Analysis of Signaling Pathways During Heavy Metal Toxicity: A Functional Genomics Perspective

Abstract

Abiotic stresses have major limiting factors for plant growth and crop productivity. Plants have different mechanisms to maintain the physiological concentrations of essential metal ions and to minimize exposure to non-essential heavy metals. Some mechanisms are ubiquitous because they are also required for general metal homeostasis, and they minimize the damage caused by high concentrations of heavy metals in plants by detoxifi cation, thereby conferring tolerance to heavy metal stress. Metals in the cell are addressed using a range of storage and detoxifi cation strategies, including metal transport, chelating, traffi cking, and sequestration into the vacuole. A large number of genes encoding MAPK pathway components have a major role in cell proliferation and hormone action as well as in stress signaling. Germin-like protein genes were developed by various stresses including metal stress. Functional genomics (integrating genome sequencing, transcriptomics, proteomics, metabolomics, ionomics, and phenomics) allows large-scale gene function analysis with high-throughput technology and incorporates interaction of gene products at cellular and organism level.

The Role of Heavy Metals in Plant Response to Biotic Stress

“…Plant resistance mechanisms to heavy metals and biotic stress factors such as pathogenic fungi, bacteria and invertebrates, including insects are well known. However, progress in the field of abiotic and biotic stress signal transduction pathways and research results concerning metal hyperaccumulating plants make this topic still very interesting [ 106 , 110 , 111 , 112 , 113 , 114 , 115 , 116 ].…”

Uma Defesa Pesada: a Hiperacumulação de Metais e as suas Consequências para o Ecossistema

“…Os metais que conseguem entrar nas raízes são maioritariamente acumulados em vacúolos, evitando que sejam tóxicos para a planta [9,25]. Adicionalmente, as plantas podem lidar com a concentração elevada de metais pesados através da produção de compostos antioxidantes [25,26].…”