Generation and functional characterization of a conditional Pumilio2 null allele

Abstract

The highly conserved RNA binding protein PUF (Pumilio/FBF) family is present throughout eukaryotes from yeast to mammals, with critical roles in development, fertility and the nervous system. However, the function of the mammalian PUF family members remains underexplored. Our previous study reported that a gene-trap mutation of Pum2 results in a smaller testis but does not impact fertility and viability. Although the gene-trap mutation disrupted the key functional domain of PUM protein–PUM-HD (Pumilio homology domain), but still produced a chimeric Pum2-β-geo protein containing part of PUM2, raising a question if such a chimeric protein may provide any residual function or contribute to the reproductive phenotype. Here, we report the generation of a conditional PUM2 allele, when knocked out, producing no residual PUM2 and hence a complete loss-of-function allele. We also uncovered small but significant reduction of male fertility and viability in the mutants, suggesting requirement of PUM2 for male fertility and viability.

Keywords

RNA-binding protein / Pumilio2 / PUF / fertility / viability

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Acknowledgments

We would like to thank Dr. Takeshi Kurita for discussion and assistance throughout this project. We also thank Welcome Trust Sanger Institute and North-western Targeting and Transgenic Core facility for assistance in the generation of mutant mice. This work was supported by National Basic Research Program of China (973 program, 2013CB945201 and 2015CB-943002); National Science Foundation of China (81270737); Natural Science Foundation of Jiangsu Province (BK2012838); Provincial Innovation and Entrepreneurship Grant as well as NIH grant U01 HD045871. Funding for open access charge: Provincial Shuangchuang Program.

RIGHTS & PERMISSIONS

2018 2018 by the Journal of Biomedical Research.