Genetic remodeling and transcriptional remodeling of subtelomeric heterochromatin are different.
The structure, the extension, and the regulatory functions of telomeric and subtelomeric heterochromatin are not completely understood partly due to the difficulty of separating structural from functional features. We have previously observed that genetic alterations of telomeric heterochromatin components relieve transcriptional silencing. We have developed an analytical system allowing the separate determination of the effects of transcription and of genetic alterations on the subtelomeric structures. The uncoupled analysis, performed on the left extremity of chromosome III of Saccharomyces cerevisiae, consists of genetic dissections, induction of transcription of a resident gene, and chromatin analysis. The results allow (i) the determination of the precise localization and of the extension of heterochromatin (here from 0.9 to 2.6 kb from the innermost extremity of the C(1-3)A tract) and (ii) the definition of the transcription and of the genetically induced chromatin remodelings and of their marked differences, thus allowing (iii) specific analyses of the structural effects of the genetic modification of the heterochromatin components.
Venditti
Sabrina
S
Centro di Studio per gli Acidi Nucleici (CNR), Fondazione Istituto Pasteur, Fondazione Cenci Bolognetti, Universita' di Roma La Sapienza, P. le A. Moro 5, 00185, Roma, Italy. sabrina.venditti@uniroma1.it
Di Stefano
Glauco
G
D'Eletto
Manuela
M
Di Mauro
Ernesto
E
D019943:Amino Acid Substitution; D017931:DNA Primers; D005656:Fungal Proteins / Q000235:genetics; D020868:Gene Silencing; D006570:Heterochromatin / Q000235:genetics*; D006657:Histones / Q000235:genetics; D000072235:Mating Factor; D016296:Mutagenesis; D016297:Mutagenesis, Site-Directed; D009154:Mutation; D010455:Peptides / Q000235:genetics; D011994:Recombinant Proteins / Q000737:chemistry / Q000378:metabolism; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000254:growth & development; D038281:Silent Information Regulator Proteins, Saccharomyces cerevisiae; D016615:Telomere / Q000235:genetics*; D015534:Trans-Activators / Q000235:genetics; D014158:Transcription, Genetic
D017931:DNA Primers; D005656:Fungal Proteins; D006570:Heterochromatin; D006657:Histones; D010455:Peptides; D011994:Recombinant Proteins; C084121:SIR1 protein, S cerevisiae; D038281:Silent Information Regulator Proteins, Saccharomyces cerevisiae; D015534:Trans-Activators; D000072235:Mating Factor