During cell division, RNA content is distributed between daughter cells through the parallel process involving division of the cytoplasm after DNA is replicated and divided equally by mitosis. RNA is not replicated in the same manner as DNA. Instead, RNA molecules produced prior to division are shared by the two daughter cells, providing them with the necessary components to initiate their metabolic functions.
Distribution of RNA Content in Daughter Cells
During cell division, not only must the DNA be equally distributed between the daughter cells, but the cells must also receive necessary components to maintain themselves. While DNA replication is a well-understood process occurring during the S phase of the cell cycle, the distribution of RNA content is less straightforward. RNA is not duplicated in the same way as DNA; instead, RNA molecules are produced continuously and selectively based on the cell's needs at any given time. Therefore, RNA content is generally distributed in daughter cells through the division of cytoplasmic contents, with both daughter cells inheriting a share of RNA produced by the parent cell prior to division.
In eukaryotic cells, the synthesis of RNA occurs within the nucleus as well as in the cytoplasm, depending on the type of RNA. Messenger RNA (mRNA) is synthesized and processed in the nucleus before being exported to the cytoplasm where it serves as a template for protein synthesis. Transfer RNA (tRNA) and ribosomal RNA (rRNA), which are crucial for protein synthesis, are also generated in the nucleus and find their functional locations within the cell.
As the cell prepares to divide, these RNA molecules are present within the cytoplasm. When the cytoplasm is distributed between the two daughter cells in cytoplasmic division, or cytokinesis, the RNA molecules are split between them. Unlike DNA, the distribution of RNA is not exact, but both daughter cells generally receive the RNA necessary to begin their independent functioning. Over time, each daughter cell will produce its own RNA as demanded by its metabolic activities and gene expression profiles.