A coordinate display maps the transcript from Gene Rysa as follows: E1: positions 1-6, exon, sequence UUGUUU; I1: positions 7-15, intron, sequence gugcagcag; E2: positions 16-21, exon, sequence AAACUC; I2: positions 22-29, intron, sequence gucuauag; E3: positions 30-35, exon, sequence UGGGUC; I3: positions 36-44, intron, sequence guuagacag; E4: positions 45-50, exon, sequence CUAGCG. Which mature mRNA sequence matches normal splicing, ignoring the cap and poly(A) tail?