Higher plant DNA is methylated at CG and CNG targets. In this study we have investigated the tobacco methylation system in tissue culture using the methylation inhibitors 5-azacytidine (5-azaC), dihydroxypropyladenine (DHPA) and ethionine (Ethi), and methylation-sensitive restriction endonucleases HpaII, MspI, HhaI, EcoRII, ScrFI, and Fnu4HI. Surprisingly, CAG/CTG sequences, contrary to CG doublets and CCG/CGG triplets, appeared to be refractory to the inhibitory effect of 5-azaC. Thus 5-azaC cannot be considered a general inhibitor of DNA methylation in tobacco cells. On the other hand, DHPA, the inhibitor of S-adenosylhomocysteine (SAH) hydrolase, and Ethi caused hypomethylation of both CAG/CTG and CCG/CGG triplets but not of the CG doublets. The sensitivity of triplet-specific methylation to the inhibition of SAH hydrolase suggests the possibility that plant-specific DNA methylation at CNG targets might be modulated by alterations of the SAH/S-Adenosylmethionine ratio in plant cells.

• MeSH
• adenin analogy a deriváty   farmakologie   MeSH
• adenosylhomocysteinasa MeSH
• azacytidin farmakologie   MeSH
• cytosin-specifické DNA-methylasy metabolismus   MeSH
• DNA rostlinná metabolismus   MeSH
• ethionin farmakologie   MeSH
• genom rostlinný MeSH
• hydrolasy antagonisté a inhibitory   MeSH
• jedovaté rostliny * MeSH
• kultivované buňky MeSH
• metylace účinky léků   MeSH
• restrikční endonukleasy typu II MeSH
• tabák genetika   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• 9-(2,3-dihydroxypropyl)adenine MeSH Prohlížeč
• adenin MeSH
• adenosylhomocysteinasa MeSH
• azacytidin MeSH
• cytosin-specifické DNA-methylasy MeSH
• DNA rostlinná MeSH
• ethionin MeSH
• hydrolasy MeSH
• restrikční endonukleasy typu II MeSH

Changes in chromatin structure of the HRS60 family of repetitive sequences in tobacco DNA were studied after hypomethylation induced with 5-azacytidine or DL-ethionine. The TaqI site in the HRS60 units lies in nucleosomal core regions and its cleavage is enhanced in the hypomethylated chromatin. In contrast, the cleavage of the Sau3AI site located in linker DNA does not depend on the level of methylation of DNA.

• MeSH
• azacytidin farmakologie   MeSH
• chromatin účinky léků   ultrastruktura   MeSH
• DNA chemie   MeSH
• ethionin farmakologie   MeSH
• jedovaté rostliny MeSH
• mapování chromozomů MeSH
• metylace MeSH
• mikrokoková nukleasa metabolismus   MeSH
• molekulární sekvence - údaje MeSH
• nukleozomy účinky léků   ultrastruktura   MeSH
• restrikční endonukleasy typu II MeSH
• sekvence nukleotidů MeSH
• tabák chemie   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• azacytidin MeSH
• chromatin MeSH
• DNA MeSH
• ethionin MeSH
• mikrokoková nukleasa MeSH
• nukleozomy MeSH
• restrikční endonukleasy typu II MeSH

Plant DNA is distinguished from the DNA of all other organisms by its high content of 5-methylcytosine (5mC). 5mC levels may amount to 30% of total cytosines, distributed between the sequences CG and CXG. The results presented here show that the methylation status of CXG sequences could be influenced by culturing tobacco tissues on subtoxic concentrations of ethionine. The hypomethylating effect of ethionine, evaluated as the capability of MspI or HpaII to cleave the DNA, proved to be rather specific for CCG and differed from that of 5-azacytidine which did not discriminate between CG and CXG sequences.

• MeSH
• azacytidin farmakologie   MeSH
• cytosinnukleotidy chemie   MeSH
• DNA chemie   účinky léků   MeSH
• ethionin farmakologie   MeSH
• genom MeSH
• guaninnukleotidy chemie   MeSH
• jedovaté rostliny * MeSH
• metylace účinky léků   MeSH
• repetitivní sekvence nukleových kyselin účinky léků   MeSH
• tabák účinky léků   genetika   MeSH
• Publikační typ
• časopisecké články MeSH
• srovnávací studie MeSH
• Názvy látek
• azacytidin MeSH
• cytosinnukleotidy MeSH
• DNA MeSH
• ethionin MeSH
• guaninnukleotidy MeSH

Drugs like L-ethionine, 1,10-phenanthroline and 3-(2-thienyl)-DL-alanine which arrest Saccharomyces cerevisiae cells in the G1 phase, were unable to arrest Candida albicans cells. However, C. albicans could be arrested in G1 after a prolonged stationary phase. As compared to normal cells, there was a selective reduction in the level of accumulation of valine and glutamate in G1-arrested cells, while the phospholipid polar head group ratio was not significantly altered. When G1-arrested C. albicans cells were again allowed to grow, the level of different phospholipids started increasing at about the time of bud emergence (2.5 h) whereas reduced levels of accumulated valine and glutamate recovered within 1 h. The recovery of phospholipids and amino acid transport are two distinct events during the progression of C. albicans cells from G1 to S phase.

