Germline cysts are clusters of germ cells that arise by division from a single cell and are connected to one another by stable intercellular bridges. Cysts are a highly conserved stage of pre-meiotic germ cell development, but the molecular mechanisms that control their formation are highly unknown. Developing cysts in Drosophila contain a cytoplasmic organelle called a fusome, which plays a critical role in cyst formation. The SCAR gene, which encodes an actin regulatory protein, was identified in a screen for mutations that disrupt fusomes and cyst formation. It was not clear, however, if the mutation l(2)k03107 disrupts only SCAR. To address this question, new alleles were created by excising the P-element in l(2)k03107. These alleles were then characterized molecularly and phenotypically. The results show that two alleles have deletions in the SCAR gene. Further testing must be done to determine the role of SCAR in cyst formation.
