Characterization of Arabidopsis GLN1;5 knockout mutant
2018
Authors:
Ćuković, KatarinaDragićević, Milan
Zdravković-Korać, Snežana
Simonović, Ana
Bogdanović, Milica
Todorović, Slađana
Contributors
Uzelac, BrankaDocument Type:
Conference object (Published version)
,
© 2018 by the Serbian Plant Physiology Society
Metadata
Show full item recordAbstract:
Glutamine synthetase is a key enzyme of plant nitrogen metabolism that assimilates ammonia
into glutamine. The Arabidopsis genome encodes one chloroplastic (GLN2) and five cytosolic
isoforms, GLN1;1 through GLN1;5, with different expression patterns, kinetic properties, regulation
and functions. Physiological roles of different isoforms have been elucidated mainly by studying
knockout mutants. However, the role of GLN1;5, which is expressed in dry seeds, remained unknown.
To elucidate the GLN1;5 function, we have studied a GLN1;5 knockout line (GLN1;5KO),
homozygous for T-DNA insertion within the GLN1;5. The GLN1;5 deficiency results in a phenotype
with slightly delayed bolting and fewer siliques. The dry weight of GLN1;5KO seeds is 73.3% of WT
seed weight, with seed length 90.9% of WT seeds. Finally, only 18.33% mutant seeds germinated
in water within 10 days, in comparison to 34.67% of WT seeds. KNO3 strongly stimulated germination
of both GLN1;5KO and WT seeds, while germination in increasing NH4Cl concentrations
potentiates the differences between the two genotypes. It can be concluded that GLN1;5 activity
supports silique development and grain filling and that it has a role in ammonium reassimilation
within the seed, as well as assimilation and/or detoxification of ammonium from the environment.
Keywords:
Arabidopsis; glutamine synthetase; knockout mutant; phenotype; germinationFunding / projects:
- Physiological, chemical and molecular analysis of the diversity of selected rare and endangered plant species and application of biotechnology for ex situ conservation and production of biologically active compounds (RS-MESTD-Basic Research (BR or ON)-173024)
In:
- Uzelac B, editor. Book of abstracts. 3rd International Conference on Plant Biology (22nd SPPS Meeting); 2018 Jun 9-12; Belgrade, Serbia. Belgrade: Serbian Plant Physiology Society; Institute for Biological Research "Siniša Stanković"; Faculty of Biology; 2018. p. 18.