Let us consider $E$ an encryption algorithm that encrypts a message $m$ into a ciphertext $c$ using a key $K_e$. i.e $c = E(K_e, m)$. Similarly, decryption is achieved by $m = D(K_d, c)$.
Is there any public key encryption scheme where the encryption process is the same as the decryption process (i.e. $E=D$ )?