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Entry URI http://metadb.riken.jp/db/SciNetS_ria224i/cria224u4ria224u16133214i
Entry name Ferrario-Méry Sylvie et al. 2005 Dec. Planta 223(1):28-39.
Title Physiological characterisation of Arabidopsis mutants affected in the expression of the putative regulatory protein PII.
Authors Bouvet Mélanie|Ferrario-Méry Sylvie|Hodges Michael|Leleu Olivier|Meyer Christian|Savino Gil
Abstract The PII signal transducing protein is involved in carbon/nitrogen (C/N) sensing in bacteria and cyanobacteria. In higher plants the function of the PII homolog GLB1 is not known. GLB1 transcripts were found in all plant organs tested, while in Arabidopsis leaves GLB1 expression and PII protein levels were not significantly affected by either the day/night cycle or N-nutrition. Its putative regulatory role in plants has been studied by analysing Arabidopsis thaliana T-DNA insertion lines in the GLB1 gene. These PII mutants showed an 80% (PIIV1 mutant) and 100% (PIIS2 mutant) reduced AtGLB1 transcript level and no detectable PII protein. They did not display an altered growth or developmental phenotype when grown under non-limiting conditions suggesting that the PII protein does not play a crucial role in plants. However, in vitro grown PII mutants did show a higher sensitivity to nitrite (NO (2) (-) ) compared to the wild-type plants. This observation is reminiscent of the role of PII in the regulation of NO (2) (-) metabolism in cyanobacteria. Furthermore, when grown hydroponically, the PII mutants displayed a slight increase in carbohydrate (starch and sugars) levels in response to N starvation and a slight decrease in the levels of ammonium (NH (4) (+) ) and amino acids (mainly Gln) in response to NH (4) (+) resupply. Although the phenotypic changes are rather small in the mutant lines, these data support the hypothesis of a subtle involvement of the PII protein in the regulation of some steps of primary C and N metabolism.
Pubmed ID 16133214
Journal Planta
Volume 223
Issue 1
Pages 28-39
Publication date 2005 Dec
Num of phenotype gene 0