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bioRxiv · 10.1101/541995

Murine Surf4 is essential for early embryonic development

Emmer, B. T.·Lascuna, P. J.·Kotnik, E.·Saunders, T.·Khoriaty, R.·Ginsburg, D.
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Abstract

Newly synthesized proteins co-translationally inserted into the endoplasmic reticulum (ER) lumen may be recruited into anterograde transport vesicles by their association with specific cargo receptors. We recently identified a role for the cargo receptor SURF4 in facilitating the secretion of PCSK9 in cultured cells. To examine the function of SURF4 in vivo, we used CRISPR/Cas9-mediated gene editing to generate mice with germline loss-of-function mutations in Surf4. Surf4+/- mice exhibited grossly normal appearance, behavior, body weight, fecundity, and organ development and demonstrated no significant alterations in circulating plasma levels of PCSK9, apolipoprotein B, or total cholesterol. Surf4-/- mice exhibit embryonic lethality, with complete loss of all Surf4-/- offspring between embryonic days 3.5 and 9.5. Taken together with the much milder phenotypes of PCSK9 or apolipoprotein B deficiency in mice, these findings imply the existence of additional SURF4 cargoes or functions that are essential for murine early embryonic development.

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Emmer, B. T., Lascuna, P. J., Kotnik, E., Saunders, T., Khoriaty, R., Ginsburg, D.. 2019-02-07. Murine Surf4 is essential for early embryonic development. https://doi.org/10.1101/541995

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