Aneuploidy and copy number breakpoints in the genome of lager yeasts mapped by microarray hybridisation
Aneuploidy and copy number breakpoints in the genome of lager yeasts mapped by microarray hybridisation
复制标题
DOI：
10.1007/s00294-004-0504-x
复制
发表时间：
2004-06-01
期刊：
影响因子：
2.5
通讯作者：
James, TC
中科院分区：
文献类型：
--
作者：
Bond, U;Neal, C;James, TC
采用竞争性比较基因组杂交（CCGH）和实时定量聚合酶链反应（qRT-PCR）技术，在单基因分辨率下检测了两种底发酵啤酒酵母菌CMBS-33和6701的酿酒酵母样基因拷贝数。利用酿酒葡萄球菌每条染色体的基因顺序，我们观察到酿酒葡萄球菌样基因在两个菌株中连续组的拷贝数相似。然而，拷贝数的离散变化发生在不同的位点，表明大酵母基因组的非整倍体性质。大多数发生拷贝数变化的位点在两个菌株中都是保守的。我们还在第XVI染色体上发现了酿酒酵母DNA的一个大片段，该片段未能与两种大酿酒菌株的基因组DNA杂交，这表明该区域可能在大酿酒酵母菌株中存在显著差异或缺失。此外，从基因组的这一区域检测到非常低水平的mRNA转录物。有趣的是，在发酵条件下，其他地方（如染色体III）观察到的基因拷贝数增加与基因表达增加没有特异性相关，这表明剂量补偿可能在这些菌株的基因表达控制中起作用。
Competitive comparative genome hybridisation (CCGH) to Saccharomyces cerevisiae DNA microarrays and quantitative real-time polymerase chain reaction (qRT-PCR) assays are used to examine the copy number of S. cerevisiae-like genes, at single gene resolution, of two bottom-fermenting lager yeast strains, CMBS-33 and 6701. Using the S. cerevisiae gene order for each chromosome, we observe that the copy number for contiguous groups of S. cerevisiae-like genes is similar in both strains. However, discrete changes in copy number occur at distinct loci, indicating the aneuploid nature of the lager yeast genomes. The majority of loci where copy number changes occur are conserved in both strains. We also identify a large segment of S. cerevisiae DNA on chromosome XVI that fails to hybridise to genomic DNA from both lager strains, suggesting that this region may have diverged significantly or is absent in the lager yeast strains. Furthermore, very low levels of mRNA transcripts are detected from this region of the genome. Interestingly, the increased gene copy number observed elsewhere (e.g. chromosome III) does not correlate specifically with increased gene expression under fermentation conditions, suggesting that dosage compensation may play a role in controlling gene expression in these strains.