Takahiko Yamada1,2, Masaki Takechi1, Norisuke Yokoyama1, Yuichi Hiraoka3,4, Harumi Ishikubo3,4, Takako Usami3,4, Toshiko Furutera1, Yuki Taga5, Yoshikazu Hirate6, Masami Kanai-Azuma6, Tetsuya Yoda2, Kiyoko Ogawa-Goto5, Sachiko Iseki1. 1. Section of Molecular Craniofacial Embryology, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo, Japan. 2. Section of Maxillofacial Surgery, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo, Japan. 3. Laboratory of Genome Editing for Biomedical Research, Medical Research Institute, Tokyo Medical and Dental University (TMDU), Tokyo, Japan. 4. Laboratory of Molecular Neuroscience, Medical Research Institute, Tokyo Medical and Dental University (TMDU), Tokyo, Japan. 5. Nippi Research Institute of Biomatrix, Ibaraki, Japan. 6. Department of Experimental Animal Model for Human Disease, Graduate School of Medical and Dental Sciences, Tokyo Medical and Dental University (TMDU), Tokyo, Japan.
Abstract
BACKGROUND: Splicing factor 3B subunit 4 (SF3B4) is a causative gene of an acrofacial dysostosis, Nager syndrome. Although in vitro analyses of SF3B4 have proposed multiple noncanonical functions unrelated to splicing, less information is available based on in vivo studies using model animals. RESULTS: We performed expression and functional analyses of Sf3b4 in mice. The mouse Sf3b4 transcripts were found from two-cell stage, and were ubiquitously present during embryogenesis with high expression levels in several tissues such as forming craniofacial bones and brain. In contrast, expression of a pseudogene-like sequence of mouse Sf3b4 (Sf3b4_ps) found by in silico survey was not detected up to embryonic day 10. We generated a Sf3b4 knockout mouse using CRISPR-Cas9 system. The homozygous mutant mouse of Sf3b4 was embryonic lethal. The heterozygous mutant of Sf3b4 mouse (Sf3b4+/- ) exhibited smaller body size compared to the wild-type from postnatal to adult period, as well as homeotic posteriorization of the vertebral morphology and flattened calvaria. The flattened calvaria appears to be attributable to mild microcephaly due to a lower cell proliferation rate in the forebrain. CONCLUSIONS: Our study suggests that Sf3b4 controls anterior-posterior patterning of the axial skeleton and guarantees cell proliferation for forebrain development in mice.
BACKGROUND:Splicing factor 3B subunit 4 (SF3B4) is a causative gene of an acrofacial dysostosis, Nager syndrome. Although in vitro analyses of SF3B4 have proposed multiple noncanonical functions unrelated to splicing, less information is available based on in vivo studies using model animals. RESULTS: We performed expression and functional analyses of Sf3b4 in mice. The mouseSf3b4 transcripts were found from two-cell stage, and were ubiquitously present during embryogenesis with high expression levels in several tissues such as forming craniofacial bones and brain. In contrast, expression of a pseudogene-like sequence of mouseSf3b4 (Sf3b4_ps) found by in silico survey was not detected up to embryonic day 10. We generated a Sf3b4 knockout mouse using CRISPR-Cas9 system. The homozygous mutant mouse of Sf3b4 was embryonic lethal. The heterozygous mutant of Sf3b4mouse (Sf3b4+/- ) exhibited smaller body size compared to the wild-type from postnatal to adult period, as well as homeotic posteriorization of the vertebral morphology and flattened calvaria. The flattened calvaria appears to be attributable to mild microcephaly due to a lower cell proliferation rate in the forebrain. CONCLUSIONS: Our study suggests that Sf3b4 controls anterior-posterior patterning of the axial skeleton and guarantees cell proliferation for forebrain development in mice.
Authors: Aaron L Slusher; Jeongjin J Kim; Mark Ribick; Jesse Pollens-Voigt; Armand Bankhead; Phillip L Palmbos; Andrew T Ludlow Journal: Mol Cancer Res Date: 2022-10-04 Impact factor: 6.333