A new structure in human cells, called reticular adhesions, has been discovered by researchers at Karolinska Institutet in collaboration with colleagues in the UK.
The structure is a new type of protein complex that the cell uses to attach to its surroundings and proves to play a key part in cell division.
“It’s incredibly surprising that there’s a new cell structure left to discover in 2018,” says principal investigator Staffan Strömblad, professor at the Department of Biosciences and Nutrition, Karolinska Institutet. “The existence of this type of adhesion complex has completely passed us by.”
Answers to yet unanswered questions
The newly discovered adhesion complex can provide answers to an as-yet unanswered question – how the cell can remain attached to the matrix during cell division. The previously known adhesion complexes dissolve during the process to allow the cell to divide. But not this new type.
“We’ve shown that this new adhesion complex remains and attaches the cell during cell division,” says Professor Strömblad.
The researchers also show that the newly discovered structures control the ability of daughter cells to occupy the right place after cell division. This memory function was interrupted when the researchers blocked the adhesion complex.
The study was done on human cell lines mainly using confocal microscopy and mass spectrometry. Further research is now needed to examine the new adhesion complex in living organisms.
“Our findings raise many new and important questions about the presence and function of these structures,” says Professor Strömblad. “We believe that they’re also involved in other processes than cell division, but this remains to be discovered.”
The researchers call the newly discovered cell structure ‘reticular adhesions’ to reflect their net-like form.
The study is published in the journal Nature Cell Biology.
Image showing: Three-dimensional projection of a cancer cell that has been rounded to undergo cell division and adheres to the substrate with reticular adhesions. Blue – Chromatin (DNA); Red – Cell’s outer shell (membrane); Green/Yellow in the bottom of the cell – Reticular adhesions. The image was created by John Lock, using a confocal microscope. Photographer: John Lock