title: Molecular cloning, subcellular localization and characterization of two adenylate kinases from cassava, Manihot esculenta Crantz cv. KU50.
abstract: Adenylate kinase (ADK) is a phosphotransferase that plays an important role in cellular energy homeostasis. Many isozymes located in different subcellular compartments have been reported. In this study, we focus on the characterization of cassava (Manihot esculenta) ADKs. We found 15 ADKs that are publicly available in the African cassava genome database. We cloned two ADKs, namely MeADK1 and MeADK2, which are phylogenetically grouped together with the plastidial ADK in potato. Both MeADK1 and MeADK2 showed 66% identity in the amino acid sequences with plastidial ADK in potato. However, we demonstrated that they are localized to mitochondria using GFP fusions of MeADK1 and MeADK2. The Escherichia coli-produced recombinant MeADK1 and MeADK2 preferred forward reactions that produce ATP. They exhibited similar specific activities. The semi-quantitative RT-PCR analysis showed that MeADK1 and MeADK2 in 2-month-old leaves have similar expression patterns under a diurnal light-dark cycle. However, MeADK2 transcripts were expressed at much higher levels than MeADK1 in 5-month-old leaves and roots. Thus, we conclude that MeADK2 might play a vital role in energy homeostasis in cassava mitochondria.
authors: Department of Biochemistry, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Pathumwan, Bangkok 10330, Thailand.
authors: Channarong
authors: C
authors: Boonrueng
authors: Department of Biochemistry, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Pathumwan, Bangkok 10330, Thailand.
authors: Surachat
authors: S
authors: Tangpranomkorn
authors: Department of Biochemistry, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Pathumwan, Bangkok 10330, Thailand.
authors: Uthaman
authors: U
authors: Yazhisai
authors: Department of Biochemistry, Faculty of Science, Chulalongkorn University, 254 Phayathai Road, Pathumwan, Bangkok 10330, Thailand; Omics Sciences and Bioinformatics Center, Chulalongkorn University, 254 Phayathai Road, Pathumwan, Bangkok 10330, Thailand. Electronic address: supaart.s@chula.ac.th.
authors: Supaart
authors: S
authors: Sirikantaramas
mesh_terms: D000263:Adenylate Kinase / Q000235:genetics*; D003001:Cloning, Molecular; D003198:Computer Simulation; D005453:Fluorescence; D018506:Gene Expression Regulation, Plant; D002365:Manihot / Q000201:enzymology* / Q000235:genetics*; D010802:Phylogeny; D060888:Real-Time Polymerase Chain Reaction; D011994:Recombinant Proteins / Q000302:isolation & purification; D013347:Subcellular Fractions / Q000201:enzymology
chemical_list: D011994:Recombinant Proteins; D000263:Adenylate Kinase
keywords: Adenylate kinase; Cassava; Molecular cloning; Subcellular localization