Meeting Abstract

P1.58  Tuesday, Jan. 4  The role of BTB proteins Abrupt and Bric-a-brac in the establishment of tarsal segmentation and larval leg regeneration in the flour beetle, Tribolium castaneum. SZE, C.C.**; SUZUKI, Y.; Wellesley College; Wellesley College ysuzuki@wellesley.edu

Metamorphosis is a life history strategy that involves dramatic reorganization of a juvenile to form a complex adult body. Complete metamorphosis, or holometaboly, in insects is characterized by the formation of the pupa and the dramatic transformation of larval appendages to adult appendages. Here, the functions of two Bric-a-brac Tramtrack Broad complex (BTB) proteins, Abrupt (Ab) and Bric-a-brac (Bab), were analyzed through RNA interference in order to ascertain their functions during metamorphosis in the flour beetle, Tribolium castaneum. Removal of Abrupt resulted in shortening of wings and reduced number of appendage segments, indicating a crucial role of Abrupt in coordinating adult appendage segmentation patterning. Similarly, knockdown of bab expression resulted in the reduction of tarsal segment number, indicating that bab regulates tarsal segmentation during larval-to-adult transformation. To determine whether these genes were required for larval leg regeneration, the effect of removal of ab, bab and spineless (ss) expression during larval leg regeneration was examined. Interestingly, the removal of ab, but not bab or ss, completely prevented ablated larval legs from regenerating after blastema formation, and the resulting adults lacked legs. Thus, ab may be an important regulator of limb regeneration.