KPNA6

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Description

The KPNA6 (karyopherin subunit alpha 6) is a protein-coding gene located on chromosome 1.

Importin subunit alpha-7 is a protein encoded by the KPNA6 gene in humans. It is involved in nucleocytoplasmic transport, a process that moves proteins across the nuclear envelope through nuclear pore complexes. This transport requires the NLS import receptor, a heterodimer of importin alpha and beta subunits, also known as karyopherins. Importin alpha binds to the NLS-containing cargo in the cytoplasm, and importin beta docks the complex at the cytoplasmic side of the nuclear pore complex. In the presence of nucleoside triphosphates and the small GTP binding protein Ran, the complex moves into the nuclear pore complex, and the importin subunits dissociate. Importin alpha enters the nucleoplasm with its passenger protein, while importin beta remains at the pore. Importin alpha-7 is a member of the importin alpha family.

KPNA6, also known as importin subunit alpha-7, plays a crucial role in nuclear protein import. It acts as an adapter protein for the nuclear receptor KPNB1, directly binding to substrates containing specific nuclear localization signals (NLS). This binding facilitates the docking of the importin/substrate complex to the nuclear pore complex (NPC) via KPNB1's interaction with nucleoporin FxFG repeats. Subsequently, the complex translocates through the NPC in an energy-dependent, Ran-mediated process. Once inside the nucleus, Ran binds to importin-beta, leading to the separation of the complex. Importin-alpha and -beta are then re-exported to the cytoplasm, where GTP hydrolysis releases Ran from importin. The directional transport of proteins into the nucleus is regulated by the asymmetric distribution of Ran in its GTP- and GDP-bound forms between the cytoplasm and nucleus.

KPNA6 is also known as IPOA7.

Associated Diseases

• female infertility due to oocyte meiotic arrest
• female infertility due to zona pellucida defect
• spermatogenic failure 8
• male infertility with teratozoospermia due to single gene mutation
• partial chromosome Y deletion
• spermatogenic failure 1
• spermatogenic failure 48
• spermatogenic failure 22
• spermatogenic failure 25
• spermatogenic failure 51
• spermatogenic failure, X-linked, 3
• spermatogenic failure 40
• Gollop-Wolfgang complex
• spermatogenic failure 47
• premature ovarian failure 19
• oocyte maturation defect 9
• spermatogenic failure 39
• spermatogenic failure 65
• spermatogenic failure 11
• spermatogenic failure 10