Cystathionine β‐synthase is required for oocyte quality by ensuring proper meiotic spindle assembly

• Published in: Cell proliferation Vol. 55; no. 12; pp. e13322 - n/a
• Main Authors: Cao, Yan, Zhu, Xinyu, Zhen, Panpan, Tian, Ying, Ji, Dengyu, Xue, Ke, Yan, Wenjing, Chai, Jiayin, Liu, Huirong, Wang, Wen
• Format: Journal Article
• Language: English
• Published: Chichester John Wiley & Sons, Inc 01.12.2022
• Subjects: Acetylation; Antibodies; Assembly; Biotechnology; Chromosomes; Cloning; Depletion; Experiments; Fertilization; Follicles; Gametocytes; Homocysteine; Human subjects; Immunofluorescence; Immunohistochemistry; Infertility; Maturation; Meiosis; Metaphase; Microinjection; Microtubules; Misalignment; Nocodazole; Oocytes; Ovaries; Paclitaxel; Tubulin; Variance analysis
• ISSN: 0960-7722; 1365-2184; 1365-2184
• DOI: 10.1111/cpr.13322

Objectives Poor oocyte quality is detrimental to fertilization and embryo development, which causes infertility. Cystathionine β‐synthase (CBS) is one of the key enzymes modulating the metabolism of homocysteine (Hcy). Studies have shown that CBS plays an important role in female reproduction. However, the role of CBS in regulating oocyte quality during meiotic maturation still needs further investigation. Materials and Methods Immunohistochemistry, immunofluorescence, drug treatment, western blot, cRNA construct and in vitro transcription, microinjection of morpholino oligo and cRNA were performed for this study. Results We found that CBS was expressed both in human and mouse oocytes of follicles. In mouse oocytes, CBS was distributed in the nucleus at germinal vesicle (GV) stage and localized to spindle from germinal vesicle breakdown (GVBD) to metaphase II (MII). The expression of CBS was reduced in ovaries and oocytes of aged mice. CBS depletion resulted in meiotic arrest, spindle abnormality and chromosome misalignment, disrupted kinetochore‐microtubule attachments and provoked spindle assembly checkpoint (SAC). CBS was disassembled when microtubules were disrupted with nocodazole, and co‐localized with the stabilized microtubules after taxol treatment. Furthermore, CBS depletion decreased the acetylation of α‐tubulin. Conclusions These results reveal that CBS is required for the acetylation of α‐tubulin to ensure proper spindle assembly in regulating oocyte quality during meiotic maturation. CBS is required for oocyte quality by ensuring proper spindle assembly. During oocyte meiotic maturation, CBS ensures spindle assembly by participating in the acetylation of α‐tubulin to stabilize microtubules. Kinetochores remain attached by spindle microtubules. SAC is removed from the kinetochores and then the chromosomes can be separated correctly.