title: Molecular and Functional Characterization of FLOWERING LOCUS T Homologs in Allium cepa.
abstract: Onion bulbing is an important agricultural trait affecting economic value and is regulated by flowering-related genes. FLOWERING LOCUS T (FT)-like gene function is crucial for the initiation of flowering in various plant species and also in asexual reproduction in tuber plants. By employing various computational analysis using RNA-Seq data, we identified eight FT-like genes (AcFT) encoding PEBP (phosphatidylethanolamine-binding protein) domains in Allium cepa. Sequence and phylogenetic analyses of FT-like proteins revealed six proteins that were identical to previously reported AcFT1-6 proteins, as well as one (AcFT7) with a highly conserved region shared with AcFT6 and another (comp106231) with low similarity to MFT protein, but containing a PEBP domain. Homology modelling of AcFT7 proteins showed similar structures and conservation of amino acids crucial for function in AtFT (Arabidopsis) and Hd3a (rice), with variation in the C-terminal region. Further, we analyzed AcFT expression patterns in different transitional stages, as well as under SD (short-day), LD (long-day), and drought treatment in two contrasting genotypic lines EM (early maturation, 36101) and LM (late maturation, 36122). The FT transcript levels were greatly affected by various environmental factors such as photoperiod, temperature and drought. Our results suggest that AcFT7 is a member of the FT-like genes in Allium cepa and may be involved in regulation of onion bulbing, similar to other FT genes. In addition, AcFT4 and AcFT7 could be involved in establishing the difference in timing of bulb maturity between the two contrasting onion lines.
authors.affiliation: Department of Horticulture, Sunchon National University, 255, Jungang-ro, Suncheon, Jeonam-do 57922, Korea. mrkumarbiotech@gmail.com.
authors.forename: Ranjith Kumar
authors.initials: RK
authors.lastname: Manoharan
authors.affiliation: Department of Horticulture, Sunchon National University, 255, Jungang-ro, Suncheon, Jeonam-do 57922, Korea. han-402@hanmail.net.
authors.forename: Jeong Suk Hyeon
authors.initials: JS
authors.lastname: Han
authors.affiliation: Department of Horticulture, Sunchon National University, 255, Jungang-ro, Suncheon, Jeonam-do 57922, Korea. vharshavardhanan@gmail.com.
authors.forename: Harshavardhanan
authors.initials: H
authors.lastname: Vijayakumar
authors.affiliation: Research Center for Applied Sciences, Academia Sinica, Nangang, Taipei 11529, Taiwan. boopathi@sinica.edu.tw.
authors.forename: Boopathi
authors.initials: B
authors.lastname: Subramani
authors.affiliation: Department of Horticulture, Sunchon National University, 255, Jungang-ro, Suncheon, Jeonam-do 57922, Korea. senkuttybio@gmail.com.
authors.forename: Senthil Kumar
authors.initials: SK
authors.lastname: Thamilarasan
authors.affiliation: Department of Horticulture, Sunchon National University, 255, Jungang-ro, Suncheon, Jeonam-do 57922, Korea. jipark@sunchon.ac.kr.|Research Center for Applied Sciences, Academia Sinica, Nangang, Taipei 11529, Taiwan. jipark@sunchon.ac.kr.
authors.forename: Jong-In
authors.initials: JI
authors.lastname: Park
authors.affiliation: Department of Horticulture, Sunchon National University, 255, Jungang-ro, Suncheon, Jeonam-do 57922, Korea. nis@sunchon.ac.kr.
authors.forename: Ill-Sup
authors.initials: IS
authors.lastname: Nou
mesh_terms: D019295:Computational Biology / Q000379:methods*; D055864:Droughts; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D019697:Onions / Q000737:chemistry / Q000235:genetics* / Q000254:growth & development; D017440:Photoperiod; D010802:Phylogeny; D010940:Plant Proteins / Q000737:chemistry* / Q000235:genetics* / Q000378:metabolism; D017434:Protein Structure, Tertiary; D018749:RNA, Plant / Q000032:analysis; D017423:Sequence Analysis, RNA / Q000379:methods*; D040681:Structural Homology, Protein
chemical_list: D010940:Plant Proteins; D018749:RNA, Plant
keywords: Allium cepa; FLOWERING LOCUS T; contrasting line; gene expression; modelling