Isolation of 48 genetic markers appropriate for high throughput genotyping of inbred rat strains by B1 repetitive sequence-representational difference analysis

Mapping of genetic suppressors, modifiers, and quantitative trait loci (QTLs) requires genetic markers that can be efficiently and inexpensively genotyped for a large number of individuals. To isolate rat genetic markers suitable for this purpose, representational difference analysis (RDA) was performed with amplicons prepared by PCR with the B1 repetitive sequence used as the primer (B1-amplicons). In total, 48 polymorphic DNA fragments were isolated by five series of RDA, subtracting the B1-amplicons prepared from an ACI/N (ACI) rat from those prepared from BUF/Nac (BUF), and vice versa. All the polymorphic fragments detected ``presence-or-absence' polymorphisms with B1-amplicons prepared from ACI, BUF, and their F₂ progeny, and each fragment was linkage mapped. Dot-blotting amplicons onto filters at a high density and hybridization of the filters with these B1-RDA markers made it possible to genotype a large number of rats simultaneously for multiple loci. These B1-RDA markers were polymorphic between two given inbred strains of rat at frequencies between 30% and 70%. This is the first report on the isolation of B1-RDA markers among inbred strains of rats. Received: 15 July 1998 / Accepted: 18 August 1998     

Vegetative compatibility of an isolate ofVerticillium dahliae pathogenic to both tomato and pepper

An isolate ofVerticillum dahliae Vdp-4, pathogenic to both tomato and pepper (tomato-pepper pathotype), was examined for its vegetative compatibility with testers of the Japanese vegetative compatibility group (subgroups J1, J2, and J3). Seven isolates ofV. dahliae from the same field as Vdp-4 in Misato, Nagano Pref. and two isolates from Hokkaido were separately determined as either tomato pathotype (B) or pepper pathotype (C). Isolate 5922 previously reported as tomato-pepper pathotype was also examined. Compatiblenit1 and NitM mutants were obtained from all isolates except for isolates Vdp-3 and Vdt-10. The isolate of tomato-pepper pathotype Vdp-4 showed a strong reaction with VCGJ1 and J3 and was thus assigned to J3. Seven of these isolates showed compatibility and were assigned into three provisional subgroups. The isolate 5922 was self-incompatible.     

Oligodendrocyte Progenitor Cells Directly Utilize Lactate for Promoting Cell Cycling and Differentiation

Oligodendrocyte progenitor cells (OPCs) undergo marked morphological changes to become mature oligodendrocytes, but the metabolic resources for this process have not been fully elucidated. Although lactate, a metabolic derivative of glycogen, has been reported to be consumed in oligodendrocytes as a metabolite, and to ameliorate hypomyelination induced by low glucose conditions, it is not clear about the direct contribution of lactate to cell cycling and differentiation of OPCs, and the source of lactate for remyelination. Therefore, we evaluated the effect of 1,4‐dideoxy‐1,4‐imino‐d‐arabinitol (DAB), an inhibitor of the glycogen catabolic enzyme glycogen phosphorylase, in a mouse cuprizone model. Cuprizone induced demyelination in the corpus callosum and remyelination occurred after cuprizone treatment ceased. This remyelination was inhibited by the administration of DAB. To further examine whether lactate affects proliferation or differentiation of OPCs, we cultured mouse primary OPC‐rich cells and analyzed the effect of lactate. Lactate rescued the slowed cell cycling induced by 0.4 mM glucose, as assessed by the BrdU‐positive cell ratio. Lactate also promoted OPC differentiation detected by monitoring the mature oligodendrocyte marker myelin basic protein, in the presence of both 36.6 mM and 0.4 mM glucose. Furthermore, these lactate‐mediated effects were suppressed by the reported monocarboxylate transporter inhibitor, α‐cyano‐4‐hydroxy‐cinnamate. These results suggest that lactate directly promotes the cell cycling rate and differentiation of OPCs, and that glycogen, one of the sources of lactate, contributes to remyelination in vivo. J. Cell. Physiol. 232: 986–995, 2017. © 2016 The Authors. Journal of Cellular Physiology Published by Wiley Periodicals, Inc.     

Effect of embryonic cell cycle of nuclear donor embryos on the efficiency of nuclear transfer in Japanese black cattle

In the present study, the development in vitro and in vivo of nuclear transfer (NT) embryos reconstructed with embryonic cells (blastomeres) at the 32- to 63-cell (sixth cell cycle) and 64- to 127-cell (seventh cell cycle) stages was investigated to determine the optimum range of embryonic cell cycles for yielding the highest number of identical calves in Japanese black cattle. Rates of development to the blastocyst stage (overall efficiency) were higher in the sixth cell-cycle stage (45%) than in the seventh cell-cycle stage (12%). After the transfer of the blastocysts reconstructed with blastomeres of the sixth and seventh cell cycle-stage embryos to recipient heifers, there were no differences in the pregnancy (14/35: 40% versus 3/13: 23%, respectively) or calving rates (11/39: 28% versus 3/13: 23%, respectively). These results indicate that the highest number of identical calves would be obtained by using sixth cell cycle (32- to 63-cell)-stage embryos as nuclear donors.     

Mutagenicities of quinoline and its derivatives.

Quinoline, recently reported to be carcinogenic in rats [12], was mutagenic to Salmonella typhimurium tester strains TA100 and TA98 in the presence of the metabolic activation system S-9 mix. 2-Chloroquinoline, a non-carcinogen [12], was non-mutagenic with or without S-9 mix. 8-Hydroxyquinoline, which is t known to be carcinogenic, was mutagenic with S-9 mix to both bacterial strains. The mutagenicities of 17 other quinoline derivatives that are not known to be carcinogenic were tested, and 12 of these compounds were mutagenic.     

Genome-wide identification of the rice calcium-dependent protein kinase and its closely related kinase gene families: comprehensive analysis of the CDPKs gene family in rice

In plants, calcium acts as a universal second messenger in various signal transduction pathways. The plant-specific calcium-dependent protein kinases (CDPKs) play important roles regulating downstream components of calcium signaling. We conducted a genome-wide analysis of rice CDPKs and identified 29 CDPK genes and eight closely related kinase genes, including five CDPK-related kinases (CRKs), one calcium and calmodulin-dependent protein kinase (CCaMK) and two phosphoenolpyruvate (PEP) carboxylase kinase-related kinases (PEPRKs). The mRNA splicing sites of the rice CDPKs, CRKs and PEPRKs (but not OsCCaMK) are highly conserved, suggesting that these kinases are derived from a common ancestor. RNA gel blot analyses revealed that the majority of rice CDPK genes exhibited tissue-specific expression. Expression of OsCPK9 was elevated in seedlings infected by rice blast, indicating that this gene plays an important role in signaling in response to rice blast treatment. Our genomic and bioinformatic analyses will provide an important foundation for further functional dissection of the rice CDPK gene family.     

Cell-Free Synthesis of a Putative Precursor of Polygalacturonase in Tomato Fruits

By using a monospecific anti-polygalacturonase-2 antibody, a54K-dalton polypeptide was detected in in vitro translationproducts by a wheat germ cell-free translation system programmedwith polyadenylated RNA from ripe tomato pericarp tissue. Thisputative precursor of polygalacturonase was about 9K daltonslarger in molecular weight than polygalacturonase-2. (Received December 12, 1983; Accepted May 17, 1984)     

Correction to: Comparison of the usability of an automatic sleep staging program via portable 1-channel electroencephalograph and manual sleep staging with traditional polysomnography

Sleep and Biological Rhythms -