1 research outputs found
RNA Post-transcriptional Modifications of an Early-Stage Large-Subunit Ribosomal Intermediate
Protein
production by ribosomes is fundamental to life, and proper
assembly of the ribosome is required for protein production. The RNA,
which is post-transcriptionally modified, provides the platform for
ribosome assembly. Thus, a complete understanding of ribosome assembly
requires the determination of the RNA post-transcriptional modifications
in all of the ribosome assembly intermediates and on each pathway.
There are 26 RNA post-transcriptional modifications in 23S RNA of
the mature Escherichia coli (E. coli) large ribosomal subunit. The levels of these
modifications have been investigated extensively only for a small
number of large subunit intermediates and under a limited number of
cellular and environmental conditions. In this study, we determined
the level of incorporations of 2-methyl adenosine, 3-methyl pseudouridine,
5-hydroxycytosine, and seven pseudouridines in an early-stage E. coli large-subunit assembly intermediate with
a sedimentation coefficient of 27S. The 27S intermediate is one of
three large subunit intermediates accumulated in E.
coli cells lacking the DEAD-box RNA helicase DbpA
and expressing the helicase inactive R331A DbpA construct. The majority
of the investigated modifications are incorporated into the 27S large
subunit intermediate to similar levels to those in the mature 50S
large subunit, indicating that these early modifications or the enzymes
that incorporate them play important roles in the initial events of
large subunit ribosome assembly