Mouse TMCO5 is localized to the manchette microtubules involved in vesicle transfer in the elongating spermatids

Abstract

As a result of a high-throughput in situ hybridization screening for adult mouse testes, we found that the mRNA for Tmco5 is expressed in round and elongating spermatids. Tmco5 belongs to the Tmco ( Transmembrane and coiled-coil domains ) gene family and has a coiled-coil domain in the N-terminal and a transmembrane domain in the C-terminal region. A monoclonal antibody raised against recombinant TMCO5 revealed that the protein is expressed exclusively in the elongating spermatids of step 9 to 12 and is localized to the manchette, a transiently emerging construction, which predominantly consists of cytoskeleton microtubules and actin filaments. This structure serves in the transport of Golgi-derived non-acrosomal vesicles. Moreover, induced expression of TMCO5 in CHO cells resulted in the co-localization of TMCO5 with β-tubulin besides the reorganization of the Golgi apparatus. Judging from the results and considering the domain structure of TMCO5, we assume that Tmco5 may have a role in vesicle transport along the manchette.

Forkhead-associated phosphopeptide binding domain 1 (FHAD1) deficiency impaired murine sperm motility

“…Previous studies in which testis-enriched genes were inactivated have successfully demonstrated the contributions of these genes to male infertility and the impairment of spermatogenesis in mice, underscoring their importance to reproductive outcomes. This approach has been used to evaluate many candidate testes-enriched genes to date, with many having been found to play detectable roles in the regulation of murine spermatogenesis ( Castaneda et al, 2017 ; Gao et al, 2020 ; Hua et al, 2019 ; Shah et al, 2021 ; Shibuya et al, 2015 ; Yamase et al, 2019 ; Yang et al, 2021 ; Zhang et al, 2019 ), whereas others are dispensable in this context, including FANK1 , Hspa1l , and Tex33 ( Wang et al, 2020 ; Zhang et al, 2019 ; Zhu et al, 2020 ). It has been suggested that the proteins encoded by these genes may have redundant functions in spermatogenesis.…”

Sperm Differentiation: The Role of Trafficking of Proteins

“…Further studies are needed to determine its interacting partners as well as the function this protein plays in the manchette. TMCO5A has been recently detected in the manchette [204]. However, its function in this organelle and the interacting proteins are still unknown.…”

“…However, its function in this organelle and the interacting proteins are still unknown. Because of localization in the Golgi, it has been suggested that TMCO5A may be involved in vesicle transport in the manchette [204], but this needs further experimental confirmations. As a whole, the proteins that failed to be incorporated into the interactome deserve further study in order to understand their roles in the manchette and to identify their interacting partners.…”