1. Chromosomes and Gene Expression
Download icon

Gene regulation: A transcriptional switch controls meiosis

  1. A Elizabeth Hildreth
  2. Karen M Arndt  Is a corresponding author
  1. University of Pittsburgh, United States
Insight
Cite as: eLife 2017;6:e31911 doi: 10.7554/eLife.31911
1 figure

Figures

Transcriptional switching between two mRNA transcripts regulates the assembly of the kinetochore during meiosis.

(A) During prophase, homologous chromosomes undergo recombination to exchange genetic information (right). The kinetochore must be dismantled during this time so that chromosomes do not prematurely separate. Cells do this by limiting the availability of a subunit of the kinetochore called Ndc80 (left top). First, Ume6-Ime1 binds to an upstream promoter (thick black arrow) and the DNA is transcribed to produce an extended mRNA transcript named NDC80luti. This process also results in the deposition of methylation marks (small blue circles) on histones (brown cyclinders). Enzymes called histone deacetylases (Set3 and Rpd3S) bind these marks and deacetylate the histones; the end result is to prevent the gene for Ndc80 (lilac rectangle) from being transcribed to produce a short mRNA transcript called NDC80ORF. Reduced transcription from the NDC80ORF promoter is indicated by the thinner black arrow. Additional regulation comes from upstream open reading frames (uORFs) in the extended transcript; the translation of these regions by the ribosome prevents translation reinitiation taking place at the NDC80 start codon (left bottom). (B) Following prophase, the kinetochore reassembles for chromosome segregation (right). Another transcription factor, Ndt80, binds the canonical NDC80 promoter (left top), and the DNA is transcribed to produce the shorter mRNA transcript. Translation of this transcript produces functional Ndc80 protein (left bottom), allowing the kinetochore to assemble and the chromosomes to segregate. Black arrows indicate direction of movement.

Download links

A two-part list of links to download the article, or parts of the article, in various formats.

Downloads (link to download the article as PDF)

Download citations (links to download the citations from this article in formats compatible with various reference manager tools)

Open citations (links to open the citations from this article in various online reference manager services)