 Search for other works by this author on: Oxford Academic PubMed Google Scholar Naoki YAMAMOTO Naoki YAMAMOTO *****Forestry and Forest Products Research Institute,Tsukuba Science City, Yatabe, Ibaraki 305 Search for other works by this author on: Oxford Academic PubMed Google Scholar The Journal of Biochemistry, Volume 102, Issue 4, October 1987, Pages 673–676, https://doi.org/10.1093/oxfordjournals.jbchem.a122103 Published: 01 October 1987 Article history Received: 02 July 1987 Published: 01 October 1987
Abstract Rhizoctonia solani AG‐1 IA causes a necrotrophic rice disease and is a serious threat to rice production. To date, only a few effectors have been characterized in AG‐1 IA. We previously identified RsIA_CtaG/Cox11 and showed that infiltration of the recombinant protein into rice leaves caused disease‐like symptoms. In the present study, we further characterized the functionality of RsIA_CtaG/Cox11. RsIA_CtaG/Cox11 is an alternative transcript of cytochrome c oxidase copper chaperone Cox11 that starts from the second AUG codon, but contains a functional secretion signal peptide. RNA interference with RsIA_CtaG/Cox11 reduced the pathogenicity of AG‐1 IA towards rice and Nicotiana benthamiana without affecting its fitness or mycelial morphology. Transient expression of the RsIA_CtaG/Cox11‐GFP fusion protein demonstrated the localization of RsIA_CtaG/Cox11 to mitochondria. Agro‐infiltration of RsIA_CtaG/Cox11 into N. benthamiana leaves inhibited cell death by BAX and INF1. In contrast to rice, agro‐infiltration of RsIA_CtaG/Cox11 did not induce cell death in N. benthamiana . However, cell death was observed when it was coinfiltrated with Os_CoxVIIa , which encodes a subunit of cytochrome c oxidase. Os_CoxVIIa appeared to interact with RsIA_CtaG/Cox11. The cell death triggered by coexpression of RsIA_CtaG/Cox11 and Os_CoxVIIa is independent of the leucine‐rich repeat receptor kinases BAK1/SOBIR1 and enhanced the susceptibility of N. benthamiana to AG‐1 IA. Two of the three evolutionarily conserved cysteine residues at positions 25 and 126 of RsIA_CtaG/Cox11 were essential for its immunosuppressive activity, but not for cell death induction. This report suggests that RsIA_CtaG/Cox11 appears to have a dual role in immunosuppression and cell death induction during pathogenesis.
Polymerase chain reaction (PCR) is a powerful tool for clinical diagnosis in the field of oncology, infection, and allergy. However, a simple and sensitive method for quantifying PCR products has not been established. We therefore used a novel fluorescence DNA intercalator, pyrylium iodide (P2) to quantify PCR products. A 838-bp fragment of the human beta-actin gene and a 374-bp fragment of the gene for ornithine decarboxylase (ODC) and ODC primer dimers were generated by PCR and quantified using either P2 or another fluorescence DNA intercalator, YOYO-1. In addition, utilizing RT-PCR and the P2 method, the ODC mRNA expression from 10 colonic cancers was quantified. Serially diluted beta-actin and ODC PCR products could be quantified using P2 without having to separate them from primer dimers and other components of the reaction mixture. However, YOYO-1 could not be used to quantify the PCR products because of high background fluorescence from the primer dimers. In the clinical study, ODC mRNA expression as quantified by P2 was significantly higher in cancerous tissue (113.8 +/- 4.1; mean +/- SEM; plate reader units) than in mucosa of normal appearance (68.4 +/- 4.8). P2 is a promising tool for quantifying PCR products.
