A eukaryotic gene contains 5 exons and 4 introns. Each exon has a length of 180 base pairs (bp), and each intron has a length of 600 bp. This gene is transcribed into pre-mRNA, spliced to form mature mRNA, and then translated into a polypeptide.

Assuming that translation begins at the first nucleotide of the mature mRNA and terminates at the final codon, which acts as a stop codon, what is the length of the resulting polypeptide in amino acids?