Fscn3, also known as testis fascin, is a testis-specific actin-bundling protein belonging to the fascin family of actin-bundling proteins [4,5]. It is specifically expressed in elongated spermatids and may be involved in microfilament rearrangements during spermatid head elongation and fertilization [4].

A study generating Fscn3 knockout mice through Nuclease technology technology showed that Fscn3-/-mice had normal testis morphology, testis to bodyweight ratio, sperm concentrations, sperm swimming velocity, and sperm morphology. These mice were also completely fertile, indicating that Fscn3 is dispensable for mouse spermatogenesis [1]. Bioinformatics analysis identified Fscn3 as a hub gene associated with spermatogenesis, and its down-regulation was observed in testicular germ cell tumors [2]. Additionally, a multi-trait exome-wide association study suggested that Fscn3 may impact back pain through loss-of-function variants [3].

In summary, although Fscn3 is a testis-specific actin-bundling protein, it is not essential for mouse spermatogenesis. The study of Fscn3 knockout mice has provided important insights into its non-essential role in spermatogenesis. The identification of its potential role in back pain through loss-of-function variants offers new directions for back pain research [1,3].

References:

1. Ali, Haider, Unar, Ahsanullah, Dil, Sobia, Khan, Ihsan, Shi, Qinghua. 2022. Testis-specific fascin component FSCN3 is dispensable for mouse spermatogenesis and fertility. In Molecular biology reports, 49, 6261-6268. doi:10.1007/s11033-022-07429-7. https://pubmed.ncbi.nlm.nih.gov/35449315/

2. Liu, Shuang, Bian, Yan-Chao, Wang, Wan-Lun, Xiao, Rui, Zhang, Chuan-Ling. 2023. Identification of hub genes associated with spermatogenesis by bioinformatics analysis. In Scientific reports, 13, 18435. doi:10.1038/s41598-023-45620-3. https://pubmed.ncbi.nlm.nih.gov/37891374/

3. Zorkoltseva, Irina V, Elgaeva, Elizaveta E, Belonogova, Nadezhda M, Tsepilov, Yakov A, Axenovich, Tatiana I. 2023. Multi-Trait Exome-Wide Association Study of Back Pain-Related Phenotypes. In Genes, 14, . doi:10.3390/genes14101962. https://pubmed.ncbi.nlm.nih.gov/37895311/

4. Tubb, Benjamin, Mulholland, David J, Vogl, Wayne, Cooney, Austin, Bryan, Joseph. . Testis fascin (FSCN3): a novel paralog of the actin-bundling protein fascin expressed specifically in the elongate spermatid head. In Experimental cell research, 275, 92-109. doi:. https://pubmed.ncbi.nlm.nih.gov/11925108/

5. Kollers, S, Day, A, Rocha, D. . Characterization of the porcine FSCN3 gene: cDNA cloning, genomic structure, mapping and polymorphisms. In Cytogenetic and genome research, 115, 189-92. doi:. https://pubmed.ncbi.nlm.nih.gov/17065803/