Lin28A

LIN28A, also known as LIN28, is a conserved RNA-binding protein found in a variety of organisms, including humans, mice, and worms. It plays a crucial role in regulating developmental timing and the transition from embryonic to adult stem cell states. LIN28A is characterized by its N-terminal cold-shock domain and its C-terminal intrinsically disordered region.

In mammals, LIN28A is highly expressed in embryonic stem cells and germ cells, where it acts as a gatekeeper for pluripotency and development. One of its primary functions is to inhibit the maturation of microRNAs (miRNAs), particularly the let-7 family. By binding to precursor let-7 miRNAs, LIN28A prevents their processing by the Dicer enzyme, thereby maintaining high levels of pluripotency factors and suppressing differentiation. When LIN28A levels decrease, let-7 miRNA maturation is restored, leading to the suppression of pluripotency factors and promoting cell differentiation.

LIN28A is also involved in metabolic regulation and is implicated in cancer. Its expression is often elevated in various cancers, and it has been linked to tumor growth, metastasis, and resistance to chemotherapy. Research into LIN28A continues to explore its multifaceted roles in development, regeneration, and disease, making it a significant target for therapeutic interventions.