Dr. April Hill
Professor of Biology
Clarence E. Denoon Professor of Science
Profile
We use marine and freshwater sponges as model systems to ask questions about the genetics and development of animal evolution and symbioses. Sponges are ancient animals that retain characteristics of an early experiment in multicellularity while also sharing some highly conserved features with other metazoans; these unique features provide a system in which to explore hypotheses about the evolution of animals. Research in our lab focuses the role of conserved developmental control genes and gene networks that originated prior to advent of animal adaptations such as tissues and nervous systems. We also work on elucidating the genetic pathways involved in the evolution of animal symbioses and their role in sponge development. Finally, our lab is involved in an international collaboration working on The Porifera Tree of Life (PorToL) project, which will generate a well-supported molecular and morphological phylogeny of the sponges that will improve our understanding of early animal evolution.
Grants and Fellowships
Vision and Change Leadership Fellow (2012-2013) - Partnership for Undergraduate Life Sciences Education (PULSE). PULSE is a joint effort by National Science Foundation (NSF), National Institutes of Health/NIGMS (NIH/NIGMS) and Howard Hughes Medical Institute (HHMI) to stimulate systemic changes within biology departments at all types of post-secondary educational institutions, based upon the findings from the 2011 report Vision and Change in Undergraduate Biology Education: A Call to Action.
Deutsches Elektronen-Synchrotron (German Electron Synchrotron; DESY) for use of new high brilliance 3rd Generation Synchrotron Radiation Source -Petra III. 2012 “Integrative functional genetic study of developmental genes in early evolved multicellular animals.” (Co-PI with Dr. Jörg U. Hammel, Germany).
National Science Foundation, DEB Assembling the Tree of Life 2008-2013 “Collaborative Research: AToL: PorToL – The Porifera Tree of Life.”
Thomas F. and Kate Miller Jeffress Memorial Trust, 2007, 2008-11. “Development of a ‘Model Sponge System’ to Study the Evolution of Early Animal Body Plans and Sensory Systems.”
National Science Foundation, OCE, 2007-2011 “RUI: Stability and structure of temperate and tropical marine sponge symbiont communities in response to climate change.”
Awards
Endowed Chair. Clarence E. Denoon Jr., Professorship of Science. 2009-2015
University of Richmond, Distinguished Educator Award, August 2008
Coston Family Fellow in Molecular Biology, University of Richmond, 2004-2009
Presentations

Society for Integrative and Comparative Biology. January 2013 (San Francisco, CA) “The freshwater sponge, Ephydatia muelleri, as a model to study the evolution of developmental regulatory programs.” A. Hill, A. Rivera, I. Winters*, A. Rued*, S. Ding*, D. Posfai*, L. Gentile, E. Webb*, W. Trok*.

Society for Integrative and Comparative Biology. January 2013 (San Francisco, CA) “Evolutionary and ecological significance of sponge-Symbiodinium symbioses: genetic regulation of uptake and maintenance in sponges.” M. Hill, A. Hill, C. Cotman*, S. Friday*, T. Heist,* M. McCauley*, K. Peterson*, C. Richardson*, A. Riesgo, B. Strehlow*.
Beckman Scholars Conference. August, 2012 (Irvine, CA) “Knockdown of PaxB and Six1/2 by RNAi leads to defects of the aquiferous system in the freshwater sponge, Ephydatia muelleri” I. Winters* and A. Hill.
12th International Coral Reef Symposium. July 2012 (Cairns, Australia) “Genetic regulation of zooxanthella uptake and maintenance in sponges.” M. Hill, B. Strehlow*, C. Richardson*, K. Peterson*, C. Cotman*, M. McCauley*, S. Friday*, T. Heist*, A. Riesgo, and A. Hill.
Society for the Study of Evolution, Evolution Meeting. July 2012 (Ottawa, Canada) “Reconstruction of family-level phylogenetic relationships within Demospongiae (Porifera) using nuclear encoded housekeeping genes.” M. Hill, A. Hill, J. Lopez, and 30 others of PorToL consortium including five UR undergraduates (presented by J. Lopez).
