Glutamine Synthetase in Rice

Regulation of synthesis of glutamine synthetase by adenylylated glutamine synthetase.

We have examined three mutants of Klebsiella aerogenes whose genetic lesions (glnB, glnD, and glnE) are in loci unlinked to the structural gene for glutamine sythetase (glnA) and in which the control of both the level and state of adenylylation of glutamine synthetase is altered. Each mutation alters a different component of the adenylylation system of glutamine synthetase [L-glutamate:ammonia ...

Evolution of glutamine synthetase in vertebrates: multiple glutamine synthetase genes expressed in rainbow trout (Oncorhynchus mykiss).

Glutamine synthetase (GSase) is a key enzyme in nitrogen metabolism and encoded by a single gene in mammals. Using PCR cloning techniques, including RT-PCR from total RNA and PCR from a cDNA library, we find evidence of four expressed GSase mRNAs for the tetraploid rainbow trout. For two of these mRNAs (Onmy-GS01, -GS02) we characterize the full-length coding regions, and for two others (Onmy-G...

Ammonia emission from rice leaves in relation to photorespiration and genotypic differences in glutamine synthetase activity.

BACKGROUND AND AIMS Rice (Oryza sativa) plants lose significant amounts of volatile NH(3) from their leaves, but it has not been shown that this is a consequence of photorespiration. Involvement of photorespiration in NH(3) emission and the role of glutamine synthetase (GS) on NH(3) recycling were investigated using two rice cultivars with different GS activities. METHODS NH(3) emission (AER)...

Metabolic compartmentation of vertebrate glutamine synthetase: putative mitochondrial targeting signal in avian liver glutamine synthetase.

The evolution of uricoteley as a mechanism for hepatic ammonia detoxication in vertebrates required targeting of glutamine synthetase (GS) to liver mitochondria in the sauropsid line of descent leading to the squamate reptiles and archosaurs. Previous studies have shown that in birds and crocodilians, sole survivors of the archosaurian line, hepatic GS is translated without a transient, N-termi...

Biochemical and molecular analysis of glutamine synthetase gene in brassica napus L.