Integrated analysis of proteomics and metabolomics reveals the potential sex determination mechanism in Odontobutis potamophila

DNALI1 interacts with the MEIG1/PACRG complex within the manchette and is required for proper sperm flagellum assembly in mice

The manchette is a transient and unique structure present in elongating spermatids and required for proper differentiation of the germ cells during spermatogenesis. Previous work indicated that the MEIG1/PACRG complex locates in the manchette and is involved in the transport of cargos, such as SPAG16L, to build the sperm flagellum. Here, using co-immunoprecipitation and pull-down approaches in various cell systems, we established that DNALI1, an axonemal component originally cloned from Chlamydomonas reinhardtii, recruits and stabilizes PACRG and we confirm in vivo, the co-localization of DNALI1 and PACRG in the manchette by immunofluorescence of elongating murine spermatids. We next generated mice with a specific deficiency of DNALI1 in male germ cells, and observed a dramatic reduction of the sperm cells, which results in male infertility. In addition, we observed that the majority of the sperm cells exhibited abnormal morphology including misshapen heads, bent tails, enlarged midpiece, discontinuous accessory structure, emphasizing the importance of DNALI1 in sperm differentiation. Examination of testis histology confirmed impaired spermiogenesis in the mutant mice. Importantly, while testicular levels of MEIG1, PACRG, and SPAG16L proteins were unchanged in the Dnali1 mutant mice, their localization within the manchette was greatly affected, indicating that DNALI1 is required for the formation of the MEIG1/PACRG complex within the manchette. Interestingly, in contrast to MEIG1 and PACRG-deficient mice, the DNALI1-deficient mice also showed impaired sperm spermiation/individualization, suggesting additional functions beyond its involvement in the manchette structure. Overall, our work identifies DNALI1 as a protein required for sperm development.

A Chromosome-Level Genome Assembly of the Dark Sleeper Odontobutis potamophila

The dark sleeper, Odontobutis potamophila, is a commercially valuable fish that widely distributed in China and Southeast Asia countries. The phenomenon of sexual dimorphism in growth is conspicuous, which the males grow substantially larger and faster than the females. However, the high-quality genome resources for gaining insight into sex-determining mechanisms to develop sex-control breeding are still lacking. Here, a chromosomal-level genome assembly of O. potamophila was generated from a combination of Illumina reads, 10× Genomics sequencing, and Hi-C chromatin interaction sequencing. The assembled genome was 1,134.62 Mb with a contig N50 of 22.25 Mb and a scaffold N50 of 24.85 Mb, representing 94.4% completeness (Benchmarking Universal Single-Copy Orthologs). Using Hi-C data, 96.49% of the total contig bases were anchored to the 22 chromosomes, with a contig N50 of 22.25 Mb and a scaffold N50 of 47.68 Mb. Approximately 54.18% of the genome were identified as repetitive elements, and 23,923 protein-coding genes were annotated in the genome. The assembled genome can be used as a valuable resource for molecular breeding and functional studies of O. potamophila in the future.

Copper nanoparticles induce the formation of fatty liver in Takifugu fasciatus triggered by the PERK-EIF2α- SREBP-1c pathway

Copper nanoparticles (CuNPs), a new pollutant in water environments, were widely used in various industrial and commercial applications. This study indicated that the presence of CuNPs exposure under environmental related concentration is an inducing factor that contributes to the fatty liver formation in Takifugu fasciatus. Furthermore, we explored the fatty liver formation mechanism. The results shown, (1) the cloned genes related to endoplasmic reticulum stress (ERS) (GRP78, IRE-1α, PERK, and ATF-6α) were highly expressed in the liver of T. fasciatus. (2) after 30-days exposure, CuNPs accumulated in the endoplasmic reticulum of liver and induced the appearance of ERS, then activated unfolded protein response (UPR) signaling pathway. Furthermore, the SREBP-1c pathway that plays a key role in lipid synthesis was activated. (3) by using 4-PBA and GSK inhibitors to respectively stimulate ERS and PKR-like ER kinase (PERK) through in vitro experiments, we confirmed that CuNPs induced the fatty liver formation in T. fasciatus triggered by the PERK-EIF2α pathway by activating the SREBP-1c pathway to promote fatty liver formation. This study provides a new perspective for identifying the pathogens of fatty liver formation, and adds to the knowledge of the ecological safety data service of CuNPs in water.