Research

Overview

Symbiotic relationships can take different forms, including mutualism, commensalism, and parasitism (although these categories are not as discrete as they’re often considered to be!). I focus on parasites, and I’m broadly interested in the genetic basis of their detection and utilization of a host. Specifically, my research in genetics addresses the following three questions about how parasites interact with hosts:

  • How do parasites perceive hosts?
  • What determines host range and preference in parasites?
  • How can resistance to parasites be improved in susceptible host species?

I address these questions in parasitic plants from the Orobanchaceae and in American chestnut trees. Berry College sits on 27,000 acres, and several species of Orobanchaceae are found right here on campus! Professor Marty Cipollini has also established an impressive chestnut breeding program here, with multiple orchards on campus. In my research, I aim to engage undergraduates in field collection, laboratory experiments, and bioinformatics to address important questions about how parasites and hosts interact.

aureolaria_calvary_to_chimney_rock
Aureolaria is a genus of parasitic plants that can be found on the Berry College campus.

In the past, I’ve worked in animal, plant, and fungal systems in my doctoral training at the University of Georgia and my postdoctoral positions at Spelman College and Emory University.

Publications (* denotes Berry College student author):

Merrilles*, A.R., Buelow*, A.L., Early*, J.P., McCulla*, M.E., Williams*, S.J., Conn, C.E. The evolution of KAI2 and its homologue DLK2 in parasitic plants and their non-parasitic relatives. Biological Journal of the Linnean Society 147(1): blaf143.

Hollis*, M.M., Quigley*, S.L., Conn, C.E. (2024) The molecular evolution of the haustorium formation genes Pirin and QR1 in parasitic plants. Biological Journal of the Linnean Society 143(4): blae105.

Berasategui, A., Salem, H., Moller, A.G., Christopher, Y., Vidaurre Montoya, Q., Conn, C., Read, T.D., Rodrigues, A., Ziemert, N., Gerardo, N. (2024) Genomic insights into the evolution of secondary metabolism of Escovopsis and its allies, specialized fungal symbionts of fungus-farming ants. mSystems 9(7): e00576-24.

Conn, C.E., Howie, N., Lynch, M., Lee*, S., Young*, E., Westbrook, J.W., Holliday, J., Zhang, Q., Cipollini, M. (2023) Validation of an alternative small stem assay for blight resistance in backcross hybrid chestnuts (Castanea) and recommendations for its expanded use. Plant Disease. DOI 10.1094/PDIS-06-22-1489-RE.

Martinez, S.E., Conn, C.E., Guercio, A.M., Sepulveda, C., Fiscus, C.J., Koenig, D., Shabek, N., Nelson, D.C. (2022) A KARRIKIN INSENSITIVE2 paralog in lettuce mediates highly sensitive germination responses to karrikinolide. Plant Physiology 190(2): 1440 – 1456.

Yoshida, S., Kim, S., Wafula, E.K., Tanskanen, J., Kim, Y.-M., Honaas, L., Yang, Z., Spallek, T., Conn, C.E., Ichihashi, Y., Cheong, K., Cui, S., Der, J.P., Gundlach, H., Jiao, Y., Hori, C., Ishida, J.K., Kasahara, H., Kiba, T., Kim, M.-S., Koo, N., Laohavisit, A., Lee, Y.-H., Lumba, S., McCourt, P., Mortimer, J.C., Mutuku, J. M., Nomura, T., Sasaki-Sekimoto, Y., Seto, Y., Wang, Y., Wakatake, T., Sakakibara, H., Demura, T., Yamaguchi, S., Yoneyama, K., Manabe, R., Nelson, D.C., Schulman, A., Timko, M.P., DePamphilis, C.W., Choi, D., Shirasu, K. (2019) Genome sequence of Striga asiatica provides insight into the evolution of plant parasitism. Current Biology 29(18): 3041 – 3052. e4.

Conn, C.E., Nelson, D.C. (2017) It’s not easy being not green: the making of a parasitic plant. The Plant Cell 29(4): tpc.117.tt0417; DOI 10.1105/tpc.117.tt0417.

Lopez-Obando, M., Conn, C.E., Hoffmann, B., Bythell-Douglas, R., Nelson, D.C., Rameau, C., Bonhomme, S. (2016) Structural modeling and transcriptional responses highlight a clade of PpKAI2-LIKE genes as candidate receptors for strigolactones in Physcomitrella patens. Planta DOI 10.1007/s00425-016-2481-y.

Conn, C.E., Nelson, D.C. (2016) Evidence that KARRIKIN-INSENSITIVE2 (KAI2) receptors may perceive an unknown signal that is not karrikin or strigolactone. Frontiers in Plant Science 6:1219. DOI 10.3389/fpls.2015. 01219.

Conn, C.E., Bythell-Douglas, R., Neumann, D., Yoshida, S., Whittington, B., Westwood, J.H., Shirasu, K., Bond, C.S., Dyer, K.A., Nelson, D.C. (2015) Convergent evolution of strigolactone perception enabled host detection in parasitic plants. Science 349(6247): 540 – 543.

Hedges, S.B., Conn, C.E. (2012) A new skink fauna from Caribbean islands (Squamata, Mabuyidae, Mabuyinae). Zootaxa 3288: 1 – 244.

For more information, check out my Google Scholar profile.