KSN heterozygosity is associated with continuous flowering of Rosa rugosa Purple branch  

作　　者：Mengjuan Bai Jinyi Liu Chunguo Fan Yeqing Chen Hui Chen Jun Lu Jingjing Sun Guogui Ning Changquan Wang 

机构地区：[1]College of Horticulture,Nanjing Agricultural University,Nanjing 210095,China [2]College of Horticulture and Forestry Sciences,Huazhong Agricultural University,Wuhan 430070,China

出　　处：《Horticulture Research》2021年第1期305-315,共11页园艺研究（英文）

基　　金：the National Key R&D Program of China(2019YFD1000400);the NSFC(31972449)and the NSFC-XINJIANG joint foundation(U1803102),which provided grants to Changquan Wang;the NSFC(31801890),which provided a grant to Jinyi Liu;and the Postgraduate Research&Practice Innovation Program of Jiangsu Province,which provided a grant to Mengjuan Bai.

摘　　要：Rose(Rosa spp.)plants flower via two contrasting methods:once flowering(OF)and continuous flowering(CF).Purple branch is a rare continuously flowering variety of Rosa rugosa that is extensively cultivated in China.However,the genetic basis of its CF behavior is unknown.We demonstrated that Purple branch is heterozygous for the TFL1 homolog KSN.One KSN allele with a 9kb Copia insertion was found to be identical to that from continuously flowering Rosa chinensis Old blush.The other allele was found to be a functional wild-type allele.The overall expression of KSN was closely linked to the floral transition,and it was significantly repressed in continuously flowering Purple branch compared with OF Plena.The promoter region of the normal KSN allele was hypermethylated,and histone methylation at H3H4,H3K9,and H3K27 of the KSN gene locus was modified in continuously flowering Purple branch.Silencing of the DNA methyltransferase genes MET1 and CMT3 and the histone methyltransferase gene SUVR5 in Purple branch led to enhanced KSN expression,but silencing of the histone demethylase gene JMJ12 suppressed KSN expression.Therefore,the CF habit of Purple branch may be due to reduced expression of KSN caused by the halved dose and may be associated with epigenetic modifications together with retrotransposon insertions along the chromosome.Our study revealed a novel mechanism underlying the CF behavior of rose plants.

关 键 词：EXPRESSION branch continuously 

分 类 号：S685.12[农业科学—观赏园艺]