Warning: file_get_contents(https://eutils.ncbi.nlm.nih.gov/entrez/eutils/elink.fcgi?dbfrom=pubmed&id=27597760
&cmd=llinks): Failed to open stream: HTTP request failed! HTTP/1.1 429 Too Many Requests
in C:\Inetpub\vhosts\kidney.de\httpdocs\pget.php on line 215
Visualization of single endogenous polysomes reveals the dynamics of translation
in live human cells
#MMPMID27597760
Pichon X
; Bastide A
; Safieddine A
; Chouaib R
; Samacoits A
; Basyuk E
; Peter M
; Mueller F
; Bertrand E
J Cell Biol
2016[Sep]; 214
(6
): 769-81
PMID27597760
show ga
Translation is an essential step in gene expression. In this study, we used an
improved SunTag system to label nascent proteins and image translation of single
messenger ribonucleoproteins (mRNPs) in human cells. Using a dedicated reporter
RNA, we observe that translation of single mRNPs stochastically turns on and off
while they diffuse through the cytoplasm. We further measure a ribosome density
of 1.3 per kilobase and an elongation rate of 13-18 amino acids per second.
Tagging the endogenous POLR2A gene revealed similar elongation rates and
ribosomal densities and that nearly all messenger RNAs (mRNAs) are engaged in
translation. Remarkably, tagging of the heavy chain of dynein 1 (DYNC1H1) shows
this mRNA accumulates in foci containing three to seven RNA molecules. These foci
are translation sites and thus represent specialized translation factories. We
also observe that DYNC1H1 polysomes are actively transported by motors, which may
deliver the mature protein at appropriate cellular locations. The SunTag should
be broadly applicable to study translational regulation in live single cells.
free
free
free
