title: Modifications to a LATE MERISTEM IDENTITY1 gene are responsible for the major leaf shapes of Upland cotton (Gossypium hirsutum L.).
abstract: Leaf shape varies spectacularly among plants. Leaves are the primary source of photoassimilate in crop plants, and understanding the genetic basis of variation in leaf morphology is critical to improving agricultural productivity. Leaf shape played a unique role in cotton improvement, as breeders have selected for entire and lobed leaf morphs resulting from a single locus, okra (l-D1), which is responsible for the major leaf shapes in cotton. The l-D1locus is not only of agricultural importance in cotton, but through pioneering chimeric and morphometric studies, it has contributed to fundamental knowledge about leaf development. Here we show that an HD-Zip transcription factor homologous to the LATE MERISTEM IDENTITY1 (LMI1) gene of Arabidopsis is the causal gene underlying the l-D1locus. The classical okra leaf shape allele has a 133-bp tandem duplication in the promoter, correlated with elevated expression, whereas an 8-bp deletion in the third exon of the presumed wild-type normal allele causes a frame-shifted and truncated coding sequence. Our results indicate that subokra is the ancestral leaf shape of tetraploid cotton that gave rise to the okra allele and that normal is a derived mutant allele that came to predominate and define the leaf shape of cultivated cotton. Virus-induced gene silencing (VIGS) of the LMI1-like gene in an okra variety was sufficient to induce normal leaf formation. The developmental changes in leaves conferred by this gene are associated with a photosynthetic transcriptomic signature, substantiating its use by breeders to produce a superior cotton ideotype.
authors.affiliation: Department of Crop and Soil Sciences, North Carolina State University, Raleigh, NC 27695-7620.
authors.forename: Ryan J
authors.initials: RJ
authors.lastname: Andres
authors.affiliation: Donald Danforth Plant Science Center, St. Louis, MO 63132.
authors.forename: Viktoriya
authors.initials: V
authors.lastname: Coneva
authors.affiliation: Donald Danforth Plant Science Center, St. Louis, MO 63132.
authors.forename: Margaret H
authors.initials: MH
authors.lastname: Frank
authors.affiliation: Department of Crop and Soil Sciences, North Carolina State University, Raleigh, NC 27695-7620.
authors.forename: John R
authors.initials: JR
authors.lastname: Tuttle
authors.affiliation: Department of Crop and Soil Sciences, North Carolina State University, Raleigh, NC 27695-7620.|Plant Science Research Unit, United States Department of Agriculture-Agricultural Research Service, Raleigh, NC 27695-7620.
authors.forename: Luis Fernando
authors.initials: LF
authors.lastname: Samayoa
authors.affiliation: Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC 27695.
authors.forename: Sang-Won
authors.initials: SW
authors.lastname: Han
authors.affiliation: Department of Crop and Soil Sciences, North Carolina State University, Raleigh, NC 27695-7620.
authors.forename: Baljinder
authors.initials: B
authors.lastname: Kaur
authors.affiliation: Department of Crop and Soil Sciences, North Carolina State University, Raleigh, NC 27695-7620.
authors.forename: Linglong
authors.initials: L
authors.lastname: Zhu
authors.affiliation: Department of Crop and Soil Sciences, North Carolina State University, Raleigh, NC 27695-7620.
authors.forename: Hui
authors.initials: H
authors.lastname: Fang
authors.affiliation: Department of Crop and Soil Sciences, North Carolina State University, Raleigh, NC 27695-7620.
authors.forename: Daryl T
authors.initials: DT
authors.lastname: Bowman
authors.affiliation: Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC 27695.
authors.forename: Marcela
authors.initials: M
authors.lastname: Rojas-Pierce
authors.affiliation: Department of Crop and Soil Sciences, North Carolina State University, Raleigh, NC 27695-7620.|Department of Plant and Microbial Biology, North Carolina State University, Raleigh, NC 27695.
authors.forename: Candace H
authors.initials: CH
authors.lastname: Haigler
authors.affiliation: Cotton Incorporated, Cary, NC 27513.
authors.forename: Don C
authors.initials: DC
authors.lastname: Jones
authors.affiliation: Department of Crop and Soil Sciences, North Carolina State University, Raleigh, NC 27695-7620.|Plant Science Research Unit, United States Department of Agriculture-Agricultural Research Service, Raleigh, NC 27695-7620.
authors.forename: James B
authors.initials: JB
authors.lastname: Holland
authors.affiliation: Donald Danforth Plant Science Center, St. Louis, MO 63132; vasu_kuraparthy@ncsu.edu dchitwood@danforthcenter.org.
authors.forename: Daniel H
authors.initials: DH
authors.lastname: Chitwood
authors.affiliation: Department of Crop and Soil Sciences, North Carolina State University, Raleigh, NC 27695-7620; vasu_kuraparthy@ncsu.edu dchitwood@danforthcenter.org.
authors.forename: Vasu
authors.initials: V
authors.lastname: Kuraparthy
mesh_terms: D000595:Amino Acid Sequence / Q000235:genetics; D016368:Frameshift Mutation / Q000235:genetics; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant / Q000235:genetics; D003368:Gossypium / Q000235:genetics* / Q000502:physiology*; D018515:Plant Leaves / Q000235:genetics* / Q000502:physiology*; D011401:Promoter Regions, Genetic / Q000235:genetics; D014157:Transcription Factors / Q000235:genetics*
chemical_list: D014157:Transcription Factors
keywords: cotton; gene cloning; leaf shape; okra