Transcriptional profiling of aluminum toxicity and tolerance responses in maize roots.
Aluminum (Al) toxicity is a major factor limiting crop yields on acid soils. There is considerable genotypic variation for Al tolerance in most common plant species. In maize (Zea mays), Al tolerance is a complex phenomenon involving multiple genes and physiological mechanisms yet uncharacterized. To begin elucidating the molecular basis of maize Al toxicity and tolerance, a detailed temporal analysis of root gene expression under Al stress was performed using microarrays with Al-tolerant and Al-sensitive genotypes. Al altered the expression of significantly more genes in the Al-sensitive genotype, presumably as a result of more severe Al toxicity. Nevertheless, several Al-regulated genes exhibited higher expression in the Al-tolerant genotype. Cell wall-related genes, as well as low phosphate-responsive genes, were found to be regulated by Al. In addition, the expression patterns of genes related to Al-activated citrate release indicated that in maize this mechanism is probably regulated by the expression level and/or function of the citrate transporter. This study is the first comprehensive survey of global transcriptional regulation under Al stress. The results described here will help to further our understanding of how mechanisms of Al toxicity and tolerance in maize are regulated at the transcriptional level.
Maron
Lyza G
LG
Robert W. Holley Center for Agriculture and Health, United States Department of Agriculture/Agricultural Research Service, Cornell University, Ithaca, NY 14853, USA.
Kirst
Matias
M
School of Forest Resources and Conservation, Plant Molecular and Cellular Biology Program, Genetics Institute, University of Florida, PO Box 110410, Gainesville, FL 32611, USA.
Mao
Chuanzao
C
Robert W. Holley Center for Agriculture and Health, United States Department of Agriculture/Agricultural Research Service, Cornell University, Ithaca, NY 14853, USA.|State Key Laboratory of Plant Physiology and Biochemistry, College of Life Sciences, Zhejiang University, Hangzhou 310058, China.
Milner
Matthew J
MJ
Robert W. Holley Center for Agriculture and Health, United States Department of Agriculture/Agricultural Research Service, Cornell University, Ithaca, NY 14853, USA.
Menossi
Marcelo
M
Laboratório de Genômica Funcional, Centro de Biologia Molecular e Engenharia Genética, Universidade Estadual de Campinas, Campinas, São Paulo 13083-970, Brazil.
Kochian
Leon V
LV
Robert W. Holley Center for Agriculture and Health, United States Department of Agriculture/Agricultural Research Service, Cornell University, Ithaca, NY 14853, USA.
D000535:Aluminum / Q000378:metabolism / Q000633:toxicity*; D002473:Cell Wall / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D005838:Genotype; D016014:Linear Models; D026901:Membrane Transport Proteins / Q000235:genetics; D020411:Oligonucleotide Array Sequence Analysis; D018384:Oxidative Stress / Q000235:genetics; D010940:Plant Proteins / Q000235:genetics* / Q000502:physiology; D018517:Plant Roots / Q000187:drug effects / Q000235:genetics / Q000378:metabolism; D016133:Polymerase Chain Reaction; D003313:Zea mays / Q000187:drug effects* / Q000235:genetics / Q000378:metabolism
D026901:Membrane Transport Proteins; D010940:Plant Proteins; D000535:Aluminum