title: Proteomic and comparative genomic analysis reveals adaptability of Brassica napus to phosphorus-deficient stress.
abstract: Given low solubility and immobility in many soils of the world, phosphorus (P) may be the most widely studied macronutrient for plants. In an attempt to gain an insight into the adaptability of Brassica napus to P deficiency, proteome alterations of roots and leaves in two B. napus contrasting genotypes, P-efficient 'Eyou Changjia' and P-inefficient 'B104-2', under long-term low P stress and short-term P-free starvation conditions were investigated, and proteomic combined with comparative genomic analyses were conducted to interpret the interrelation of differential abundance protein species (DAPs) responding to P deficiency with quantitative trait loci (QTLs) for P deficiency tolerance. P-efficient 'Eyou Changjia' had higher dry weight and P content, and showed high tolerance to low P stress compared with P-inefficient 'B104-2'. A total of 146 DAPs were successfully identified by MALDI TOF/TOF MS, which were categorized into several groups including defense and stress response, carbohydrate and energy metabolism, signaling and regulation, amino acid and fatty acid metabolism, protein process, biogenesis and cellular component, and function unknown. 94 of 146 DAPs were mapped to a linkage map constructed by a B. napus population derived from a cross between the two genotypes, and 72 DAPs were located in the confidence intervals of QTLs for P efficiency related traits. We conclude that the identification of these DAPs and the co-location of DAPs with QTLs in the B. napus linkage genetic map provide us novel information in understanding the adaptability of B. napus to P deficiency, and helpful to isolate P-efficient genes in B. napus.
  
  
  CONCLUSIONS
  Low P seriously limits the production and quality of B. napus. Proteomics and genetic linkage map were widely used to study the adaptive strategies of B. napus response to P deficiency, proteomic combined with comparative genetic analysis to investigate the correlations between DAPs and QTLs are scarce. Thus, we herein investigated proteome alteration of the roots and leaves in two B. napus genotypes, with different P-deficient tolerances, in response to long-term low P stress and short-term P-free starvation by 2-DE. And comparative genomic was conducted to map the DAPs to the linkage map of B. napus by sequence alignment. The present study offers new insights into adaptability mechanism of B. napus to P deficiency and provides novel information in map-based cloning to isolate the genes in B. napus and scientific improvement of P-efficient in practice.
authors: National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China; Microelement Research Center, Huazhong Agricultural University, Wuhan 430070, China.
authors: Shuisen
authors: S
authors: Chen
authors: National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China; Microelement Research Center, Huazhong Agricultural University, Wuhan 430070, China.
authors: Guangda
authors: G
authors: Ding
authors: National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China; Microelement Research Center, Huazhong Agricultural University, Wuhan 430070, China.
authors: Zhenhua
authors: Z
authors: Wang
authors: Microelement Research Center, Huazhong Agricultural University, Wuhan 430070, China.
authors: Hongmei
authors: H
authors: Cai
authors: National Key Laboratory of Crop Genetic Improvement, Huazhong Agricultural University, Wuhan 430070, China; Microelement Research Center, Huazhong Agricultural University, Wuhan 430070, China. Electronic address: fangsenxu@mail.hzau.edu.cn.
authors: Fangsen
authors: F
authors: Xu
mesh_terms: D000222:Adaptation, Physiological; D029688:Brassica napus / Q000235:genetics / Q000378:metabolism*; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D040901:Proteomics; D040641:Quantitative Trait Loci / Q000502:physiology; D013312:Stress, Physiological / Q000502:physiology*
chemical_list: D010940:Plant Proteins
keywords: Brassica napus; Comparative genomic; Differential abundance of protein species; Phosphorus deficiency; Proteomics; Quantitative trait locus