Organelle asymmetry for proper fitness, function, and fate

Abstract

During cellular division, centrosomes are tasked with building the bipolar mitotic spindle, which partitions the cellular contents into two daughter cells. While every cell will receive an equal complement of chromosomes, not every organelle is symmetrically passaged to the two progeny in many cell types. In this review, we highlight the conservation of nonrandom centrosome segregation in asymmetrically dividing stem cells, and we discuss how the asymmetric function of centrosomes could mediate nonrandom segregation of organelles and mRNA. We propose that such a mechanism is critical for insuring proper cell fitness, function, and fate.

Metabolic requirements for the maintenance of self-renewing stem cells

“…During cell division, whereas every daughter cell receives an equal complement of chromosomes, not all organelles, including mitochondria, are symmetrically transmitted to the progeny in many cell types 140 . This was thought to be important for proper cell function and fate, especially during stem cell asymmetric division.…”

Amorphous no more: subdiffraction view of the pericentriolar material architecture

“…A systematic biochemical analysis of the interactions with recombinant material or sub-complexes purified from cell extracts at various stages of centrosome assembly will be necessary to answer these questions directly. Considering the importance of microtubule organization and anchoring in specialized cellular processes including stem cell division, it would be important to analyze the similarities and differences in the PCM organization during interphase in cells about to undergo symmetric vs asymmetric divisions(5,92). …”

RNA localization regulates diverse and dynamic cellular processes

“…Intriguingly, non‐membrane bound organelles, such as the centrosome, are another site of RNA localization. The centrosome is the major microtubule organizing center of most animal cells and directs the formation of the mitotic spindle in dividing cells . While the centrosome is often discussed as a proteinaceous organelle, there are longstanding hints that RNA may contribute to its biology (see Marshall and Rosenbaum and Alliegro).…”

“…RNA may regulate centrosome biology, such as assembly or biogenesis, through localized regulation of translation or through a structural role. In addition, the asymmetric distribution of RNAs at centrosomes may contribute to asymmetric cell division or cellular specializations . Future studies are required to test these hypotheses.…”