Determination of a very precise region within myosin as the putative SF9 binding domain. Alignment of cDNA fragments within the ORF (thick black line) of the three non-muscle myosin heavy chains. 196 cDNA fragments of MYH9 (A), 55 of MYH10 (B) and 61 of MYH11 (C) were found in the screen, yielding SID of 35, 33 and 70 amino acids in length, respectively (depicted in red). B. Sequence alignment of the three myosin-homologue SID (boxed) determines a precise 29-amino-acid long putative binding domain. Note almost complete (>93%) amino acid sequence identity for the common SID (depicted in red).