Ibrahim, N., Hassan, A., Sharaf, O., Saad, M., Elkholy, S., Abu El-Heba, G. (2021). A Novel Medicago truncatule AKT1-null Mutant Impairs Potassium and Sodium Ions Uptake and Affects Root Nodulation. Egyptian Journal of Botany, 61(1), 303-318. doi: 10.21608/ejbo.2021.38709.1536
Nahed Ibrahim; Asmaa Hassan; Omaima Sharaf; Mohamed Saad; Shereen Elkholy; Ghada Abu El-Heba. "A Novel Medicago truncatule AKT1-null Mutant Impairs Potassium and Sodium Ions Uptake and Affects Root Nodulation". Egyptian Journal of Botany, 61, 1, 2021, 303-318. doi: 10.21608/ejbo.2021.38709.1536
Ibrahim, N., Hassan, A., Sharaf, O., Saad, M., Elkholy, S., Abu El-Heba, G. (2021). 'A Novel Medicago truncatule AKT1-null Mutant Impairs Potassium and Sodium Ions Uptake and Affects Root Nodulation', Egyptian Journal of Botany, 61(1), pp. 303-318. doi: 10.21608/ejbo.2021.38709.1536
Ibrahim, N., Hassan, A., Sharaf, O., Saad, M., Elkholy, S., Abu El-Heba, G. A Novel Medicago truncatule AKT1-null Mutant Impairs Potassium and Sodium Ions Uptake and Affects Root Nodulation. Egyptian Journal of Botany, 2021; 61(1): 303-318. doi: 10.21608/ejbo.2021.38709.1536
A Novel Medicago truncatule AKT1-null Mutant Impairs Potassium and Sodium Ions Uptake and Affects Root Nodulation
1Department of Microbial Molecular Biology, Agricultural Genetic Engineering Research Institute (AGERI), Agricultural Research Center (ARC), Giza, Egypt
2Department of Nucleic Acid and Protein Structure, Agricultural Genetic Engineering Research Institute (AGERI), Agricultural Research Center (ARC), Giza, Egypt
3Department of Agricultural Microbiology, National Research Centre, Dokki, Giza, Egypt
4Biology Department, Faculty of Science, Taibah University, Almadina Almonawara, Kingdom of Saudi Arabia
5Department of Nucleic Acid and Protein Structure, Agricultural Genetic Engineering Research Institute (AGERI), Agricultural Research Centre (ARC), Giza, Egypt
6Biology Department, College of Science and Humanities, Prince Sattam bin Abdulaziz University, 11942 Alkharj, KSA
7Department of Plant Molecular Biology, Agricultural Genetic Engineering Research Institute (AGERI), Agricultural Research Centre (ARC), Giza, Egypt
Abstract
REVERSE genetic approach was used to isolate and characterize Medicago truncatula containing “knockout” mutations in gene involved in nodulation process and in many other physiological processes. More than 60 Tnt1-Flanking sequence tags (FSTs) ranging from ~70bp to ~600bp were isolated, sequenced and submitted to Genebank referring for akt1 mutant characterization. The proper Tnt1-insertion was mapped in chromosome number 8 of Medicago truncatula genome. It was precisely identified upstream the base number 141 and downstream of the ATG start codon of Medicago truncatula potassium channel AKT1 gene (MtAKT1). MtAKT1 gene encodes inwardly rectifying potassium channel was isolated, sequenced, and submitted to Genebank with accession number MN649185.1 .M. truncatula akt1 mutant is achieving higher number of deformed root nodules and shorter root length compared to wild type. akt1 nodules exhibited reduced size occupied with un-differentiated cells and abnormalities in symbiotic nodule zones. Non-functional nitrogen fixation zone and compacted infection zone were observed as well. AKT1 null mutant exhibits attenuation in its ability to maintain the proper K+ and Na+ ions content in akt1 seedlings which is 2-3 fold less than wild type seedlings,. In contrast, akt1 seedlings showed three-fold increase in Ca++ ion concentration compared to wild type. In conclusion Medicago truncatula mutant, akt1 is Tnt1-retrotransposon mutant impaired in inwardly rectifying potassium channel AKT1. As the first reported AKT1 null mutant was isolated from legume plants, this mutant is displaying abnormalities in nitrogen fixation organ and affecting ions uptake.