Accumulation of lead in the roots of grass pea (Lathyrus sativus L.) plants triggers systemic variation in gene expression in the shoots.
The impact of lead nitrate (Pb(NO(3))(2); 0.5mM) on steady-state accumulation of messengers corresponding to stress responsive genes was studied in two local lines of 11-d grass pea (Lathyrus sativus L.) plants exposed for 96 h in a hydroponic system. Real-time reverse transcription polymerase chain reaction technique was used with grass pea-specific primers designed from newly isolated partial cDNA. Increases in accumulation of glutathione reductase, ascorbate peroxidase and glutathione S-transferase transcripts suggested that roots enhanced detoxification mechanisms involving glutathione. In the leaves where no lead was translocated, the pollutant indirectly triggered increases in expression of several genes. This process probably resulted from systemic signals originating from the roots where lead accumulated in large amounts, approximately 150 mg Pbg(-1) dry weight. A preventive and/or adaptive role for the signal is assumed, since it concerned genes implicated in reactive oxygen species scavenging (ascorbate peroxidase), protein protection (heat shock protein 70) and proteolysis (cysteine and aspartic proteases).
Brunet
Judicaëlle
J
Ecophysiologie Moléculaire (IBIOS, UMR Bioemco 7618), Université Paris Est-Créteil, 61 avenue du Général de Gaulle, 94010 Créteil Cedex, France.
Varrault
Gilles
G
Zuily-Fodil
Yasmine
Y
Repellin
Anne
A
D000818:Animals; D018076:DNA, Complementary / Q000235:genetics; D004785:Environmental Pollutants / Q000378:metabolism / Q000633:toxicity; D018506:Gene Expression Regulation, Plant / Q000187:drug effects*; D006801:Humans; D027807:Lathyrus / Q000187:drug effects / Q000235:genetics* / Q000378:metabolism* / Q000502:physiology; D007854:Lead / Q000378:metabolism* / Q000633:toxicity*; D009566:Nitrates / Q000378:metabolism* / Q000633:toxicity*; D018517:Plant Roots / Q000378:metabolism*; D018520:Plant Shoots / Q000187:drug effects / Q000235:genetics*; D018749:RNA, Plant / Q000235:genetics; D013312:Stress, Physiological / Q000187:drug effects / Q000235:genetics; D014158:Transcription, Genetic
D018076:DNA, Complementary; D004785:Environmental Pollutants; D009566:Nitrates; D018749:RNA, Plant; D007854:Lead; C017461:lead nitrate