title: Genome-Wide Survey and Expression Profile Analysis of the Mitogen-Activated Protein Kinase (MAPK) Gene Family in Brassica rapa.
abstract: Mitogen-activated protein kinase (MAPK) cascades are fundamental signal transduction modules in plants, controlling cell division, development, hormone signaling, and biotic and abiotic stress responses. Although MAPKs have been investigated in several plant species, a comprehensive analysis of the MAPK gene family has hitherto not been performed in Brassica rapa. In this study, we identified 32 MAPKs in the B. rapa genome by conducting BLASTP and syntenic block analyses, and screening for the essential signature motif (TDY or TEY) of plant MAPK proteins. Of the 32 BraMAPK genes retrieved from the Brassica Database, 13 exhibited exon splicing errors, excessive splicing of the 5' sequence, excessive retention of the 5' sequence, and sequencing errors of the 3' end. Phylogenetic trees of the 32 corrected MAPKs from B. rapa and of MAPKs from other plants generated by the neighbor-joining and maximum likelihood methods suggested that BraMAPKs could be divided into four groups (groups A, B, C, and D). Gene number expansion was observed for BraMAPK genes in groups A and D, which may have been caused by the tandem duplication and genome triplication of the ancestral genome of the Brassica progenitor. Except for five members of the BraMAPK10 subfamily, the identified BraMAPKs were expressed in most of the tissues examined, including callus, root, stem, leaf, flower, and silique. Quantitative real-time PCR demonstrated that at least six and five BraMAPKs were induced or repressed by various abiotic stresses and hormone treatments, respectively, suggesting their potential roles in the abiotic stress response and various hormone signal transduction pathways in B. rapa. This study provides valuable insight into the putative physiological and biochemical functions of MAPK genes in B. rapa.
authors.affiliation: College of Agronomy and Biotechnology, Southwest University, Beibei, Chongqing 400715, PR China; Chongqing Rapeseed Engineering Research Center, Southwest University, Beibei, Chongqing 400715, PR China; Engineering Research Center of South Upland Agriculture, Ministry of Education, Southwest University, Beibei, Chongqing 400715, PR China.
authors.forename: Kun
authors.initials: K
authors.lastname: Lu
authors.affiliation: College of Agronomy and Biotechnology, Southwest University, Beibei, Chongqing 400715, PR China.
authors.forename: Wenjin
authors.initials: W
authors.lastname: Guo
authors.affiliation: College of Agronomy and Biotechnology, Southwest University, Beibei, Chongqing 400715, PR China; College of Life Sciences, Chongqing Normal University, Chongqing 401331, PR China.
authors.forename: Junxing
authors.initials: J
authors.lastname: Lu
authors.affiliation: College of Agronomy and Biotechnology, Southwest University, Beibei, Chongqing 400715, PR China.
authors.forename: Hao
authors.initials: H
authors.lastname: Yu
authors.affiliation: College of Agronomy and Biotechnology, Southwest University, Beibei, Chongqing 400715, PR China; Chongqing Rapeseed Engineering Research Center, Southwest University, Beibei, Chongqing 400715, PR China; Engineering Research Center of South Upland Agriculture, Ministry of Education, Southwest University, Beibei, Chongqing 400715, PR China.
authors.forename: Cunmin
authors.initials: C
authors.lastname: Qu
authors.affiliation: College of Agronomy and Biotechnology, Southwest University, Beibei, Chongqing 400715, PR China; Chongqing Rapeseed Engineering Research Center, Southwest University, Beibei, Chongqing 400715, PR China; Engineering Research Center of South Upland Agriculture, Ministry of Education, Southwest University, Beibei, Chongqing 400715, PR China.
authors.forename: Zhanglin
authors.initials: Z
authors.lastname: Tang
authors.affiliation: College of Agronomy and Biotechnology, Southwest University, Beibei, Chongqing 400715, PR China; Chongqing Rapeseed Engineering Research Center, Southwest University, Beibei, Chongqing 400715, PR China; Engineering Research Center of South Upland Agriculture, Ministry of Education, Southwest University, Beibei, Chongqing 400715, PR China.
authors.forename: Jiana
authors.initials: J
authors.lastname: Li
authors.affiliation: College of Agronomy and Biotechnology, Southwest University, Beibei, Chongqing 400715, PR China; Chongqing Rapeseed Engineering Research Center, Southwest University, Beibei, Chongqing 400715, PR China; Engineering Research Center of South Upland Agriculture, Ministry of Education, Southwest University, Beibei, Chongqing 400715, PR China.
authors.forename: Yourong
authors.initials: Y
authors.lastname: Chai
authors.affiliation: College of Agronomy and Biotechnology, Southwest University, Beibei, Chongqing 400715, PR China; Chongqing Rapeseed Engineering Research Center, Southwest University, Beibei, Chongqing 400715, PR China; Engineering Research Center of South Upland Agriculture, Ministry of Education, Southwest University, Beibei, Chongqing 400715, PR China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Liang
mesh_terms: D000595:Amino Acid Sequence; D001937:Brassica / Q000201:enzymology* / Q000235:genetics*; D032461:Chromosomes, Plant / Q000235:genetics; D003001:Cloning, Molecular; D020869:Gene Expression Profiling; D018745:Genome, Plant / Q000235:genetics; D023281:Genomics; D020928:Mitogen-Activated Protein Kinases / Q000737:chemistry / Q000235:genetics*; D058977:Molecular Sequence Annotation; D008969:Molecular Sequence Data; D009928:Organ Specificity; D010802:Phylogeny; D016415:Sequence Alignment
chemical_list: D020928:Mitogen-Activated Protein Kinases