کد مقاله کد نشریه سال انتشار مقاله انگلیسی نسخه تمام متن
8407022 1544970 2015 17 صفحه PDF دانلود رایگان
عنوان انگلیسی مقاله ISI
Swinger RNAs with sharp switches between regular transcription and transcription systematically exchanging ribonucleotides: Case studies
موضوعات مرتبط
مهندسی و علوم پایه ریاضیات مدل‌سازی و شبیه سازی
پیش نمایش صفحه اول مقاله
Swinger RNAs with sharp switches between regular transcription and transcription systematically exchanging ribonucleotides: Case studies
چکیده انگلیسی
During RNA transcription, DNA nucleotides A,C,G, T are usually matched by ribonucleotides A, C, G and U. However occasionally, this rule does not apply: transcript-DNA homologies are detectable only assuming systematic exchanges between ribonucleotides. Nine symmetric (X↔Y, e.g. A↔C) and fourteen asymmetric (X↔Y↔Z, e.g. A↔C↔G) exchanges exist, called swinger transcriptions. Putatively, polymerases occasionally stabilize in unspecified swinger conformations, possibly similar to transient conformations causing punctual misinsertions. This predicts chimeric transcripts, part regular, part swinger-transformed, reflecting polymerases switching to swinger polymerization conformation(s). Four chimeric Genbank transcripts (three from human mitochondrion and one murine cytosolic) are described here: (a) the 5′ and 3′ extremities reflect regular polymerization, the intervening sequence exchanges systematically between ribonucleotides (swinger rule G↔U, transcript (1), with sharp switches between regular and swinger sequences; (b) the 5′ half is 'normal', the 3′ half systematically exchanges ribonucleotides (swinger rule C↔G, transcript (2), with an intercalated sequence lacking homology; (c) the 3′ extremity fits A↔G exchanges (10% of transcript length), the 5′ half follows regular transcription; the intervening region seems a mix of regular and A↔G transcriptions (transcript 3); (d) murine cytosolic transcript 4 switches to A↔U + C↔G, and is fused with A↔U + C↔G swinger transformed precursor rRNA. In (c), each concomitant transcript 5′ and 3′ extremities match opposite genome strands. Transcripts 3 and 4 combine transcript fusions with partial swinger transcriptions. Occasional (usually sharp) switches between regular and swinger transcriptions reveal greater coding potential than detected until now, suggest stable polymerase swinger conformations.
ناشر
Database: Elsevier - ScienceDirect (ساینس دایرکت)
Journal: Biosystems - Volume 135, September 2015, Pages 1-8
نویسندگان
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