Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0162871 (abdominal aortic aneurysm)
 8,664 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Conserved sequence features in Saccharomyces cerevisiae CEN DNA are confined to a region of approximately 120 bp. The highly conserved 8 bp at the left (PuTCACPuTG) constitute the left boundary of a functional CEN DNA as shown by the analysis of a series of Bal31 deletions. The right boundary of a functional CEN DNA lies within the conserved 25 bp at the right (TGT-T-TG--TTCCGAA-----AAA) or a few base pairs further outside of the 120-bp region. One mutant which just lacks the left conserved DNA element PuTCACPuTG can still assemble into a partially functional mitotic centromere and it assembles into a well functioning meiotic centromere. The sequences between the two conserved terminal DNA elements can be increased in length (+50%) or in GC content (from 6% to 12%) without measurable changes in mitotic and meiotic segregations of plasmids carrying such CEN mutations. The naturally occurring length and GC content of this centromere DNA sequence element is, therefore, not essential for centromere function. We discuss the possibility that it partly acts as a hinge region between two domains. Finally, we tested integrations of CEN DNA into the genome and found a toleration of wild-type CEN6 DNA when present 3' of the LYS2 gene.
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PMID:Role of conserved sequence elements in yeast centromere DNA. 299 49

High levels of transcription are associated with increased mutation rates in Saccharomyces cerevisiae, a phenomenon termed transcription-associated mutation (TAM). To obtain insight into the mechanism of TAM, we obtained LYS2 forward mutation spectra under low- versus high-transcription conditions in which LYS2 was expressed from either the low-level pLYS2 promoter or the strong pGAL1-10 promoter, respectively. Because of the large size of the LYS2 locus, forward mutations first were mapped to specific LYS2 subregions, and then those mutations that occurred within a defined 736-bp target region were sequenced. In the low-transcription strain base substitutions comprised the majority (64%) of mutations, whereas short insertion-deletion mutations predominated (56%) in the high-transcription strain. Most notably, deletions of 2 nucleotides (nt) comprised 21% of the mutations in the high-transcription strain, and these events occurred predominantly at 5'-(G/C)AAA-3' sites. No -2 events were present in the low-transcription spectrum, thus identifying 2-nt deletions as a unique mutational signature for TAM.
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PMID:Identification of a distinctive mutation spectrum associated with high levels of transcription in yeast. 1514 74