Figure 6.

The position of the tag affects the level of Act88F expression. Immunoblotting of IFM extracts from KM88 null mutants, from wild-type flies, and from tagged Act88F transformants with a monoclonal antibody that recognizes different actin isoforms reveals that the amounts of C-terminally tagged actin are significantly lower than the amounts of Act88F in wild-type (WT) flies. Act88F with an N-terminal tag is expressed at levels similar to endogenous Act88F in wild-type IFM. N-terminally tagged arthrin (∼55 kDa) is also detected by the anti-actin antibody. Consistent with the immunoblot shown in Figure 2, the antibody recognizes multiple 11-mer–tagged Act88F and arthrin bands. The band in the IFM extract of KM88 represents non-IFM actin isoforms.