title: Genomic structural variations contribute to trait improvement during whole-genome shuffling of yeast.
abstract: Whole-genome shuffling (WGS) is a powerful technology of improving the complex traits of many microorganisms. However, the molecular mechanisms underlying the altered phenotypes in isolates were less clarified. Isolates with significantly enhanced stress tolerance and ethanol titer under very-high-gravity conditions were obtained after WGS of the bioethanol Saccharomyces cerevisiae strain ZTW1. Karyotype analysis and RT-qPCR showed that chromosomal rearrangement occurred frequently in genome shuffling. Thus, the phenotypic effects of genomic structural variations were determined in this study. RNA-Seq and physiological analyses revealed the diverse transcription pattern and physiological status of the isolate S3-110 and ZTW1. Our observations suggest that the improved stress tolerance of S3-110 can be largely attributed to the copy number variations in large DNA regions, which would adjust the ploidy of yeast cells and expression levels of certain genes involved in stress response. Overall, this work not only constructed shuffled S. cerevisiae strains that have potential industrial applications but also provided novel insights into the molecular mechanisms of WGS and enhanced our knowledge on this useful breeding strategy.
authors.affiliation: Institute of Microbiology, College of Life Sciences, Zhejiang University, Hangzhou, 310058, Zhejiang Province, China.
authors.forename: Dao-Qiong
authors.initials: DQ
authors.lastname: Zheng
authors.forename: Jie
authors.initials: J
authors.lastname: Chen
authors.forename: Ke
authors.initials: K
authors.lastname: Zhang
authors.forename: Ke-Hui
authors.initials: KH
authors.lastname: Gao
authors.forename: Ou
authors.initials: O
authors.lastname: Li
authors.forename: Pin-Mei
authors.initials: PM
authors.lastname: Wang
authors.forename: Xiao-Yang
authors.initials: XY
authors.lastname: Zhang
authors.forename: Feng-Guang
authors.initials: FG
authors.lastname: Du
authors.forename: Pei-Yong
authors.initials: PY
authors.lastname: Sun
authors.forename: Ai-Min
authors.initials: AM
authors.lastname: Qu
authors.forename: Shuang
authors.initials: S
authors.lastname: Wu
authors.forename: Xue-Chang
authors.initials: XC
authors.lastname: Wu
mesh_terms: D032621:DNA Shuffling; D056914:Genomic Structural Variation; D007621:Karyotyping; D060847:Metabolic Engineering / Q000379:methods*; D060888:Real-Time Polymerase Chain Reaction; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism*