The over-expression of two transcription factors, ABS5/bHLH30 and ABS7/MYB101, leads to upwardly curly leaves

PLoS One. 2014 Sep 30;9(9):e107637. doi: 10.1371/journal.pone.0107637. eCollection 2014.

Abstract

Proper leaf development is essential for plant growth and development, and leaf morphogenesis is under the control of intricate networks of genetic and environmental cues. We are interested in dissecting these regulatory circuits genetically and report here the isolation of two Arabidopsis dominant mutants, abnormal shoot5-1D (abs5-1D) and abs7-1D identified through activation tagging screens. Both abs5-1D and abs7-1D display an intriguing upwardly curly leaf phenotype. Molecular cloning showed that the elevated expression of a bHLH transcription factor ABS5/T5L1/bHLH30 or a MYB transcription factor ABS7/MYB101 is the cause for the abnormal leaf phenotypes found in abs5-1D or abs7-1D, respectively. Protoplast transient expression assays confirmed that both ABS5/T5L1 and ABS7/MYB101 are targeted to the nucleus. Interestingly, the expression domains of auxin response reporter DR5::GUS were abnormal in leaves of abs5-1D and ABS5/T5L1 over-expression lines. Moreover, cotyledon venation analysis showed that more areoles and free-ending veins are formed in abs5-1D. We found that the epidermis-specific expressions of ABS5/T5L1 or ABS7/MYB101 driven by the Arabidopsis Meristem Layer 1 promoter (PAtML1) were sufficient to recapitulate the curly leaf phenotype of abs5-1D or abs7-1D. In addition, PAtML1::ABS5 lines exhibited similar changes in DR5::GUS expression patterns as those found in 35S-driven ABS5/T5L1 over-expression lines. Our work demonstrated that enhanced expressions of two transcription factors, ABS5/T5L1 and ABS7/MYB101, are able to alter leaf lamina development and reinforce the notion that leaf epidermis plays critical roles in regulating plant organ morphogenesis.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • ATP-Binding Cassette Transporters / genetics
  • ATP-Binding Cassette Transporters / metabolism*
  • Arabidopsis / anatomy & histology
  • Arabidopsis / metabolism*
  • Arabidopsis Proteins / genetics
  • Arabidopsis Proteins / metabolism*
  • Basic Helix-Loop-Helix Transcription Factors / genetics
  • Basic Helix-Loop-Helix Transcription Factors / metabolism*
  • Cloning, Molecular
  • Gene Expression
  • Gene Expression Regulation, Plant
  • Phenotype
  • Plant Leaves / anatomy & histology
  • Plant Leaves / metabolism*
  • Transcription Factors / genetics
  • Transcription Factors / metabolism*
  • Transcriptional Activation
  • Yeasts

Substances

  • ATM1 protein, Arabidopsis
  • ATP-Binding Cassette Transporters
  • Arabidopsis Proteins
  • Basic Helix-Loop-Helix Transcription Factors
  • MYB101 protein, Arabidopsis
  • Transcription Factors
  • bHLH30 protein, Arabidopsis

Grant support

This work was supported by funding from the National Natural Science Foundation of China (31071073, 31170219 to F.Y., 31100864 to X.L. and 31300988 to Y.Q.) and by grants from the Natural Science Foundation of Shaanxi Province, China (2011JQ3004 to X.L., 2012JQ3015 to Y.Q., 2452013QN086 to J.S. and 2013JQ3014 to L.A.). The funders had no role in study design, data collection and analysis, decision to publish, or preparation of the manuscript.