From blood vessels to the small intestine to the spinal cord, tubes are an essential part of nearly all living organisms. The study of the formation of biological tubes, called tubulogenesis, is therefore indispensible in the understanding of the developmental pathways that, when impaired, cause many of the birth defects that afflict infants today. Our lab uses the fruit fly Drosophila melanogaster as a model organism to study these complex pathways. Recently, we discovered that a family of genes known as Imaginal Disc Growth Factors (IDGFs) are linked to tubulogenesis in fruit flies. However, the mechanisms by which these genes act, and their involvement in the tubulogenesis pathway, remain unclear. My project investigates the function of a specific IDGF, the gene CG5210, using a powerful new method for deleting genes known as the CRISPR/Cas9 system. With this technique, I created flies lacking the CG5210 gene by first designing highly specific plasmid vectors, which encoded RNAs that bound to the target DNA. When injected into fly embryos, these RNAs directed the Cas9 protein to cleave the DNA on either side of CG5210. Cas9 then replaced the gene with DNA that encodes a red fluorescent protein expressed in the eyes of the fly. The fluorescent red eyes served as a marker for a successful deletion in my later experiments. If my initial hypothesis is correct, I expect to see unusual phenotypes in these mutant flies that correlate with tube formation or growth pathways. From there, the next phase of my research will include further exploration of this genetic pathway, including determining what other genes and pathways interact with CG5210 to cause similar mutant phenotypes. This information will be an important contribution to our understanding of tubulogenesis and provide new insight into disease pathways that cause defects such as spina bifida in newborns.