Transposable elements (TEs), including endogenous retroelements (ERVs), are widely dispersed and deeply embedded in our DNA. While these elements are silenced in somatic cells to support normal cell function, they undergo waves of programmed activation during pre-implantation development. The full complement of proteins involved in ERV regulation, and the functional consequences of ERV silencing during developmental differentiation, remain poorly understood.

Our work in this area has led to new insights into how retroelements are recognized for silencing, the impact of retroelement silencing on developmental differentiation, and how the same proteins have been used in different species to silence different retroelement sequences.

The goals of this arm of our research program are to:

• Gain deep molecular insights into how different families of ERVs are silenced in different species

• Identify the complete parts list of proteins involved in ERV silencing in the human genome

• Explore new concepts regarding the molecular impact of ERV regulation during development and in disease

Key Publications

TASOR expression in naïve embryonic stem cells safeguards their developmental potential
Pinzon-Arteaga CA*, O’Hara R*, Mazzagati A, Ballard E, Hu Y, Pan A, Schmitz DA, Wei Y, Sakurai M, Ly P, Banaszynski LA‡, Wu J‡. (2024) Cell Reports 43, 114887. *These authors contributed equally. ‡ Co-corresponding authors [paper]

Loss of heterochromatin at endogenous retroviruses creates competition for transcription factor binding
O’Hara R and Banaszynski LA. (2022) bioRxiv. [paper] 

Histone H3.3 is required for endogenous retroviral element silencing in embryonic stem cells
Elsässer SJ*, Noh K-M, Diaz N, Allis CD, Banaszynski LA.* (2015) Nature 522, 240-244. *equal contribution [paper]