CRISPR/Cas9-mediated mutation revealed cytoplasmic tail is dispensable for IZUMO1 function and male fertility.
IZUMO1 is a protein found in the head of spermatozoa that has been identified as essential for sperm-egg fusion. Its binding partner in the egg has been discovered (JUNO); however, the roles of several domains within IZUMO1 remain unexplored. One such domain is the C-terminus, which undergoes major phosphorylation changes in the cytoplasmic portion of the protein during rat epididymal transit. However, the cytoplasmic tail of IZUMO1 in many species is highly variable, ranging from 55 to one amino acid. Therefore, to understand the role of the cytoplasmic tail of IZUMO1 in mouse, we utilised the gene manipulation system of CRISPR/Cas9 to generate a point mutation resulting in a premature stop codon, producing mice with truncated IZUMO1. Mice without the cytoplasmic tail of IZUMO1 showed normal fertility but decreased the amount of protein, indicating that whilst this region is important for the expression level of IZUMO1, it is dispensable for fertilisation in the mouse.
Research Institute for Microbial Diseases.|Priority Research Centre in Reproductive ScienceDiscipline of Biological Sciences, Faculty of Science and IT, University of Newcastle, Callaghan, New South Wales, Australia.
Samantha A M
SA
Young
Research Institute for Microbial Diseases.
Haruhiko
H
Miyata
Research Institute for Microbial Diseases.
Yuhkoh
Y
Satouh
Research Institute for Microbial Diseases.|Graduate School of Pharmaceutical SciencesOsaka University, Suita, Osaka, Japan.
Masanaga
M
Muto
Institute for Biochemistry and Molecular BiologyUniversity of Southern Denmark, Odense, Denmark.
Martin R
MR
Larsen
Priority Research Centre in Reproductive ScienceDiscipline of Biological Sciences, Faculty of Science and IT, University of Newcastle, Callaghan, New South Wales, Australia.
R John
RJ
Aitken
Priority Research Centre in Reproductive ScienceDiscipline of Biological Sciences, Faculty of Science and IT, University of Newcastle, Callaghan, New South Wales, Australia.
Mark A
MA
Baker
Research Institute for Microbial Diseases ikawa@biken.osaka-u.ac.jp.|Graduate School of Pharmaceutical SciencesOsaka University, Suita, Osaka, Japan.
Masahito
M
Ikawa
D000595:Amino Acid Sequence; D000818:Animals; D064113:CRISPR-Cas Systems; D003593:Cytoplasm / Q000378:metabolism; D005298:Fertility / Q000235:genetics*; D005306:Fertilization / Q000502:physiology; D007136:Immunoglobulins / Q000235:genetics / Q000378:metabolism*; D008297:Male; D008565:Membrane Proteins / Q000235:genetics / Q000378:metabolism*; D051379:Mice; D009154:Mutation; D010766:Phosphorylation; D000072417:Protein Domains; D013084:Sperm-Ovum Interactions; D013094:Spermatozoa / Q000378:metabolism
D007136:Immunoglobulins; C498177:Izumo1 protein, mouse; D008565:Membrane Proteins