Beginning within the nucleus, the first step leading to the synthesis of a polypeptide is _____. beginning within the nucleus, the first step leading to the synthesis of a polypeptide is _____. removal of introns from rna and the stitching together of exons transferring of information from dna to messenger rna translation of an rna nucleotide sequence into a sequence of amino acids linking of nucleotides to form a polypeptide translation of a dna nucleotide sequence into a sequence of amino acids