RESUMO
Lead (Pb), a heavy metal, has become a crucial pollutant in soil and water, causing not only permanent and irreversible health problems, but also substantial reduction in crop yields. In this study, we conducted proteome analysis of the roots of the non-hyperaccumulator inbred maize line 9782 at four developmental stages (0, 12, 24, and 48 h) under Pb pollution using isobaric tags for relative and absolute quantification technology. A total of 252, 72 and 116 proteins were differentially expressed between M12 (after 12-h Pb treatment) and CK (water-mocked treatment), M24 (after 24-h Pb treatment) and CK, and M48 (after 48-h Pb treatment) and CK, respectively. In addition, 14 differentially expressed proteins were common within each comparison group. Moreover, Cluster of Orthologous Groups enrichment analysis revealed predominance of the proteins involved in posttranslational modification, protein turnover, and chaperones. Additionally, the changes in protein profiles showed a lower concordance with corresponding alterations in transcript levels, indicating important roles for transcriptional and posttranscriptional regulation in the response of maize roots to Pb pollution. Furthermore, enriched functional categories between the successive comparisons showed that the proteins in functional categories of stress, redox, signaling, and transport were highly up-regulated, while those in the functional categories of nucleotide metabolism, amino acid metabolism, RNA, and protein metabolism were down-regulated. This information will help in furthering our understanding of the detailed mechanisms of plant responses to heavy metal stress by combining protein and mRNA profiles.
Assuntos
Chumbo/toxicidade , Proteínas de Plantas/genética , Raízes de Plantas/efeitos dos fármacos , Proteoma/genética , Poluentes do Solo/toxicidade , Transcriptoma , Zea mays/efeitos dos fármacos , Aminoácidos/metabolismo , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Regulação da Expressão Gênica de Plantas , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismo , Anotação de Sequência Molecular , Oxirredução , Proteínas de Plantas/metabolismo , Raízes de Plantas/genética , Raízes de Plantas/crescimento & desenvolvimento , Raízes de Plantas/metabolismo , Proteoma/metabolismo , RNA de Plantas/genética , RNA de Plantas/metabolismo , Transdução de Sinais , Estresse Fisiológico , Zea mays/genética , Zea mays/crescimento & desenvolvimento , Zea mays/metabolismoRESUMO
The development of molecular markers has contributed to progress in identifying the gene(s) responsible for favorable variations in maize studies. In this study, quantitative trait locus (QTL) mapping was conducted using simple sequence repeat markers in an F2 sweet corn population from a cross between parental line 1132 and space flight-induced mutant line 751 to identify the loci contributing to an increase in some yield traits. A primary mutated genomic region was located on chromosome 9. In total, 26 QTL were detected for eight yield-related traits and assembled into three clusters on chromosome 9. The largest QTL cluster at bin 9.02/03, primarily contributing to >10% of the phenotypic variation in ear and cob diameters, was likely due to a major QTL. Desired alleles of these QTL were provided by the mutant line 751. The primary action of the major mutant allele was an additive effect. Another mutant locus, which was induced in bin 9.01, increased cob and ear diameters by dominant genetic action.