In a direct sense, no. PGP signatures and Bitcoin use different cryptographic algorithms. Bitcoin uses ECDSA (Elliptic Curve Digital Signature Algorithm) for its key pairs, while PGP typically uses RSA or DSA.

However, you could theoretically use a PGP signature to sign a message proving your identity outside the Bitcoin network - similar to how you can sign messages with your Bitcoin private key.

But remember: Don't go mixing up your keys! Your PGP keys aren't going to help you make transactions in the world of bitcoin.