title: DNA methylation pattern of Photoperiod-B1 is associated with photoperiod insensitivity in wheat (Triticum aestivum).
abstract: As one of the three key components of the 'Green Revolution', photoperiod insensitivity is vital for improved adaptation of wheat (Triticum aestivum) cultivars to a wider geographical range. Photoperiod-B1a (Ppd-B1a) is one of the major genes that confers photoperiod insensitivity in 'Green Revolution' varieties, and has made a significant contribution to wheat yield improvement. In this study, we investigated the mechanisms underlying the photoperiod insensitivity of Ppd-B1a alleles from an epigenetic perspective using a combination of bisulfite genomic sequencing, orthologous comparative analysis, association analysis, linkage analysis and gene expression analysis. Based on the study of a large collection of wheat germplasm, we report two methylation haplotypes of Ppd-B1 and demonstrate that the higher methylation haplotype (haplotype a) was associated with increased copy numbers and higher expression levels of the Ppd-B1 gene, earlier heading and photoperiod insensitivity. Furthermore, assessment of the distribution frequency of the different methylation haplotypes suggested that the methylation patterns have undergone selection during the wheat breeding process. Our study suggests that DNA methylation in the regulatory region of the Ppd-B1 alleles, which is closely related to copy number variation, plays a significant role in wheat breeding, to confer photoperiod insensitivity and better adaptation to a wider geographical range.
authors: National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.|State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, 271018, China.
authors: Han
authors: H
authors: Sun
authors: National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
authors: Zhiai
authors: Z
authors: Guo
authors: National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
authors: Lifeng
authors: L
authors: Gao
authors: National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
authors: Guangyao
authors: G
authors: Zhao
authors: National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
authors: Wenping
authors: W
authors: Zhang
authors: National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
authors: Ronghua
authors: R
authors: Zhou
authors: National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
authors: Yongzhen
authors: Y
authors: Wu
authors: Biotechnology Research Institute, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
authors: Haiyang
authors: H
authors: Wang
authors: State Key Laboratory of Crop Biology, College of Life Sciences, Shandong Agricultural University, Tai'an, 271018, China.
authors: Hailong
authors: H
authors: An
authors: National Key Facility for Crop Gene Resources and Genetic Improvement, Institute of Crop Science, Chinese Academy of Agricultural Sciences, Beijing, 100081, China.
authors: Jizeng
authors: J
authors: Jia
mesh_terms: D000483:Alleles; D001947:Breeding; D019175:DNA Methylation; D044127:Epigenesis, Genetic; D017353:Gene Deletion; D018506:Gene Expression Regulation, Plant / Q000502:physiology*; D006239:Haplotypes; D017440:Photoperiod; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism*; D014908:Triticum / Q000235:genetics / Q000378:metabolism*
chemical_list: D010940:Plant Proteins
keywords: DNA methylation; Photoperiod-B1; adaptation; association; copy number variation; photoperiod insensitivity; wheat (Triticum aestivum)