Sperm Motility Defects and Infertility in Male Mice with a Mutation in Nsun7, a Member of the Sun Domain-Containing Family of Putative RNA Methyltransferases1

The linker of the nucleoskeleton and cytoskeleton (LINC) complex is formed by the conserved interactions between Sad-1 and UNC-84 (SUN) and Klarsicht, ANC-1, SYNE homology (KASH) domain proteins, providing a physical coupling between the nucleoskeleton and cytoskeleton that mediates the transfer of physical forces across the nuclear envelope. The LINC complex can perform distinct cellular functions by pairing various KASH domain proteins with the same SUN domain protein. For example, in Caenorhabditis elegans, SUN protein UNC-84 binds to two KASH proteins UNC-83 and ANC-1 to mediate nuclear migration and anchorage, respectively. In addition to distinct cytoplasmic domains, the luminal KASH domain also varies among KASH domain proteins of distinct functions. In this study, we combined in vivo C. elegans genetics and in silico molecular dynamics simulations to understand the relation between the length and amino acid composition of the luminal KASH domain, and the function of the SUN–KASH complex. We show that longer KASH domains can withstand and transfer higher forces and interact with the membrane through a conserved membrane proximal EEDY domain that is unique to longer KASH domains. In agreement with our models, our in vivo results show that swapping the KASH domains of ANC-1 and UNC-83, or shortening the KASH domain of ANC-1, both result in a nuclear anchorage defect in C. elegans.

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Combination of Korean Red Ginseng Extract and Hydrogen-Rich Water Improves Spermatogenesis and Sperm Motility in Male Mice

Chinese Journal of Integrative Medicine ◽

10.1007/s11655-019-3047-1 ◽

2020 ◽

Vol 26 (5) ◽

pp. 361-369 ◽

Cited By ~ 1

Author(s):

Ja Yoon Ku ◽

Min Jung Park ◽

Hyun Jun Park ◽

Nam Cheol Park ◽

Bo Sun Joo

Keyword(s):

Sperm Motility ◽

Male Mice ◽

Red Ginseng ◽

Korean Red Ginseng ◽

Ginseng Extract

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Telomeres and centromeres have interchangeable roles in promoting meiotic spindle formation

The Journal of Cell Biology ◽

10.1083/jcb.201409058 ◽

2015 ◽

Vol 208 (4) ◽

pp. 415-428 ◽

Cited By ~ 35

Author(s):

Alex Fennell ◽

Alfonso Fernández-Álvarez ◽

Kazunori Tomita ◽

Julia Promisel Cooper

Keyword(s):

Fission Yeast ◽

Nuclear Membrane ◽

Meiotic Prophase ◽

Meiotic Spindle ◽

The Sun ◽

Spindle Formation ◽

Domain Protein ◽

Bipolar Spindles ◽

Sun Domain ◽

Meiosis I

Telomeres and centromeres have traditionally been considered to perform distinct roles. During meiotic prophase, in a conserved chromosomal configuration called the bouquet, telomeres gather to the nuclear membrane (NM), often near centrosomes. We found previously that upon disruption of the fission yeast bouquet, centrosomes failed to insert into the NM at meiosis I and nucleate bipolar spindles. Hence, the trans-NM association of telomeres with centrosomes during prophase is crucial for efficient spindle formation. Nonetheless, in approximately half of bouquet-deficient meiocytes, spindles form properly. Here, we show that bouquet-deficient cells can successfully undergo meiosis using centromere–centrosome contact instead of telomere–centrosome contact to generate spindle formation. Accordingly, forced association between centromeres and centrosomes fully rescued the spindle defects incurred by bouquet disruption. Telomeres and centromeres both stimulate focal accumulation of the SUN domain protein Sad1 beneath the centrosome, suggesting a molecular underpinning for their shared spindle-generating ability. Our observations demonstrate an unanticipated level of interchangeability between the two most prominent chromosomal landmarks.

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Nonprogressive sperm motility is characteristic of most complete t haplotypes in the mouse

Genetics Research ◽

10.1017/s0016672300021613 ◽

1983 ◽

Vol 42 (2) ◽

pp. 151-157 ◽

Cited By ~ 10

Author(s):

Patricia Olds-Clarke

Keyword(s):

Sperm Motility ◽

Distal Region ◽

Complementation Group ◽

Motile Sperm ◽

Male Mice ◽

Wild Type ◽

Epididymal Sperm ◽

Distal Half ◽

The Mean

SUMMARYEpididymal sperm from male mice carrying tw32 (t12 complementation group) exhibit a peculiar nonprogressive type of motility called ‘dancing’; sperm from congenie wild-type mice do not. To determine whether this effect was unique to tw32 or common to all t haplotypes, sperm from mice carrying other t haplotypes were examined. A male was considered to have nonprogressive sperm if more than 20% of the motile sperm had nonprogressive trajectories. The mean percentage of nonprogressive but motile sperm for 33 wild-type and Brachyury males of various genetic backgrounds was 4. All males carrying tw12 (tw1 complementation group), tw5 or tw73, and 56% of males carrying t0 or tLub1 had nonprogressive motile sperm. Five per cent of males carrying t chromatin or a deletion in the proximal (to the centromere) half of the t complex had nonprogressive motile sperm, but all males carrying t chromatin in the distal half of the t complex had nonprogressive motile sperm. These observations suggest that the factor or factors causing nonprogressive sperm motility may be common to all complete t haplotypes, and located in the distal region of the t complex.

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Essential role for SUN5 in anchoring sperm head to the tail

eLife ◽

10.7554/elife.28199 ◽

2017 ◽

Vol 6 ◽

Cited By ~ 36

Author(s):

Yongliang Shang ◽

Fuxi Zhu ◽

Lina Wang ◽

Ying-Chun Ouyang ◽

Ming-Zhe Dong ◽

...

Keyword(s):

Male Infertility ◽

Nuclear Membrane ◽

Essential Role ◽

Sperm Head ◽

The Sun ◽

Male Mice ◽

Nuclear Dynamics ◽

Intracytoplasmic Injection

SUN (Sad1 and UNC84 domain containing)-domain proteins are reported to reside on the nuclear membrane playing distinct roles in nuclear dynamics. SUN5 is a new member of the SUN family, with little knowledge regarding its function. Here, we generated Sun5−/− mice and found that male mice were infertile. Most Sun5-null spermatozoa displayed a globozoospermia-like phenotype but they were actually acephalic spermatozoa. Additional studies revealed that SUN5 was located in the neck of the spermatozoa, anchoring sperm head to the tail, and without functional SUN5 the sperm head to tail coupling apparatus was detached from nucleus during spermatid elongation. Finally, we found that healthy heterozygous offspring could be obtained via intracytoplasmic injection of Sun5-mutated sperm heads for both male mice and patients. Our studies reveal the essential role of SUN5 in anchoring sperm head to the tail and provide a promising way to treat this kind of acephalic spermatozoa-associated male infertility.

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