This most basic life detail has only been unveiled-25 milliseconds through the nuclear hole

All proteins in cells are assembled by complex molecular machines
.

The precursors of these ribosomes are produced in the nucleus and then enter the cell through the so-called nuclear pore

The nucleus is a kind of vault: it is located inside the cell and protects the DNA, which contains the instructions for building all cellular proteins
.

When a cell needs a protein to complete a specific task, it orders a transcript that matches the DNA fragment in the nucleus

This means that most cell molecules are produced outside the nucleus
.

However, this does not apply to the ribosomes themselves: many of their components are already assembled in large numbers in the nucleus

The teams at the University of Bonn and ETH Zurich have now photographed the nuclear release of the larger 60S precursor subunit
.

Professor Ulrich Kubitscheck from the Institute of Physics and Theoretical Chemistry at the University of Bonn explained: “To do this, we stain the nuclear pores with a green dye and a red precursor 60S
.

” The recording itself was done with the help of a special microscope.
, The researchers also specially modified this microscope for this purpose

Gel plugging agent

"In this way, we have successfully captured the passage of individual ribosomal components through pores in real time for the first time in the world," said Dr.
Jan Ruland, the lead author of the study, who completed his PhD in the Kubitscheck research group
.

This is definitely not a trivial matter: the nucleus of human cells is actually covered with thousands of small holes
.

Each of them is only about one ten-thousandth of a millimeter in diameter

Transport through pores is a complex process: they are sealed by a gel that normally prevents the passage of large molecules
.

The subunits of ribosomes are huge; without assistance, they cannot leave the nucleus

It only takes 25 milliseconds to pass

This step seems to be the "bottleneck" of the transportation process
.

Siebrase said: "We were able to prove that the precursor 60S subunits were deposited right where the protein grabber penetrates into the pores

But the evaluation of the video also shows that export is not always effective
.

Only in the third case, a precursor 60S subunit touches a hole before it actually leaves the nucleus

This research provides more detailed insights into the formation of ribosomes
.
In addition, this method is also suitable for the study of other transport processes
.
"We have exhausted the current technological possibilities," Kubitscheck said
.
"The reviewers call our research for reference, and we hope that other groups can benefit from it.
This is not unreasonable
.
"

Original search: https:// reading: How many rings are there in the human nuclear pore complex in "Nature"?