Palindromi i potencijalne sekundarne strukture u transkriptima izoformi biljnih glutamin-sintetaza
Palindromes and potential secondary structures in transcripts of plant glutamine synthetase isoforms
2016
Document Type:
Conference object (Published version)
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© 2015 Prirodno-matematički fakultet
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Show full item recordAbstract:
Glutamine synthetase (GS, E.C. 6.3.1.2) plays a central role in nitrogen metabolism by
assimilating ammonia into glutamine. Plants have one chloroplastic (GS2) and one or more cytosolic
(GS1) isoforms. Zea mays and Arabidopsis thaliana are among species with largest GS gene families,
having one GS2 and five GS1 genes. Regulation of expression of GS genes, as well as regulation of GS
enzymes at the posttranslational level has been widely studied. However, there is limited information on
the possibilities of posttranscriptional regulation at the level of GS transcripts. Hereby we show that
maize GS mRNAs may adopt stabile secondary structures in the form of hairpins and homo- or
heterodimers in the region preceding or including their AUG codon, which may influence translation
efficiency and transcript stability. The possibility of forming hairpins is based on the presence of
palindromes with gaps, while dimers can form if sequences contain palindromes without gaps. All six
maize GS transcripts, as well as three Arabidopsis GS transcripts have one 6-nt palindrome without gap,
while one Arabidopsis transcript has two gapless 6-nt palindromes. In addition, maize GS1-3 and
Arabidopsis GLN1;2 isoforms contain a perfect 8-nt palindrome with a gap. To show statistical
significance of these findings, the number of found palindromes in GS transcripts was expressed as a
ratio of found and expected number of palindromes of all sizes, with and without gaps in sequences of a
given length. Our bioinformatics analysis suggests that GS transcripts contain structural features that
allow regulation at the level of mRNAs, and presents a good starting point for experimental studies of the
proposed posttranslational regulation.
Keywords:
glutamine synthetase; posttranscriptional regulation; RNA secondary structures; palindromesFunding / 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:
- Kukavica Jovanović B, editor. III simpozijum biologa i ekologa Republike Srpske (SBERS, 2015): Zbornik radova; 2015 Nov 12-14; Banja Luka, Republika Srpska. Banja Luka: Prirodno-matematički fakultet; 2015. p. 29-40. (Skup; Vol. 7; No. 2).