Differences in the way a mammalian cell and yeast cells coordinate cell growth and cell-cycle progression.
Differences in the way a mammalian cell and yeast cells coordinate cell growth and cell-cycle progression.
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哺乳动物细胞和酵母细胞协调细胞生长和细胞周期进展的方式的差异。
DOI：
10.1186/1475-4924-2-7
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发表时间：
2003
影响因子：
--
通讯作者：
Raff, Martin
中科院分区：
文献类型：
--
作者：
Conlon, Ian;Raff, Martin
人们普遍认为，细胞大小检查点有助于协调细胞生长和细胞周期进程，从而使增殖的真核细胞保持其大小。有强有力的证据表明酵母中存在这样的大小检查点，它们在增殖时保持恒定的细胞大小分布，即使大的酵母细胞比小的酵母细胞生长得更快。此外，当酵母细胞转移到更好或更差的营养条件下时，它们会在一个细胞周期内改变其大小阈值。哺乳动物细胞群体在增殖时也可以保持恒定的大小分布，但不知道这是否取决于细胞大小检查点。我们发现，增殖的大鼠雪旺细胞不需要细胞大小检查点来维持恒定的细胞大小分布，因为与酵母不同，大小雪旺细胞以相同的速率生长，这取决于细胞外生长因子的浓度。此外，当从无血清培养基转移到含血清培养基时，许旺细胞进行多次分裂以将其大小增加到适合新条件的大小，这表明它们没有与酵母中类似的细胞大小检查点。体外培养的雪旺细胞和酵母细胞似乎使用不同的机制来协调它们的生长与细胞周期进程。虽然酵母细胞使用细胞大小检查点，但施万细胞显然没有。在这方面，许多哺乳动物细胞很可能类似于许旺细胞。
It is widely believed that cell-size checkpoints help to coordinate cell growth and cell-cycle progression, so that proliferating eukaryotic cells maintain their size. There is strong evidence for such size checkpoints in yeasts, which maintain a constant cell-size distribution as they proliferate, even though large yeast cells grow faster than small yeast cells. Moreover, when yeast cells are shifted to better or worse nutrient conditions, they alter their size threshold within one cell cycle. Populations of mammalian cells can also maintain a constant size distribution as they proliferate, but it is not known whether this depends on cell-size checkpoints. We show that proliferating rat Schwann cells do not require a cell-size checkpoint to maintain a constant cell-size distribution, as, unlike yeasts, large and small Schwann cells grow at the same rate, which depends on the concentration of extracellular growth factors. In addition, when shifted from serum-free to serum-containing medium, Schwann cells take many divisions to increase their size to that appropriate to the new condition, suggesting that they do not have cell-size checkpoints similar to those in yeasts. Proliferating Schwann cells and yeast cells seem to use different mechanisms to coordinate their growth with cell-cycle progression. Whereas yeast cells use cell-size checkpoints, Schwann cells apparently do not. It seems likely that many mammalian cells resemble Schwann cells in this respect.