scholarly journals Rimklb mutation causes male infertility in mice

2021 ◽  
Vol 11 (1) ◽  
Author(s):  
Koji Maekura ◽  
Satoshi Tsukamoto ◽  
Michiko Hamada-Kanazawa ◽  
Masaoki Takano
Keyword(s):  
Male Infertility ◽  
Ribosomal Protein ◽  
Mutant Mouse ◽  
Physiological Role ◽  
Seminiferous Tubules ◽  
Vitro Fertilization ◽  
Ribosomal Protein S6 ◽  
Key Factor ◽  
Transcriptional Pathway

AbstractRimklb is a mammalian homologue of the E. coli enzyme RimK, which catalyzes addition of glutamic acid to the ribosomal protein S6. To date, no previous studies have shown any physiological role for Rimklb in mammals. In this study, using Western blotting, we found that Rimklb is distributed and expressed in mouse testis and heart. Rimklb was subsequently localized to the testicular Leydig cells using immunohistochemistry with an anti-Rimklb antibody. We generated a Rimklb mutant mouse in which a three-base deletion results in deletion of Ala 29 and substitution of Leu 30 with Val, which we named the RimklbA29del, L30V mutant mouse. RimklbA29del, L30V mutant mice show a decrease in testicular size and weight, and in vitro fertilization demonstrates complete male infertility. Furthermore, we found that a key factor in the mammalian target of the rapamycin/ribosomal protein S6 transcriptional pathway is hyperphosphorylated in the seminiferous tubules of the mutant testis. We conclude that Rimklb has important roles that include spermatogenesis in seminiferous tubules. In summary, male RimklbA29del, L30V mice are infertile.

scholarly journals Modern achievements of the development of scientific research at obtaining in vitro sheep embryos

2020 ◽  
Vol 22 (93) ◽  
pp. 60-68
Author(s):  
O. M. Sharan ◽  
V. Yu. Stefanyk ◽  
S. G. Shalovylo
Keyword(s):  
In Vitro Fertilization ◽  
Embryo Culture ◽  
Biologically Active ◽  
In Vitro Production ◽  
Embryo Production ◽  
Vitro Fertilization ◽  
Maturation In Vitro ◽  
Key Factor ◽  
Vitro Production

New literature data on research aimed at improving the in vitro production of sheep embryos presents in the article. An analysis of the achievements of scientists from different countries to increase the efficiency of the main stages of embryo production in vitro: maturation of oocytes in vitro, their in vitro fertilization and in vitro embryo culture. In the literature experience has shown that the efficiency of oocyte maturation in vitro is significantly influenced by the experience and qualifications of scientists, the age of the egg donor, the improvement of the environment by adding roscovitin to inhibit meiosis, α-linolenic acid, cerium dioxide nanoparticles (CeO2 NPs) and sericin to accelerate nuclear maturation and increase the number of oocytes of the second meiotic metaphase (MII). The main factors influencing the effectiveness of in vitro fertilization have been identified, and the parameters of the limited time of fertilization ability of sperm and the ability of oocytes to fertilize, which is called the “fertile span”, have been determined. The main effective medium that increases the effectiveness of in vitro fertilization – synthetic oviduct fluid (SOF) with the addition of heparin and serum of cattle or sheep. The main parameters of sheep embryo culture in vitro are presented with the definition of the most commonly used media and their influence on embryonic development. Potential ways to improve the production of sheep embryos in vitro with the determination of morphological evaluation of categories of oocytes, methods of synchronization of their maturation in vitro are also highlighted. At the same time, literature data on the synchronization of oocyte-cumulus complexes with the use of a large number of inhibitors of meiotic division are presented, which according to many scientists may be a key factor in improving the efficiency of sheep embryo production in vitro. In addition, the results of studies of many scientists on the expansion of the fertile gap of oocytes of sheep cultured in vitro using certain biologically active substances were analyzed. In conclusion, the prospect of using the technology of in vitro production of sheep embryos in biomedical research is highlighted.

scholarly journals Testis-Specific SEPT12 Expression Affects SUN Protein Localization and is Involved in Mammalian Spermiogenesis

2019 ◽  
Vol 20 (5) ◽  
pp. 1163 ◽  
Author(s):  
Chung-Hsin Yeh ◽  
Ya-Yun Wang ◽  
Shi-Kae Wee ◽  
Mei-Feng Chen ◽  
Han-Sun Chiang ◽  
...  
Keyword(s):  
Male Infertility ◽  
Nuclear Membrane ◽  
Sperm Count ◽  
Protein Localization ◽  
Cancer Cell Line ◽  
Structural Defects ◽  
Preimplantation Embryos ◽  
Severe Oligozoospermia ◽  
Vitro Fertilization

