RT Journal Article
SR Electronic
T1 Nuclear envelope reshaping around the vacuole determines the morphology of the ribosomal DNA
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 2021.06.23.449658
DO 10.1101/2021.06.23.449658
A1 Emiliano Matos-Perdomo
A1 Silvia Santana-Sosa
A1 Jessel Ayra-Plasencia
A1 Félix Machín
YR 2021
UL http://biorxiv.org/content/early/2021/06/24/2021.06.23.449658.abstract
AB The ribosomal DNA array (rDNA) of Saccharomyces cerevisiae has served as a model to address chromosome organization. In cells arrested before anaphase (mid-M), the rDNA acquires a highly structured chromosomal organization referred to as the rDNA loop, whose length can double the cell diameter. Previous works established that complexes such as condensin and cohesin are essential to attain this structure. Here, we report that the rDNA loop adopts distinct morphologies that arise as spatial adaptations to changes in the nuclear morphology triggered during the mid-M arrests. Interestingly, the formation of the rDNA loop results in the appearance of a space under the loop (SUL) which is devoid of any nuclear component yet colocalizes with the vacuole. We finally show that the formation and maintenance of the rDNA loop and the SUL require TORC1 and membrane synthesis. We propose that the rDNA-associated nuclear envelope (NE) reshapes into a loop to accommodate the vacuole, with the nucleus becoming bilobed.Competing Interest StatementThe authors have declared no competing interest.