A joint research group of Nagoya University and Kyoto University has announced that when the growth of larvae is delayed in Drosophila, a tissue called the imaginal disc of the wing will slow down the growth rate by actively performing "cell turnover", and the body will be slowed down. I discovered a mechanism for the growth of the organization to keep pace.
The "Minute mutant", which has a heterozygous mutation in the function deletion of the ribosomal protein gene, grows remarkably slowly in the larval stage, but mysteriously, a tissue of normal shape and size is finally formed. ..In this way, in multicellular organisms, even if individual growth delays may occur due to various internal and external disturbances, some robust mechanism that corrects the delays and realizes normal development. Exists.
In order to clarify this unknown mechanism, we analyzed the larval stage of the Minute mutant in detail. It turned out that many cells are dead, and the "cell replacement (turnover)" in which extra cells are born is being actively performed.It was also found that when this cell turnover mechanism is disrupted by a genetic method, wing vein pattern abnormalities and morphological abnormalities appear in adult wings.That is, it was considered that the cell turnover mechanism induces normal tissue formation by slowing the substantial growth rate of the tissue and keeping it in line with the growth rate of the individual.
On the other hand, "ribosome disease", which has been attracting attention as a human disease in recent years, is also caused by an abnormality in a ribosome-related gene like the Minute mutant.This result also suggests that the symptoms of ribosome disease may be caused by the disruption of the cell turnover mechanism, and it is expected that it will lead to the elucidation of the pathogenic mechanism of ribosome disease in the future.
Paper information:[PLOS Genetics] Epithelial cell-turnover ensures robust coordination of tissue growth in Drosophila ribosomal protein mutants
