Related Experiment Video
Updated: Jul 11, 2026
10:08
Experimental Design for Laser Microdissection RNA-Seq: Lessons from an Analysis of Maize Leaf Development
Published on: March 5, 2017
Regulation of SHOOT MERISTEMLESS genes via an upstream-conserved noncoding sequence coordinates leaf development
Naoyuki Uchida1, Brad Townsley, Kook-Hyun Chung
1Section of Plant Biology, University of California, Davis, CA 95616, USA.
Summary
Plant leaf development is regulated by conserved noncoding sequences controlling SHOOT MERISTEMLESS (STM) gene expression. These sequences manage gene repression and reestablishment, impacting leaf formation pathways.
Area of Science:
- Plant developmental biology
- Molecular genetics
Background:
- Class 1 KNOTTED1-LIKE HOMEOBOX (KNOX1) genes, including SHOOT MERISTEMLESS (STM) in Arabidopsis, are crucial for maintaining indeterminate shoot apical meristem fate.
- Down-regulation of STM genes in initiating leaf primordia signifies a switch to determinate fate, with persistent repression in simple leaves and reestablishment in compound leaves.
Purpose of the Study:
- To investigate the regulatory mechanisms governing STM gene expression during plant leaf development.
- To identify conserved noncoding sequences involved in STM gene regulation across different plant species.
Main Methods:
- Identification of conserved noncoding sequences in the 5' upstream region of STM genes.
- Functional analysis of these sequences in regulating STM expression during leaf development.
- Investigation of the interplay between STM regulation and the ASYMMETRIC LEAVES1/2 (AS1/2) pathway.
Main Results:
- Two evolutionarily conserved noncoding sequences were identified in the STM gene's 5' upstream region.
- One identified element regulates persistent repression and/or reestablishment of STM expression in developing leaves, but not initial down-regulation.
- This regulation is developmentally significant and linked to the ASYMMETRIC LEAVES1/2 (AS1/2) gene expression pathway.
Conclusions:
- A conserved noncoding sequence acts as a key regulatory point in STM gene expression during leaf development.
- This finding provides insights into the molecular mechanisms controlling leaf morphology, particularly the differences between simple and compound leaves.
- The study highlights the importance of noncoding regulatory elements in plant development.
Related Concept Videos
03:02Primary and Secondary Growth in Roots and Shoots
Vascular plants, which account for over 90% of the Earth’s vegetation, all undergo primary growth—which lengthens roots and shoots. Many land plants, notably woody plants, also undergo secondary growth—which thickens roots and shoots.
02:24Regulation of Expression Occurs at Multiple Steps
Gene expression can be regulated at almost every step from gene to protein. Transcription is the step that is most commonly regulated. This involves the binding of proteins to short regulatory sequences on the DNA. This association can either promote or inhibit the transcription of a gene associated with the respective sequence.
Transcription results in the generation of precursor (pre-mRNA) that consists of both exons and introns, which needs further processing before being translated to a...
Transcription results in the generation of precursor (pre-mRNA) that consists of both exons and introns, which needs further processing before being translated to a...
02:24Regulation of Expression Occurs at Multiple Steps
Gene expression can be regulated at almost every step from gene to protein. Transcription is the step that is most commonly regulated. This involves the binding of proteins to short regulatory sequences on the DNA. This association can either promote or inhibit the transcription of a gene associated with the respective sequence.
Transcription results in the generation of precursor (pre-mRNA) that consists of both exons and introns, which needs further processing before being translated to a...
Transcription results in the generation of precursor (pre-mRNA) that consists of both exons and introns, which needs further processing before being translated to a...
01:23Regulation of Expression at Multiple Steps
The gene expression in cells is regulated at different stages: (i) transcription, (ii) RNA processing, (iii) RNA localization, and (iv) translation. Transcriptional regulation is mediated by regulatory proteins such as transcription factors, activators, or repressors—these control gene expression by initiating or inhibiting the transcription of genes. Once a precursor or pre-mRNA is produced, it undergoes post-transcriptional modification, including 5' capping, splicing, and the addition of a...
02:02Cis-regulatory Sequences
Cis-regulatory sequences are short fragments of non-coding DNA that are present on the same chromosomes as the genes that they regulate. These fragments serve as binding sites for transcriptional regulators, proteins that are responsible for controlling gene transcription and differential gene expression across cell types in eukaryotes. Cis-regulatory sequences can be close to the gene of interest or thousands of bases away in the DNA sequence; however, those sequences that are further away are...
02:02Cis-regulatory Sequences
Cis-regulatory sequences are short fragments of non-coding DNA that are present on the same chromosomes as the genes that they regulate. These fragments serve as binding sites for transcriptional regulators, proteins that are responsible for controlling gene transcription and differential gene expression across cell types in eukaryotes. Cis-regulatory sequences can be close to the gene of interest or thousands of bases away in the DNA sequence; however, those sequences that are further away are...