The ADAXIALIZED LEAF1 gene functions in leaf and embryonic pattern formation in rice

Dev Biol. 2009 Oct 15;334(2):345-54. doi: 10.1016/j.ydbio.2009.07.042. Epub 2009 Aug 6.

Abstract

The adaxial-abaxial axis in leaf primordia is thought to be established first and is necessary for the expansion of the leaf lamina along the mediolateral axis. To understand axis information in leaf development, we isolated the adaxialized leaf1 (adl1) mutant in rice, which forms abaxially rolled leaves. adl1 leaves are covered with bulliform-like cells, which are normally distributed only on the adaxial surface. An adl1 double mutant with the adaxially snowy leaf mutant, which has albino cells that specifically appear in the abaxial mesophyll tissue, indicated that adl1 leaves show adaxialization in both epidermal and mesophyll tissues. The expression of HD-ZIPIII genes in adl1 mutant increased in mature leaves, but not in the young primordia or the SAM. This indicated that ADL1 may not be directly involved in determining initial leaf polarity, but rather is associated with the maintenance of axis information. ADL1 encodes a plant-specific calpain-like cysteine proteinase orthologous to maize DEFECTIVE KERNEL1. Furthermore, we identified intermediate and strong alleles of the adl1 mutant that generate shootless embryos and globular-arrested embryos with aleurone layer loss, respectively. We propose that ADL1 plays an important role in pattern formation of the leaf and embryo by promoting proper epidermal development.

Publication types

  • Comparative Study
  • Research Support, Non-U.S. Gov't

MeSH terms

  • Alleles
  • Amino Acid Sequence
  • Body Patterning / physiology*
  • Calpain / genetics
  • Calpain / physiology*
  • Conserved Sequence
  • Gene Expression Profiling
  • Gene Expression Regulation, Developmental
  • Gene Expression Regulation, Plant
  • Genes, Recessive
  • Homeodomain Proteins / physiology
  • Molecular Sequence Data
  • Oryza / anatomy & histology
  • Oryza / embryology
  • Oryza / genetics*
  • Phenotype
  • Plant Epidermis / growth & development*
  • Plant Epidermis / ultrastructure
  • Plant Leaves / growth & development
  • Plant Leaves / ultrastructure
  • Plant Proteins / genetics
  • Plant Proteins / physiology*
  • Seeds / growth & development
  • Seeds / ultrastructure
  • Sequence Alignment
  • Sequence Homology, Amino Acid

Substances

  • Homeodomain Proteins
  • Plant Proteins
  • Calpain