title: Disruption of fumarylacetoacetate hydrolase causes spontaneous cell death under short-day conditions in Arabidopsis.
abstract: Fumarylacetoacetate hydrolase (FAH) hydrolyzes fumarylacetoacetate to fumarate and acetoacetate, the final step in the tyrosine (Tyr) degradation pathway that is essential to animals. Deficiency of FAH in animals results in an inborn lethal disorder. However, the role for the Tyr degradation pathway in plants remains to be elucidated. In this study, we isolated an Arabidopsis (Arabidopsis thaliana) short-day sensitive cell death1 (sscd1) mutant that displays a spontaneous cell death phenotype under short-day conditions. The SSCD1 gene was cloned via a map-based cloning approach and found to encode an Arabidopsis putative FAH. The spontaneous cell death phenotype of the sscd1 mutant was completely eliminated by further knockout of the gene encoding the putative homogentisate dioxygenase, which catalyzes homogentisate into maleylacetoacetate (the antepenultimate step) in the Tyr degradation pathway. Furthermore, treatment of Arabidopsis wild-type seedlings with succinylacetone, an abnormal metabolite caused by loss of FAH in the Tyr degradation pathway, mimicked the sscd1 cell death phenotype. These results demonstrate that disruption of FAH leads to cell death in Arabidopsis and suggest that the Tyr degradation pathway is essential for plant survival under short-day conditions.
authors.affiliation: Hunan Provincial Key Laboratory of Crop Germplasm Innovation and Utilization, Hunan Agricultural University, Changsha 410128, China.
authors.forename: Chengyun
authors.initials: C
authors.lastname: Han
authors.forename: Chunmei
authors.initials: C
authors.lastname: Ren
authors.forename: Tiantian
authors.initials: T
authors.lastname: Zhi
authors.forename: Zhou
authors.initials: Z
authors.lastname: Zhou
authors.forename: Yan
authors.initials: Y
authors.lastname: Liu
authors.forename: Feng
authors.initials: F
authors.lastname: Chen
authors.forename: Wen
authors.initials: W
authors.lastname: Peng
authors.forename: Daoxin
authors.initials: D
authors.lastname: Xie
mesh_terms: D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000166:cytology* / Q000187:drug effects / Q000235:genetics; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D001483:Base Sequence; D016923:Cell Death / Q000187:drug effects / Q000235:genetics; D003001:Cloning, Molecular; D006537:Heptanoates / Q000494:pharmacology; D050560:Homogentisate 1,2-Dioxygenase / Q000235:genetics / Q000378:metabolism; D006867:Hydrolases / Q000235:genetics* / Q000378:metabolism; D008969:Molecular Sequence Data; D009154:Mutation; D010641:Phenotype; D017440:Photoperiod; D030821:Plants, Genetically Modified; D036226:Seedlings / Q000187:drug effects; D014443:Tyrosine / Q000378:metabolism*
chemical_list: D029681:Arabidopsis Proteins; D006537:Heptanoates; D014443:Tyrosine; C020804:succinylacetone; D050560:Homogentisate 1,2-Dioxygenase; D006867:Hydrolases; C020156:fumarylacetoacetase