title: Genome-Wide Identification, Localization, and Expression Analysis of Proanthocyanidin-Associated Genes inBrassica.
abstract: Proanthocyanidins (PA) is a type of prominent flavonoid compound deposited in seed coats which controls the pigmentation in allBrassicaspecies. Annotation ofBrassica junceagenome survey sequences showed 72 PA genes; however, a functional description of these genes, especially how their interactions regulate seed pigmentation, remains elusive. In the present study, we designed 19 primer pairs to screen a bacterial artificial chromosome (BAC) library ofB. juncea. A total of 284 BAC clones were identified and sequenced. Alignment of the sequences confirmed that 55 genes were cloned, with everyArabidopsisPA gene having 2-7 homologs inB. juncea. BLAST analysis using the recently releasedB. rapaorB. napusgenome database identified 31 and 58 homologous genes, respectively. Mapping and phylogenetic analysis indicated that 30B. junceaPA genes are located in the A-genome chromosomes except A04, whereas the remaining 25 genes are mapped to the B-genome chromosomes except B05 and B07. RNA-seq data and Fragments Per Kilobase of a transcript per Million mapped reads (FPKM) analysis showed that most of the PA genes were expressed in the seed coat ofB. junceaandB. napus, and thatBjuTT3, BjuTT18, BjuANR, BjuTT4-2, BjuTT4-3, BjuTT19-1, andBjuTT19-3are transcriptionally regulated, and not expressed or downregulated in yellow-seeded testa. Importantly, our study facilitates in better understanding of the molecular mechanism underlyingBrassicaPA profiles and accumulation, as well as in further characterization of PA genes.
authors.affiliation: Oilseed Crops Institute, Hunan Agricultural UniversityChangsha, Hunan, China; College of Life Sciences, Resources and Environment Sciences, Yichun UniversityYichun, China.
authors.forename: Xianjun
authors.initials: X
authors.lastname: Liu
authors.affiliation: Oilseed Crops Institute, Hunan Agricultural University Changsha, Hunan, China.
authors.forename: Ying
authors.initials: Y
authors.lastname: Lu
authors.affiliation: School of Biology, Hunan University of Science and Technology Xiangtan, China.
authors.forename: Mingli
authors.initials: M
authors.lastname: Yan
authors.affiliation: Oilseed Crops Institute, Hunan Agricultural University Changsha, Hunan, China.
authors.forename: Donghong
authors.initials: D
authors.lastname: Sun
authors.affiliation: Oilseed Crops Institute, Hunan Agricultural University Changsha, Hunan, China.
authors.forename: Xuefang
authors.initials: X
authors.lastname: Hu
authors.affiliation: Oilseed Crops Institute, Hunan Agricultural University Changsha, Hunan, China.
authors.forename: Shuyan
authors.initials: S
authors.lastname: Liu
authors.affiliation: Oilseed Crops Institute, Hunan Agricultural University Changsha, Hunan, China.
authors.forename: Sheyuan
authors.initials: S
authors.lastname: Chen
authors.affiliation: Oilseed Crops Institute, Hunan Agricultural University Changsha, Hunan, China.
authors.forename: Chunyun
authors.initials: C
authors.lastname: Guan
authors.affiliation: Oilseed Crops Institute, Hunan Agricultural University Changsha, Hunan, China.
authors.forename: Zhongsong
authors.initials: Z
authors.lastname: Liu
keywords: BAC library; Brassica spp.; gene cloning; proanthocyanidin biosynthesis; seed color