Identification of Novel Binding Partners for Transcription Factor Emx2

  • Jennifer A. Groves
  • Cody Gillman
  • Cierra N. DeLay
  • Todd T. KrollEmail author


The mammalian homolog of Drosophila empty spiracles 2 (Emx2) is a homeobox transcription factor that plays central roles in early development of the inner ear, pelvic and shoulder girdles, cerebral cortex, and urogenital organs. The role for Emx2 is best understood within the context of the development of the neocortical region of the cortex, where Emx2 is expressed in a high posterior-medial to low anterior-lateral gradient that regulates the partitioning of the neocortex into different functional fields that perform discrete computational tasks. Despite several lines of evidence demonstrating an Emx2 concentration-dependent mechanism for establishing functional areas within the developing neocortex, little is known about how Emx2 physically carries out this role. Although several binding partners for Emx2 have been identified (including Sp8, eIF4E, and Pbx1), no screens have been used to identify potential protein binding partners for this protein. We utilized a yeast two-hybrid screen using a library constructed from embryonic mouse cDNA in an attempt to identify novel binding partners for Emx2. This initial screen isolated two potential Emx2-binding partner proteins, Cnot6l and QkI-7. These novel Emx2-binding proteins are involved in multiple levels of mRNA metabolism that including splicing, mRNA export, translation, and destruction, thus making them interesting targets for further study.


Emx2 Cnot6l Quaking Arealization Development 



Mouse tissue to generate the yeast two-hybrid library was kindly provided by Dennis O’Leary at the Salk Institute for Biological Studies.


Funds to conduct this work were provided by a Single Investigator Award (#19482) from the Research Corporation for Science Advancement, the Central Washington University Science Honors Program, the Central Washington University STEP program, a Central Washington University COTS Undergrad research grant, and the School of Graduate Studies and Research at Central Washington University, Ellensburg, Washington.

Compliance with Ethical Standards

Conflict of interest

All authors declare that they have no conflict of interest.

Research Involving Human and Animal Participants

All applicable international, national, and/or institutional guidelines for the care and use of animals were followed. This article does not contain any studies with human participants by any of the authors.


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© Springer Science+Business Media, LLC, part of Springer Nature 2019

Authors and Affiliations

  1. 1.Department of ChemistryCentral Washington UniversityEllensburgUSA
  2. 2.Division of Chemistry and Chemical EngineeringCalifornia Institute of TechnologyPasadenaUSA

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