The ferritins are multimeric, iron-storage proteins involved in the regulation of free iron levels in the cells. Four different ferritin genes have been identified in Arabidopsis. AtFer1 transcript strongly accumulates upon treatment with excess iron, via a nitric oxide-mediated pathway: an Iron Dependent Regulatory Sequence (IDRS), responsible for repression of AtFer1 gene transcription under low iron supply, is the end-target of such signal transduction pathway. However other cis-elements, different from the IDRS, regulate the developmental expression of the AtFer1 isoform as the AtFer1 promoter is also activated in leaves during age-dependent senescence in a IDRS-independent manner. In order to investigate physiological relevance of Arabidopsis AtFer1 ferritin during senescence we isolated a mutant line KO in the AtFer1 gene. This AtFer1 KO line shows symptoms of accelerated senescence: the decrease of maximal photochemical efficiency and the degradation of chlorophyll and proteins are indeed accelerated with respect to the wild-type. Interestingly, the KO line shows no accelerated dark-induced senescence. These results, together with the evidence that AtFer1 promoter activation precedes any visible senescing symptoms, suggest that AtFer1 is one key gene in the regulation of the onset of age-dependent senescence program in Arabidopsis.
AtFer1 ferritin gene regulates senescence in Arabidopsis / D. Tarantino, C. Soave,I. Murgia. ((Intervento presentato al convegno 42nd Congress SIFV (FISV) tenutosi a Rimini, Italia nel 2003.
|Titolo:||AtFer1 ferritin gene regulates senescence in Arabidopsis|
TARANTINO, DELIA (Primo)
SOAVE, CARLO (Secondo)
MURGIA, IRENE (Ultimo)
|Data di pubblicazione:||ott-2003|
|Settore Scientifico Disciplinare:||Settore BIO/04 - Fisiologia Vegetale|
|Citazione:||AtFer1 ferritin gene regulates senescence in Arabidopsis / D. Tarantino, C. Soave,I. Murgia. ((Intervento presentato al convegno 42nd Congress SIFV (FISV) tenutosi a Rimini, Italia nel 2003.|
|Appare nelle tipologie:||14 - Intervento a convegno non pubblicato|