title: Auxin signaling modules regulate maize inflorescence architecture.
abstract: In plants, small groups of pluripotent stem cells called axillary meristems are required for the formation of the branches and flowers that eventually establish shoot architecture and drive reproductive success. To ensure the proper formation of new axillary meristems, the specification of boundary regions is required for coordinating their development. We have identified two maize genes, BARREN INFLORESCENCE1 and BARREN INFLORESCENCE4 (BIF1 and BIF4), that regulate the early steps required for inflorescence formation. BIF1 and BIF4 encode AUXIN/INDOLE-3-ACETIC ACID (Aux/IAA) proteins, which are key components of the auxin hormone signaling pathway that is essential for organogenesis. Here we show that BIF1 and BIF4 are integral to auxin signaling modules that dynamically regulate the expression of BARREN STALK1 (BA1), a basic helix-loop-helix (bHLH) transcriptional regulator necessary for axillary meristem formation that shows a striking boundary expression pattern. These findings suggest that auxin signaling directly controls boundary domains during axillary meristem formation and define a fundamental mechanism that regulates inflorescence architecture in one of the most widely grown crop species.
authors.affiliation: Waksman Institute, Rutgers University, Piscataway, NJ 08854-8020;
authors.forename: Mary
authors.initials: M
authors.lastname: Galli
authors.affiliation: Waksman Institute, Rutgers University, Piscataway, NJ 08854-8020;
authors.forename: Qiujie
authors.initials: Q
authors.lastname: Liu
authors.affiliation: Department of Biology, University of Washington, Seattle, WA 98195;
authors.forename: Britney L
authors.initials: BL
authors.lastname: Moss
authors.affiliation: Department of Biological Sciences, California State University, Long Beach, CA 90840; Division of Environmental Biology, National Science Foundation, Arlington, VA 22230;
authors.forename: Simon
authors.initials: S
authors.lastname: Malcomber
authors.affiliation: Waksman Institute, Rutgers University, Piscataway, NJ 08854-8020;
authors.forename: Wei
authors.initials: W
authors.lastname: Li
authors.affiliation: Section of Cell and Developmental Biology, University of California, San Diego, La Jolla, CA 92093-0116;
authors.forename: Craig
authors.initials: C
authors.lastname: Gaines
authors.affiliation: Waksman Institute, Rutgers University, Piscataway, NJ 08854-8020;
authors.forename: Silvia
authors.initials: S
authors.lastname: Federici
authors.affiliation: Waksman Institute, Rutgers University, Piscataway, NJ 08854-8020;
authors.forename: Jessica
authors.initials: J
authors.lastname: Roshkovan
authors.affiliation: Pioneer Hi-Bred International, Johnston, IA 50131;
authors.forename: Robert
authors.initials: R
authors.lastname: Meeley
authors.affiliation: Department of Biology, University of Washington, Seattle, WA 98195;
authors.forename: Jennifer L
authors.initials: JL
authors.lastname: Nemhauser
authors.affiliation: Waksman Institute, Rutgers University, Piscataway, NJ 08854-8020; Department of Plant Biology and Pathology, Rutgers University, New Brunswick, NJ 08901 agallavotti@waksman.rutgers.edu.
authors.forename: Andrea
authors.initials: A
authors.lastname: Gallavotti
mesh_terms: D001499:Bayes Theorem; D003001:Cloning, Molecular; D019295:Computational Biology; D017931:DNA Primers / Q000235:genetics; D024202:Electrophoretic Mobility Shift Assay; D035264:Flowers / Q000166:cytology* / Q000254:growth & development; D018507:Gene Expression Regulation, Developmental / Q000235:genetics / Q000502:physiology*; D018506:Gene Expression Regulation, Plant / Q000235:genetics / Q000502:physiology*; D017403:In Situ Hybridization; D007210:Indoleacetic Acids / Q000378:metabolism*; D018519:Meristem / Q000254:growth & development / Q000378:metabolism*; D008957:Models, Genetic; D010802:Phylogeny; D010940:Plant Proteins / Q000235:genetics / Q000378:metabolism; D060888:Real-Time Polymerase Chain Reaction; D015398:Signal Transduction / Q000502:physiology*; D003313:Zea mays / Q000254:growth & development*
chemical_list: D017931:DNA Primers; D007210:Indoleacetic Acids; D010940:Plant Proteins
keywords: auxin signaling; axillary meristems; boundary domains; inflorescence development; maize