Male infertility is observed in approximately 50% of all couples with infertility. Intracytoplasmic sperm injection (ICSI), a conventional artificial reproductive technique for treating male infertility, may fail because of a severe low sperm count, immotile sperm, immature sperm, and sperm with structural defects and DNA damage. Our previous studies have revealed that mutations in the septin (SEPT)-coding gene SEPT12 cause teratozoospermia and severe oligozoospermia. These spermatozoa exhibit morphological defects in the head and tail, premature chromosomal condensation, and nuclear damage. Sperm from Sept12 knockout mice also cause the developmental arrest of preimplantation embryos generated through in vitro fertilization and ICSI. Furthermore, we found that SEPT12 interacts with SPAG4, a spermatid nuclear membrane protein that is also named SUN4. Loss of the Spag4 allele in mice also disrupts the integration nuclear envelope and reveals sperm head defects. However, whether SEPT12 affects SPAG4 during mammalian spermiogenesis remains unclear. We thus conducted this study to explore this question. First, we found that SPAG4 and SEPT12 exhibited similar localizations in the postacrosomal region of elongating spermatids and at the neck of mature sperm through isolated murine male germ cells. Second, SEPT12 expression altered the nuclear membrane localization of SPAG4, as observed through confocal microscopy, in a human testicular cancer cell line. Third, SEPT12 expression also altered the localizations of nuclear membrane proteins: LAMINA/C in the cells. This effect was specifically due to the expression of SEPT12 and not that of SEPT1, SEPT6, SEPT7, or SEPT11. Based on these results, we suggest that SEPT12 is among the moderators of SPAG4/LAMIN complexes and is involved in the morphological formation of sperm during mammalian spermiogenesis.

A modern view of male infertility

1994 ◽  
Vol 6 (1) ◽  
pp. 93 ◽  
Author(s):  
SJ Silber
Keyword(s):  
Male Infertility ◽  
Y Chromosome ◽  
Obstructive Azoospermia ◽  
Male Factor Infertility ◽  
Male Factor ◽  
Sperm Retrieval ◽  
Modern Approach ◽  
Vitro Fertilization ◽  
Defective Spermatogenesis

It is archaic to view male factor infertility today separately from in vitro fertilization (IVF) and treatment of the female partner. Oligoasthenozoospermia may be an inherited condition (most likely on the Y chromosome), and is refractory to any treatment of the male including hormones and varicocelectomy. IVF technology is the only justifiable approach for achieving a pregnancy in these couples. The reasons for this view and the suggested modern approach to couples with oligoasthenozoospermia are outlined in this review. However, obstructive azoospermia is different as it can be successfully corrected with microsurgery in over 90% of men. When it cannot be corrected, as in congenital absence of vas, microsurgical sperm retrieval combined with IVF can still be highly effective in producing pregnancy with sperm from the husband. The most important arena for research into male infertility in the next decade will be to map out the deletions on the Y chromosome that might result in defective spermatogenesis, and which probably cause most cases of non-obstructive male factor infertility.

scholarly journals Mice Deficient in the Axonemal Protein Tektin-t Exhibit Male Infertility and Immotile-Cilium Syndrome Due to Impaired Inner Arm Dynein Function

2004 ◽  
Vol 24 (18) ◽  
pp. 7958-7964 ◽  
Author(s):  
Hiromitsu Tanaka ◽  
Naoko Iguchi ◽  
Yoshiro Toyama ◽  
Kouichi Kitamura ◽  
Tohru Takahashi ◽  
...  
Keyword(s):  
Physiological Role ◽  
Electron Microscopic Examination ◽  
Electron Microscopic ◽  
Vitro Fertilization ◽  
Homozygous Mutant ◽  
Causal Genes ◽  
And Function ◽  
Ciliary Dyskinesia

ABSTRACT The haploid germ cell-specific Tektin-t protein is a member of the Tektin family of proteins that form filaments in flagellar, ciliary, and axonemal microtubules. To investigate the physiological role of Tektin-t, we generated mice with a mutation in the tektin-t gene. The homozygous mutant males were infertile, while the females were fully fertile. Sperm morphology and function were abnormal, with frequent bending of the sperm flagella and marked defects in motility. In vitro fertilization assays showed that the defective spermatozoa were able to fertilize eggs. Electron microscopic examination showed that the dynein inner arm structure was disrupted in the sperm flagella of tektin-t-deficient mice. Furthermore, homozygous mutant mice had functionally defective tracheal cilia, as evidenced by altered dynein arm morphology. These results indicate that Tektin-t participates in dynein inner arm formation or attachment and that the loss of Tektin-t results in impaired motility of both flagella and cilia. Therefore, the tektin-t gene is one of the causal genes for immotile-cilium syndrome/primary ciliary dyskinesia.

Physiological levels of immunoreactive ANH-like peptides in human follicular fluid

1989 ◽  
Vol 121 (4) ◽  
pp. 578-580 ◽  
Author(s):  
J. A. Sundsfjord ◽  
F. Forsdahl ◽  
G. Thibault
Keyword(s):  
Fluid Dynamics ◽  
In Vitro Fertilization ◽  
Young Women ◽  
Follicular Fluid ◽  
Physiological Role ◽  
Plasma Samples ◽  
Human Follicular Fluid ◽  
Vitro Fertilization ◽  
Follicular Maturation

Abstract. The concentrations of immunoreactive C-terminal (ANH-(99-126)) and N-terminal (ANH-(1-98)) portions of pro-ANH were measured in follicular fluid and plasma samples from 9 young women undergoing in vitro fertilization. ANH-(99-126) and ANH-(1-98)-like immunoreactivity levels in plasma were 6.0–25.4 (mean 12.2) pmol/1 and 184–427 (mean 300) pmol/1, respectively, whereas the corresponding levels in follicular fluid were 3.8–8.0 (mean 4.9) pmol/1 and 169–385 (mean 262) pmol/1. The concentrations of both ANH-like peptides were consistently lower (p < 0.01) in the follicular fluid than in the matched plasma samples, but within the variation found in plasma controls. It is concluded that ANH-like peptides in the follicular fluid, whether secreted locally or derived from circulating ANH, might play a physiological role in the biosynthesis of ovarian steroid hormones or follicular maturation and fluid dynamics.

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