6 research outputs found
卵母細胞におけるSnurf-Snrpn刷り込み調節中枢転写産物の発現とマウス7C刷り込みドメインの刷り込み機構における役割
長崎大学学位論文 学位記番号:博(医歯薬)甲第21号 学位授与年月日:平成18年3月20
PROMoter uPstream Transcripts share characteristics with mRNAs and are produced upstream of all three major types of mammalian promoters
PROMoter uPstream Transcripts (PROMPTs) were identified as a new class of human RNAs, which are heterologous in length and produced only upstream of the promoters of active protein-coding genes. Here, we show that PROMPTs carry 3′-adenosine tails and 5′-cap structures. However, unlike mRNAs, PROMPTs are largely nuclear and rapidly turned over by the RNA exosome. PROMPT-transcribing DNA is occupied by RNA polymerase II (RNAPII) complexes with serine 2 phosphorylated C-terminal domains (CTDs), mimicking that of the associated genic region. Thus, the inefficient elongation capacity of PROMPT transcription cannot solely be assigned to poor CTD phosphorylation. Conditions that reduce gene transcription increase RNAPII occupancy of the upstream PROMPT region, suggesting that they reside in a common transcription compartment. Surprisingly, gene promoters that are actively transcribed by RNAPI or RNAPIII also produce PROMPTs that are targeted by the exosome. RNAPIII PROMPTs bear hallmarks of RNAPII promoter-associated RNAs, explaining the physical presence of RNAPII upstream of many RNAPIII-transcribed genes. We propose that RNAPII activity upstream gene promoters are wide-spread and integral to the act of gene transcription