Ethylene levels are regulated by a plant encoded 1-aminocyclopropane-1-carboxylic acid deaminase.
Control of the levels of the plant hormone ethylene is crucial in the regulation of many developmental processes and stress responses. Ethylene production can be controlled by altering endogenous levels of 1-aminocyclopropane-1-carboxylic acid (ACC), the immediate precursor to ethylene or by altering its conversion to ethylene. ACC is known to be irreversibly broken down by bacterial or fungal ACC deaminases (ACDs). Sequence analysis revealed two putative ACD genes encoded for in the genome of Arabidopsis thaliana (A. thaliana) and we detected ACD activity in plant extracts. Expression of one of these A. thaliana genes (AtACD1) in bacteria indicated that it had ACD activity. Moreover, transgenic plants harboring antisense constructs of the gene decreased ACD activity to 70% of wild-type (WT) levels, displayed an increased sensitivity to ACC and produced significantly more ethylene. Taken together, these results show that AtACD1 can act as a regulator of ACC levels in A. thaliana.
McDonnell
Lisa
L
Department of Biology, Queen's University, Kingston, Ontario, Canada K7L 3N6.
Plett
Jonathan M
JM
Andersson-Gunnerås
Sara
S
Kozela
Christopher
C
Dugardeyn
Jasper
J
Van Der Straeten
Dominique
D
Glick
Bernard R
BR
Sundberg
Björn
B
Regan
Sharon
S
D000595:Amino Acid Sequence; D000598:Amino Acids, Cyclic / Q000378:metabolism; D051017:Apoptosis Regulatory Proteins / Q000235:genetics / Q000378:metabolism; D017360:Arabidopsis / Q000201:enzymology* / Q000235:genetics; D029681:Arabidopsis Proteins / Q000235:genetics / Q000378:metabolism; D019755:Carbon-Carbon Lyases / Q000235:genetics / Q000378:metabolism*; D004926:Escherichia coli / Q000378:metabolism; D005030:Ethylenes / Q000096:biosynthesis*; D018506:Gene Expression Regulation, Plant; D008969:Molecular Sequence Data; D010105:Oxygenases / Q000235:genetics / Q000378:metabolism; D010937:Plant Growth Regulators / Q000378:metabolism*; D030821:Plants, Genetically Modified / Q000201:enzymology / Q000235:genetics; D032107:Populus / Q000201:enzymology / Q000235:genetics; D012680:Sensitivity and Specificity; D016415:Sequence Alignment
D000598:Amino Acids, Cyclic; D051017:Apoptosis Regulatory Proteins; D029681:Arabidopsis Proteins; D005030:Ethylenes; D010937:Plant Growth Regulators; C023863:1-aminocyclopropane-1-carboxylic acid; C036216:ethylene; C482919:ACD1 protein, Arabidopsis; D010105:Oxygenases; C033634:1-aminocyclopropane-1-carboxylate deaminase; D019755:Carbon-Carbon Lyases