title: Ethanol fermentation driven by elevated expression of the G1 cyclin gene CLN3 in sake yeast.
abstract: Cellular and subcellular morphology reflects the physiological state of a cell. To determine the physiological nature of sake yeast with superior fermentation properties, we quantitatively analyzed the morphology of sake yeast cells by using the CalMorph system. All the sake strains examined here exhibited common morphological traits that are typically observed in the well-characterized whiskey (whi) mutants that show accelerated G(1)/S transition. In agreement with this finding, the sake strain showed less efficient G(0)/G(1) arrest and elevated expression of the G(1) cyclin gene CLN3 throughout the fermentation period. Furthermore, deletion of CLN3 remarkably impaired the fermentation rate in both sake and laboratory strains. Disruption of the SWI6 gene, a transcriptional coactivator responsible for Cln3p-mediated G(1)/S transition, also resulted in a decreased fermentation rate, whereas whi mutants exhibited significant improvement in the fermentation rate, demonstrating positive roles of Cln3p and its downstream signalling pathway in facilitating ethanol fermentation. The combined results indicate that enhanced induction of CLN3 contributes to the high fermentation rate of sake yeast, which are natural whi mutants.
authors: National Research Institute of Brewing, 3-7-1 Kagamiyama, Higashi-hiroshima, Hiroshima 739-0046, Japan.
authors: Daisuke
authors: D
authors: Watanabe
authors: Satoru
authors: S
authors: Nogami
authors: Yoshikazu
authors: Y
authors: Ohya
authors: Yoichiro
authors: Y
authors: Kanno
authors: Yan
authors: Y
authors: Zhou
authors: Takeshi
authors: T
authors: Akao
authors: Hitoshi
authors: H
authors: Shimoi
mesh_terms: D000434:Alcoholic Beverages / Q000382:microbiology*; D056766:Cyclin G1 / Q000235:genetics* / Q000378:metabolism; D000431:Ethanol / Q000378:metabolism*; D005285:Fermentation; D012441:Saccharomyces cerevisiae / Q000235:genetics* / Q000378:metabolism*; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics* / Q000378:metabolism
chemical_list: D056766:Cyclin G1; D029701:Saccharomyces cerevisiae Proteins; D000431:Ethanol