Транскрипционный цикл у эукариот Л1-2014 - 11 февраля
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Figure 1. Distribution of NADs along human chromosomes in HeLa cells. Nucleolar organizer regions are indicated with light red boxes. Confocal microscopy images on the right illustrate frequent association of centromeres with nucleoli (Németh et al.,
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Сближение промотора и терминатора облегчает ре-инициацию транскрипции
В формировании петель участвуют TTF-1, SL1, c-Myc
PD Dr. Attila Németh Phone: +49 (941) 943 2846 attila.nemeth@ur.de
Regulation of ribosomal RNA synthesis and processing
Regulation of ribosomal gene transcription is a key factor in controlling cell growth. Our main interest lies on the understanding of the mechanisms that regulate transcription of ribosomal RNA genes and the tightly linked processing of the pre-rRNA.
We aim to answer the following questions in our ongoing projects:
•What are the cis and trans factors that regulate higher-ordered organization of rRNA genes on active and inactive nucleolar organizer regions?
•How are the active rRNA genes spatially organized within the mammalian nucleolus?
Figure 2. Loop model of rRNA gene transcription. TTF-I binds next to the spacer promoter (SP) and the gene promoter (P) of ribosomal DNA (rDNA) and to multiple binding sites in the terminator region. Promoter-terminator interactions are mediated by TTF-I suggesting looping of active genes (Németh et al., 2008, Diermeier et al., 2014).
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Терминация транскрипции
Механизм терминации «torpedo – Rat1»
Rnt1 – ядерная специфическая рибонуклеаза
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Регуляция транскрипции Pol I
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РНК полимераза III типы промоторов
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Промоторы РНК полимеразы III
и процессинг транскриптов
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