Analysis of initiator methionine codon for Kozak composition and its influence on initiation of translation. Panel A. Comparison between the eukaryotic Kozak consensus sequence and the sequence surrounding the CD40L translation initiation site. Nucleotides critical for efficient translation initiation are highlighted. Nucleotide substitutions predicted to enhance CD40L translation initiation without modifying the coding region are shown in red. Panel B. Correlation between CD40L small isoform expression and IL-12 induction. Graph demonstrates quantitative assessment of level of IL-12 cytokine secretion and below are shown SDS PAGE analysis of translation products. WT: wile type CD40L RNA, +Kozak: CD40L sequence with optimized first methionine codon; -Me1: CD40L sequence with knock out of first naturally occurring initiator methionine codon.