Amino acid replacement: S31A.
A His3.3A transgene with an S31A amino acid substitution carrying two N-terminally-located Tag:FLAG epitopes.
His3.3A2X1, His3.3AS31A.Tag:FLAG, His3.3B0 has viable phenotype
His3.3A2X1, His3.3AS31A.Tag:FLAG, His3.3B0 has male fertile phenotype
His3.3A2X1, His3.3B0 double mutant males also carrying a His3.3AS31A.T:Zzzz\FLAG transgene are viable and fertile.