Acta1^tm1Hrd

A C to T base pair substitution in exon 2 was introduced into the mouse alpha-skeletal actin (Acta1) genomic DNA sequence (construct spanning ~1.8 kbp upstream of exon 1 through the 3' UTR about 2.3 kbp downstream of exon 7) by site-directed mutagenesis. The CAC to TAC mutation of codon 40 results in a single amino acid substitution of histidine to tyrosine in the encoded protein. A loxP-flanked PGKneo cassette was also placed downstream of the 3' UTR. Both the human and mouse alpha-skeletal actin genes encode two N-terminal amino acids (Met and Cys) which are removed from the protein coincident with translation. Therefore, conventional numbering of the alpha-skeletal actin amino acid sequence begins with the third encoded amino acid (Asp). Hence, the H40Y mutation refers to the 40th amino acid in the protein (although this is amino acid 42 in the gene sequence). (J:184588)