D-Aspartate Upregulates DAAM1 Protein Levels in the Rat Testis and Induces Its Localization in Spermatogonia Nucleus

• Published in: Biomolecules (Basel, Switzerland) Switzerland), 2020-04, Vol.10 (5), p.677
• Main Authors: Venditti, Massimo, Santillo, Alessandra, Falvo, Sara, Fiore, Maria Maddalena Di, Baccari, Gabriella Chieffi, Minucci, Sergio
• Format: Article
• Language: English
• Subjects: Active Transport, Cell Nucleus; Animals; Aspartate; Cell Line; Cell Nucleus - metabolism; Cells, Cultured; Cytoskeletal Proteins - chemistry; Cytoskeletal Proteins - genetics; Cytoskeletal Proteins - metabolism; cytoskeleton; D-Asp; D-Aspartic Acid - metabolism; D-Aspartic Acid - pharmacology; DAAM1; formins; Genetic aspects; Genetic regulation; Male; nuclear actin; Nuclear Localization Signals; Observations; Physiological aspects; Rats; Rats, Wistar; Spermatogenesis; Spermatogonia - drug effects; Spermatogonia - metabolism; Testis; Testis - cytology; Testis - metabolism; Up-Regulation
• ISSN: 2218-273X; 2218-273X
• DOI: 10.3390/biom10050677

Cell differentiation during spermatogenesis requires a proper actin dynamic, regulated by several proteins, including formins. Disheveled-Associated-Activator of Morphogenesis1 (DAAM1) belongs to the formins and promotes actin polymerization. Our results showed that oral D-Aspartate (D-Asp) administration, an excitatory amino acid, increased DAAM1 protein levels in germ cells cytoplasm of rat testis. Interestingly, after the treatment, DAAM1 also localized in rat spermatogonia (SPG) and mouse GC-1 cells nuclei. We provided bioinformatic evidence that DAAM1 sequence has two predicted NLS, supporting its nuclear localization. The data also suggested a role of D-Asp in promoting DAAM1 shuttling to the nuclear compartment of those proliferative cells. In addition, the proliferative action induced by D-Asp is confirmed by the increased levels of PCNA, a protein expressed in the nucleus of cells in the S phase and p-H3, a histone crucial for chromatin condensation during mitosis and meiosis. In conclusion, we demonstrated, for the first time, an increased DAAM1 protein levels following D-Asp treatment in rat testis and also its localization in the nucleus of rat SPG and in mouse GC-1 cells. Our results suggest an assumed role for this formin as a regulator of actin dynamics in both cytoplasm and nuclei of the germ cells.