Work being done on the Nos. 2, 4 and 5 subway lines has many Bronx straphangers feeling frustrated.

The Metropolitan Transportation Authority has stopped express subway service on the No. 5 line between the 149th Street and 180th Street stations. During the afternoon rush hour, commuters on the No. 5 trains must transfer to the No. 2 line.

Transit officials say the work is part of a necessary $280-million modernization project.