Transportin-3 (TNPO3)

Transportin-3 (TNPO3) is a nuclear import receptor belonging to the β-karyopherin family, responsible for shuttling serine/arginine-rich (SR) proteins—especially splicing regulators—into the nucleus[1][4]. It is essential for correct pre-mRNA splicing and regulates RNA metabolism in various cell types[1][2][3]. TNPO3 also acts as an important cellular cofactor for HIV-1, facilitating the nuclear import of viral components necessary for HIV-1 replication[1][3]. Mutations in the TNPO3 gene cause autosomal dominant limb girdle muscular dystrophy type 1F (LGMD1F), reflecting its critical role in muscle and possibly other tissues[2][3]. Because of its functions in viral infection and splicing regulation, it is a potential but challenging therapeutic target.

Other names

Importin-12IPO12Transportin-SRTRN-SRTRN-SR2Imp12MTR10ALGMD1FLGMDD2limb girdle muscular dystrophy 1F (autosomal dominant)

Drugs or molecular inhibitors would likely block TNPO3's cargo recognition or nuclear import function, thereby affecting splicing factor localization and, e.g., impairing HIV-1 cofactor functions[1][3]