• MeSH
• alanin analogy a deriváty   farmakologie   MeSH
• aminokyseliny metabolismus   MeSH
• biologický transport MeSH
• buněčný cyklus MeSH
• Candida albicans cytologie   účinky léků   metabolismus   MeSH
• druhová specificita MeSH
• ethionin farmakologie   MeSH
• fenantroliny farmakologie   MeSH
• fosfolipidy metabolismus   MeSH
• kinetika MeSH
• Saccharomyces cerevisiae cytologie   MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Názvy látek
• 1,10-phenanthroline MeSH Prohlížeč
• 3-(2-thienyl)alanine MeSH Prohlížeč
• alanin MeSH
• aminokyseliny MeSH
• ethionin MeSH
• fenantroliny MeSH
• fosfolipidy MeSH

The susceptibility of Bacillus subtilis to amino acid analogues was found to be markedly influenced by the carbon source used in the test media. Thialysine inhibited the bacterium with a greater number of carbon sources than the other two analogues tested. 5-Hydroxylysine was inhibitory with glycerol, lactose, D-xylose, L-arabinose and soluble starch while ethionine showed toxicity with lactose, D-xylose and L-arabinose. None of these analogues were toxic at the levels tested when D-galactose was used as carbon source. The bacterium was not susceptible to thialysine with glycerol, to 5-hydroxylysine with L-arabinose and to ethionine with lactose.

• MeSH
• arabinosa metabolismus   MeSH
• Bacillus subtilis účinky léků   metabolismus   MeSH
• cystein analogy a deriváty   farmakologie   MeSH
• ethionin farmakologie   MeSH
• glukosa metabolismus   MeSH
• glycerol metabolismus   MeSH
• hydroxylysin farmakologie   MeSH
• maltosa metabolismus   MeSH
• mannitol metabolismus   MeSH
• metabolismus sacharidů * MeSH
• Publikační typ
• časopisecké články MeSH
• srovnávací studie MeSH
• Názvy látek
• arabinosa MeSH
• cystein MeSH
• ethionin MeSH
• glukosa MeSH
• glycerol MeSH
• hydroxylysin MeSH
• maltosa MeSH
• mannitol MeSH
• S-2-aminoethyl cysteine MeSH Prohlížeč

• MeSH
• bakteriální proteiny biosyntéza   MeSH
• bakteriální RNA metabolismus   MeSH
• časové faktory MeSH
• chloramfenikol farmakologie   MeSH
• enzymová indukce účinky léků   MeSH
• Escherichia coli enzymologie   imunologie   metabolismus   MeSH
• ethionin farmakologie   MeSH
• galaktosidasy biosyntéza   MeSH
• izotopy uhlíku MeSH
• messenger RNA biosyntéza   MeSH
• methionin farmakologie   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• bakteriální proteiny MeSH
• bakteriální RNA MeSH
• chloramfenikol MeSH
• ethionin MeSH
• galaktosidasy MeSH
• izotopy uhlíku MeSH
• messenger RNA MeSH
• methionin MeSH

• MeSH
• bakteriální proteiny biosyntéza   MeSH
• enzymy farmakologie   MeSH
• Escherichia coli účinky léků   MeSH
• ethionin farmakologie   MeSH
• galaktosidasy biosyntéza   MeSH
• izotopy uhlíku MeSH
• kyselina aspartová metabolismus   MeSH
• leucin metabolismus   MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• bakteriální proteiny MeSH
• enzymy MeSH
• ethionin MeSH
• galaktosidasy MeSH
• izotopy uhlíku MeSH
• kyselina aspartová MeSH
• leucin MeSH

• Klíčová slova
• ETHIONINE/pharmacology *,
• MeSH
• biochemické jevy * MeSH
• ethionin farmakologie   MeSH
• Orthomyxoviridae * MeSH
• Publikační typ
• časopisecké články MeSH
• Názvy látek
• ethionin MeSH