Research Summary

My laboratory is investigating the genetic control of key developmental events, using Drosophila melanogaster as our organism. Our approach has been to identify genetically as many of the components of the process as possible, attempt to order these elements through genetic interactions, and then move to a molecular analysis of the central genes in the process. Since becoming Emeritus, I have concentrated on a set of mutations that affect the mitochondrial derivative during spermiogenesis. In wild-type flies all the mitochondria in each spermatid fuse into two mitochondria which interweave with each other in the Nebenkern. During growth of the axoneme the two mitochondria unwind from each other and extend along the growing axoneme. Mutations which interfere with either the fusion process or the extension process are sterile. Efforts are in progress to identify the molecular processes involved in more than 25 different mutations affecting these events. I also continue a collaboration with Dr. Yuzo Niki in Japan to develop protocols for the culture of ovarian germline stem cells. We have shown that cultured cells can repopulate the germline and produce functional eggs. We currently have stable cultures composed of mixed populations of somatic and germline cells. If gene replacement methods can be developed for germline cells in these cultures, these cells could be the source for genetically modified germlines in flies.

Selected Publications

Yamashita, Y. M., Mahowald, A. P., Perlin, J. R., and Fuller, M. T. 2007. Asymmetric inheritance of mother versus daughter centrosome in stem cell division. Science 315:518-21. (PubMed)

Niki, Y., Yamaguchi, T., and Mahowald, A. P. 2006. Establishment of stable cell lines of Drosophila germline stem cells. Proc. Natl. Acad. Sci. USA 103: 16325-16330. (PubMed)

Tazuke, S. I., C. Schulz, L. Gilboa, A. P. Mahowald, A. Guichet, A. Ephrussi, C. G. Wood, R. Lehmann and M. T. Fuller. 2002. A germ line specfic gap junction protein is required for survival of differentiating early germ cells. Development 129: 2529-2539. (PubMed)

Niki, Y. and Mahowald, A. P. (2003). "Ovarian cystocytes can repopulate the embryonic germ line and produce functional gametes." Proc Natl Acad Sci U S A 100: 14042-5. (PubMed)

Mahowald, A. P. (2001). "Assembly of the Drosophila germ plasm." Int Rev Cytol 203: 187-213. (PubMed)