ACS2, a Saccharomyces Cerevisiae Gene Encoding Acetyl-Coenzyme A Synthetase, Essential for Growth on Glucose

The mechanism and mode of inheritance of resistance to acetyl-coenzyme A carboxylase (ACCase)-inhibiting herbicides was investigated in a biotype of Lolium rigidum that has evolved resistance following selection with diclofop-methyl for 10 consecutive years. ACCase extracted from the resistant biotype is > 6.9 times more resistant to inhibition by diclofop than enzyme from a susceptible biotype. Similar or greater levels of resistance were found to other related herbicides. There is no difference in absorption or metabolism of diclofop-methyl or haloxyfop-methyl between the resistant and susceptible biotypes, hence differential absorption or metabolism of these herbicides does not contribute to resistance. F1 families from reciprocal crosses between the resistant biotype and a susceptible biotype respond similarly to the herbicide and are nearly as resistant as the resistant parent, indicating that the resistance trait is nuclearly located and has incomplete dominance over susceptibility. F2 families treated with 26 and 208 g ai ha-1 of haloxyfop-ethoxyethyl reveal only two phenotypes: resistant plants showing no injury and susceptible plants showing no growth. At both rates of haloxyfop-ethoxyethyl, the segregation of resistance to susceptibility follows a ratio of 3:1 (R:S) that fits the predicted ratio for a single nuclear gene with high dominance. From the F1 and F2 data, it is concluded that resistance to haloxyfop in this resistant biotype of L. rigidum is inherited as a single nuclear incompletely dominant gene coding for a resistant form of the target enzyme ACCase.

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Transient mRNA responses in chemostat cultures as a method of defining putative regulatory elements: Application to genes involved in Saccharomyces cerevisiae acetyl-coenzyme A metabolism

Yeast ◽

10.1002/(sici)1097-0061(19980915)14:12<1089::aid-yea312>3.0.co;2-k ◽

1998 ◽

Vol 14 (12) ◽

pp. 1089-1104 ◽

Cited By ~ 17

Author(s):

Marco A. Van Den Berg ◽

Patricia De Jong-Gubbels ◽

H. Yde Steensma

Keyword(s):

Saccharomyces Cerevisiae ◽

Coenzyme A ◽

Regulatory Elements ◽

Acetyl Coenzyme A ◽

Acetyl Coenzyme ◽

Chemostat Cultures

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Inhibition of Acetyl Coenzyme A Carboxylase Activity Restores Expression of the INO1 Gene in a snf1Mutant Strain of Saccharomyces cerevisiae

Molecular and Cellular Biology ◽

10.1128/mcb.21.17.5710-5722.2001 ◽

2001 ◽

Vol 21 (17) ◽

pp. 5710-5722 ◽

Cited By ~ 75

Author(s):

Margaret K. Shirra ◽

Jana Patton-Vogt ◽

Andreas Ulrich ◽

Oksana Liuta-Tehlivets ◽

Sepp D. Kohlwein ◽

...

Keyword(s):

Saccharomyces Cerevisiae ◽

Fatty Acid ◽

Fatty Acid Biosynthesis ◽

Coenzyme A ◽

Phospholipid Biosynthesis ◽

Acid Biosynthesis ◽

Acetyl Coenzyme A ◽

Acetyl Coenzyme ◽

Soraphen A ◽

Acetyl Coenzyme A Carboxylase

ABSTRACT Mutations in the Saccharomyces cerevisiae SNF1 gene affect a number of cellular processes, including the expression of genes involved in carbon source utilization and phospholipid biosynthesis. To identify targets of the Snf1 kinase that modulate expression of INO1, a gene required for an early, rate-limiting step in phospholipid biosynthesis, we performed a genetic selection for suppressors of the inositol auxotrophy ofsnf1Δ strains. We identified mutations inACC1 and FAS1, two genes important for fatty acid biosynthesis in yeast; ACC1 encodes acetyl coenzyme A carboxylase (Acc1), and FAS1 encodes the β subunit of fatty acid synthase. Acc1 was shown previously to be phosphorylated and inactivated by Snf1. Here we show thatsnf1Δ strains with increased Acc1 activity exhibit decreased INO1 transcription. Strains carrying theACC1 suppressor mutation have reduced Acc1 activity in vitro and in vivo, as revealed by enzymatic assays and increased sensitivity to the Acc1-specific inhibitor soraphen A. Moreover, a reduction in Acc1 activity, caused by addition of soraphen A, provision of exogenous fatty acid, or conditional expression ofACC1, suppresses the inositol auxotrophy ofsnf1Δ strains. Together, these findings indicate that the inositol auxotrophy of snf1Δ strains arises in part from elevated Acc1 activity and that a reduction in this activity restores INO1 expression in these strains. These results reveal a Snf1-dependent connection between fatty acid production and phospholipid biosynthesis, identify Acc1 as a Snf1 target important forINO1 transcription, and suggest models in which metabolites that are generated or utilized during fatty acid biosynthesis can significantly influence gene expression in yeast.

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