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Functional Crypto-Adenylate Cyclases Operate in Complex Plant Proteins
Inas Al-Younis1, Basem Moosa2, Mateusz Kwiatkowski3
1Biological and Environmental Sciences and Engineering Division, King Abdullah University of Science and Technology, Thuwal, Saudi Arabia.
Frontiers in Plant Science
|August 30, 2021
Summary
Researchers identified novel plant adenylate cyclases (ACs) with low activity, termed crypto-ACs. These crypto-ACs may link cyclic AMP (cAMP) signaling to abscisic acid (ABA) synthesis in Arabidopsis thaliana.
Area of Science:
- Plant molecular biology
- Biochemistry
- Plant hormone signaling
Background:
- Adenylyl cyclases (ACs) and cyclic AMP (cAMP) are crucial regulators in plant responses.
- The specific roles of many ACs, especially those with low catalytic activity, remain largely uncharacterized in plants.
Purpose of the Study:
- To identify novel adenylate cyclases in Arabidopsis thaliana using sequence homology.
- To investigate the function of a specific candidate AC, NCED3, in abscisic acid (ABA) biosynthesis.
- To characterize the activity and potential role of low-activity ACs in plant regulatory mechanisms.
Main Methods:
- Bioinformatic screening using an amino acid search motif for annotated ACs.
- Sequence and structural analysis of candidate ACs, including NCED3 (At3g14440).
- Experimental validation of enzymatic activity using biochemical assays.
Main Results:
- Identified 12 unique candidate ACs in Arabidopsis thaliana.
- Four identified ACs play a role in abscisic acid (ABA) biosynthesis.
- NCED3 exhibits low but reproducible in vitro adenylate cyclase activity, designated as crypto-AC.
- Results support the hypothesis of low-activity ACs functioning within multi-domain moonlighting proteins.
Conclusions:
- Crypto-ACs represent a class of regulatory ACs with inherently low enzymatic activity.
- These crypto-ACs are likely integrated into multi-domain proteins with other functions.
- Potential role of crypto-ACs in linking cAMP signaling pathways to abscisic acid (ABA) synthesis in plants.
Keywords:
3',5'-cyclic adenosine monophosphate9-cis-epoxycarotenoid 11,12 dioxygenaseArabidopsis thalianaadenylyl cyclasecatalytic centercrypto-enzymesmulti-domain moonlighting enzymesMore Related Videos
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