TY - JOUR
T1 - In situ cryo-electron tomography reveals the asymmetric architecture of mammalian sperm axonemes
AU - Chen, Zhen
AU - Greenan, Garrett A.
AU - Shiozaki, Momoko
AU - Liu, Yanxin
AU - Skinner, Will M.
AU - Zhao, Xiaowei
AU - Zhao, Shumei
AU - Yan, Rui
AU - Yu, Zhiheng
AU - Lishko, Polina V.
AU - Agard, David A.
AU - Vale, Ronald D.
N1 - Publisher Copyright:
© 2023, The Author(s).
PY - 2023/3
Y1 - 2023/3
N2 - The flagella of mammalian sperm display non-planar, asymmetric beating, in contrast to the planar, symmetric beating of flagella from sea urchin sperm and unicellular organisms. The molecular basis of this difference is unclear. Here, we perform in situ cryo-electron tomography of mouse and human sperm, providing the highest-resolution structural information to date. Our subtomogram averages reveal mammalian sperm-specific protein complexes within the microtubules, the radial spokes and nexin–dynein regulatory complexes. The locations and structures of these complexes suggest potential roles in enhancing the mechanical strength of mammalian sperm axonemes and regulating dynein-based axonemal bending. Intriguingly, we find that each of the nine outer microtubule doublets is decorated with a distinct combination of sperm-specific complexes. We propose that this asymmetric distribution of proteins differentially regulates the sliding of each microtubule doublet and may underlie the asymmetric beating of mammalian sperm.
AB - The flagella of mammalian sperm display non-planar, asymmetric beating, in contrast to the planar, symmetric beating of flagella from sea urchin sperm and unicellular organisms. The molecular basis of this difference is unclear. Here, we perform in situ cryo-electron tomography of mouse and human sperm, providing the highest-resolution structural information to date. Our subtomogram averages reveal mammalian sperm-specific protein complexes within the microtubules, the radial spokes and nexin–dynein regulatory complexes. The locations and structures of these complexes suggest potential roles in enhancing the mechanical strength of mammalian sperm axonemes and regulating dynein-based axonemal bending. Intriguingly, we find that each of the nine outer microtubule doublets is decorated with a distinct combination of sperm-specific complexes. We propose that this asymmetric distribution of proteins differentially regulates the sliding of each microtubule doublet and may underlie the asymmetric beating of mammalian sperm.
UR - http://www.scopus.com/inward/record.url?scp=85145332591&partnerID=8YFLogxK
U2 - 10.1038/s41594-022-00861-0
DO - 10.1038/s41594-022-00861-0
M3 - Article
C2 - 36593309
AN - SCOPUS:85145332591
SN - 1545-9993
VL - 30
SP - 360
EP - 369
JO - Nature Structural and Molecular Biology
JF - Nature Structural and Molecular Biology
IS - 3
ER -