Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Pivot Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Target Concepts:
Gene/Protein
Disease
Symptom
Drug
Enzyme
Compound
Query: EC:4.1.1.17 (
ornithine decarboxylase
)
6,351
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
Inserts which carried the
CUP
gene from Saccharomyces cerevisiae or Mucor racemosus were used as hybridization probes to measure the methylation state and expression of the
CUP
gene from Mucor rouxii at different stages of growth. It was observed that the fungus contains a
CUP
multigene family. All the
CUP
genes were present in a hypermethylated DNA region in nongrowing and isodiametrically growing spores and were not transcribed at these stages. After germ tube emergence,
CUP
genes became demethylated and transcriptionally active. Development, demethylation, and transcription of
CUP
genes were blocked by the
ornithine decarboxylase
inhibitor 1,4-diaminobutanone. These results suggest that genes that are activated during development became demethylated in this fungus.
...
PMID:Developmental regulation of CUP gene expression through DNA methylation in Mucor spp. 172 31
Mucorales constitute a group of fungi that, because of their growth characteristics, have been used extensively in the study of cell differentiation, cell morphogenesis, and stimuli perception. We have studied the role of polyamine metabolism in the development of different Mucorales, with emphasis on Mucor and Phycomyces species. It has been observed that previous to each differentiative step, the cellular levels of the most regulated enzyme of the pathway,
ornithine decarboxylase
(
ODC
), and polyamines suffer a noticeable increase. Addition of diaminobutanone (DAB), a competitive inhibitor of
ODC
, blocks all the corresponding differentiative phenomena. In its presence, germinating spores fail to produce germ tubes and keep growing isodiametrically; mycelia do not sporulate but continue their vegetative growth, and yeast cells are unable to engage in a dimorphic transition without alterations in their growth rate. This differential effect of the
ODC
inhibitor in growth and development is apparently due to the location of
ODC
in at least two different cell compartments, one of which is impermeable to the drug. Inhibition of development is counteracted by putrescine and more noticeably by 5-azacytidine (5AC), a strong inhibitor of DNA methylation. Methylation levels of DNA are high in spores, and they become reduced after germination. Demethylation is inhibited by hydroxyurea, which blocks DNA replication, and by DAB. The effect of the latter is reversed by 5AC. These results suggest a relationship between polyamines and DNA methylation. Analysis of metallothioneine gene (
CUP
) behavior and expression during spore germination has confirmed this hypothesis.(ABSTRACT TRUNCATED AT 250 WORDS)
...
PMID:Polyamines, DNA methylation, and fungal differentiation. 808 Jun 26