NIMA-related kinase 2 (NEK2) is a serine/threonine kinase that plays crucial roles in cellular events such as centrosome separation, cell cycle progression, spindle assembly checkpoint (SAC) regulation, and microtubule stabilization. However, its regulatory function during oocyte meiotic maturation remains unclear. In this study, NEK2 activity was inhibited using the specific inhibitor MBM-55 to evaluate its role in oocyte meiotic maturation and early embryonic development. NEK2 depletion impaired multiple indicators associated with oocyte maturation and decreased the maturation rate. Mechanistic analysis suggested that NEK2 inhibition altered spindle organization and chromosome alignment, which may be associated with impaired kinetochore-microtubule (K-MT) interactions and altered SAC-associated signaling, collectively contributing to MI-stage arrest and increased aneuploidy. In addition, NEK2 deficiency impaired the actin network, reducing spindle migration, preventing the efficient repair of accumulated DNA damage and ultimately leading to apoptosis. NEK2 inhibition in oocytes reduced subsequent embryonic developmental competence, leading to a lower blastocyst formation rate. These findings demonstrate that NEK2 is a critical regulator of porcine oocyte meiotic maturation through its roles in SAC regulation, K-MT attachment, cytoskeletal dynamics, and the DNA damage response.
Se‑Been Jeon, Pil-Soo Jeong, Hyo‑Gu Kang et al.· Molecular and Cellular Bioch...· 0 citations
Abstract RNA-guided obligate mobile element guided activity systems derived from transposable elements have emerged as compact genome-editing tools that may replace clustered regularly interspaced short palindromic repeats platforms. We established a dual-mode genome regulation platform using ISDge10 TnpB effectors and engineered ωRNAs, in which modulation of the ωRNA guide length enables switching between programmable transcriptional activation and genome editing. TnpB programmed with a 10-nt guide region of the ωRNA engages target DNA without inducing double-strand breaks. Fusion of transcriptional activators with Sso7d (DNA-binding protein from Sulfolobus solfataricus) enables specific transcriptional upregulation across endogenous loci. Restoring the ωRNA guide length to 20 nt triggers DNA cleavage, thereby supporting homology-directed repair-mediated sequence correction. A catalytically inactivated TnpB-based adenine base editor enabled A-to-G base conversion at genomic targets. TnpB shows strict ωRNA-dependent mismatch sensitivity with low off-target effects, suggesting its potential as a high-fidelity genome regulation platform. Compact ISDge10 TnpB facilitates co-packaging of effector and ωRNA in a single adeno-associated virus vector and co-expression of large functional domains. Thus, this study expands RNA-guided genome-editing capabilities.
Yeounsun Oh, Se‑Been Jeon, Lee Wha Gwon et al.· Nucleic Acids Research· 0 citations
