Volume 226, Issue 2, February 2024

Drosophila genetics was instrumental in defining the BMP signaling pathway. In this FlyBook chapter, Akiyama, Raftery, and Wharton provide a historical account of the role that Drosophila research—especially genetic modifier screens—played in deciphering elements of BMP signaling and identifying its many functions. They cover more recent studies which demonstrate that the versatility of BMP signaling as a potent intercellular communication pathway lies in the diverse regulatory mechanisms that are critical to controlling signaling activity.

Schwartz et al. develop the entomopathogenic nematode (EPN) Steinernema hermaphroditum as a versatile system for the molecular genetic exploration of symbiosis, pathogenesis, and other biological questions. They report the first molecular identification of an EPN gene on the basis of its mutant phenotype and confirm it using CRISPR-Cas9 genome editing to target the identified gene. The reported tools will allow researchers to explore the biology of related EPNs used to control agricultural pests.

To fully understand the biology of an organism, one must know the function of all its genes. In Drosophila melanogaster, most genes on the 4th chromosome have been ignored. Among its 79 protein coding genes, only 42% have a mutant phenotype, while 94% have human homologs. Here, Stinchfield et al. report the Fourth Chromosome Resource Project, a collection of 445+ strains that provides the ability, previously unavailable, to study genes or mutations on the 4th.