Analysis of manchette-associated TMCO5A involved in spermiogenesis

2018 Fiscal Year Final Research Report

• Project/Area Number: 15K07128
• Research Category: Grant-in-Aid for Scientific Research (C)
• Allocation Type: Multi-year Fund
• Section: 一般
• Research Field: Morphology/Structure
• Research Institution: Kyushu University
• Principal Investigator: IIDA HIROSHI 九州大学, 農学研究院, 教授 (70150399)
• Project Period (FY): 2015-04-01 – 2019-03-31
• Keywords: 精子形成 / 発生・分化、 / 細胞組織、 / 生体分子 / 微小管 / マンチェッタ

Outline of Final Research Achievements

We isolated Tmco5A gene using PCR-based subtraction technique. When expressed in COS7 cells, TMCO5A was distributed to endoplasmic reticulum-nuclear membrane (ER-NM) as a membrane-associated protein in the cells, while TMCO5A△C lacking the transmembrane region (TM) mislocalized and diffused throughout the cytoplasm. Double immunolabeling of isolated spermatids with the anti-TMCO5A and the anti-βtubulin antibodies showed that TMCO5A was always in close association with developing manchette microtubules, but not completely co-localized with them. On the other hand, we found that almost all TMCO5A was co-localized with SUN4, a LINC (Linker of nucleoskeleton and cytoskeleton) complex protein at the posterior part of nuclei in spermatids. These data suggested that TMCO5A is more closely located to the nuclei than manchette microtubules. It is likely that TMCO5A is involved in the process of spermiogenesis in which manchette microtubules are required.

Free Research Field

動物発生学

Academic Significance and Societal Importance of the Research Achievements

本研究成果に記載したTMCO5Aは、我々の研究室において発見された新規の尾鞘構成分子である。尾鞘の生理的機能や形成・分解メカニズムはいまだ不明の点が多く、TMCO5A分子の局在、動態、機能解析によって、精子形成における尾鞘の機能の一端が明らかにされ、精子形成機構の研究に新たな展開をもたらすことが期待できる。