粟酒裂殖酵母核糖体蛋白RPL21表达不足引发细胞粘附

Disruption of ribosomal protein L21 in fission yeast leads to cell adhesion

摘要:

【目的】随机选择裂殖酵母核糖体蛋白RPL21作为研究对象，分析其表达不足对细胞的影响。【方法】通过同源臂交换的方法，敲除裂殖酵母基因组中RPL21蛋白的编码基因rpl21-1和rpl21-2，观察突变菌株rpl21-1Δ和rpl21-2Δ细胞内的核糖体合成情况以及细胞表型变化。【结果】突变菌株rpl21-1Δ和rpl21-2Δ细胞内总的rpl21 (rpl21-1+rpl21-2)表达水平与野生型菌株相比分别减少了66.5%和58.7%，合成的核糖体总量较野生型菌株分别下降了62.8%和50.4%。突变菌株在YEPD液体培养基中培养时发生细胞粘附现象，而基因回补的重组菌株rpl21-1Δ/RPL21-1和rpl21-2Δ/RPL21-2突变株细胞中粘附现象消失。【结论】核糖体蛋白损伤造成核糖体合成受阻，进而引发细胞生长过程中的粘附在粟酒裂殖酵母中是普遍存在的现象。

Abstract:

[Objective] To determine the function of ribosome in fission yeast, while ribosomal protein L21 expression were disrupted. [Methods] We deleted rpl21-1 or rpl21-2 in the genome of fission yeast, by exchanging homologous regions. Determination of the ribosome synthesis and observation of the physiological properties were performed in rpl21-1Δ cells and rpl21-2Δ cells cultured in YEPD medium. [Results] Total expressed RPL21 in the rpl21-1Δ cells and rpl21-2Δ cells, including RPL21-1 and RPL21-2, was reduced by 66.5% and 58.7%, with the synthetic ribosome relevant reduced 62.8% and 50.4%, compared with wild type cells. In YEPD medium, both of the rpl21-1Δ cells and rpl21-2Δ cells were flocculated. This flocculation was suppressed by heterogeneous expression of RPL21-1 in the rpl21-1Δ strain or RPL21-2 in the rpl21-2Δ strain. [Conclusion] We suggest that it may be a common feature that reduction of ribosome level could trigger flocculation by disruption of any ribosomal protein expression in fission yeast.