Second Sponge Sister Species International Genome Workshop, May 2012 (Split, Croatia) for PI lab groups to work on genome annotation and present findings related to the project. With I. Winters* and D. Pohlmann*.
Society for Integrative and Comparative Biology. January 2012 (Charleston, SC) “Examination of genetic regulation of Symbiodinium uptake and the morphological development of the zooxanthella-dense pinadocerm in the sponge Cliona varians.”  B. Strehlow*, M. McCauley*, C. Richardson*, K. Peterson*, C. Cotman*, A. Hill, and M. Hill.
Society for Integrative and Comparative Biology. January 2012 (Charleston, SC) “Knockdown of PaxB and Six1/2 by RNAi leads to developmental defects of the aquiferous system in the freshwater sponge Ephydatia muelleri.” I. Winters*, A. Rued*, S. Ding*, D. Posfai*, A. Rivera, L. Gentile, and A. Hill.
Society for Integrative and Comparative Biology. January 2012 (Charleston, SC) “Nuclear 28S ribosomal subunit gene sequences support new relationships among families and orders of Porifera.” C. Carmack, N. Redmond, D. Pohlmann*, L. Spicer, R.W. Thacker, L. Colin, M. Hill, A. Hill, J. Lopez, M.C. Diaz, S. Pomponi, P. Bangalore.
Society for Integrative and Comparative Biology. Annual Meeting. January 2011 (Salt Lake City, Utah) “Origins of the Pax/Six gene regulatory network.” S. Ding*, D. Sassoon*, A. Rued*, E. Webb*, A. Hill, A. Rivera.
VII World Sponge Conference. Ancient Animals, New Challenges. September 2010 (Girona, Spain) “Evolution of Gene Regulatory Networks: Early construction of the Pax/Six regulatory hierarchy in sponges.” A. Hill, A. Rivera, B. Cieniewicz*, E. Danka*, S. Ding* A. Rued*, I. Winters*,  L. Gentile.
Society for Integrative and Comparative Biology. Annual Meeting January 2010 (Seattle, WA) “Evolution of Gene Regulatory Networks: Pax/Six in Ephydatia muelleri.” A. Rivera, B. Cieniewicz*, E. Danka*, I. Winters*, A. Rued*, L. Warner*, M. Hill and A. Hill.
Annual Biomedical Research Conference for Minority Students. November 2009 (Phoenix, AZ) “Sponge-associated bacterial communities change in response to antibiotic selection in a sponge stem cell aggregate system: Implications for enriching minority bacterial species.” C. Richardson*, M. Hill, L. Runyen-Janecky, A. Hill.
American Society for Microbiology. 109th General Meeting. May 2009 (Philadelphia, PA). “Sponge-associated bacterial communities change in response to antibiotic selection in a sponge stem cell aggregate system: Implications for enriching minority bacterial species.” C. Richardson*, M. Hill, L. Runyen-Janecky, A. Hill.
Society for Developmental Biology Northwest Regional Meeting. March 2009 (Friday Harbor Labs, University of Washington) “Evolution of T-boxes and the origins of gastrulation in a sponge-like ancestor.” P. Windsor, K. Holstien*, S.P. Leys, and A. Hill.
Benthic Ecology Annual Meeting. March 2009 (Corpus Christi, TX) “Analysis of cp23S Domain V to assess zooxanthellar diversity among clionaid sponges from Caribbean and Pacific reefs.” A. McQuillin*, B. Ramsby*, G. Thomson*, C. Schoenberg, A. Hill, and M.Hill.
11th International Coral Reef Symposium. July, 2008 (Fort Lauderdale, FL, USA) "Cladal diversity in zooxanthellae harbored by sponges of the Clionaidae: A case study involving Cliona varians." Malcolm Hill, April Hill, Ashley McQuillin*, Ericka Poppell, Giles Thomson*, and Blake Ramsby*.
Beckman Scholars Conference. July, 2008 (Irvine, CA) “Early Diversification of the T-box gene family in the Poriferan Lineage,” Kay Holstien* and April Hill.
Society for Integrative and Comparative Biology Annual Meeting, January 2008 (San Antonio, TX). “Zooxanthellar symbionts of the Clionaidae: A case study involving the Cliona varians species complex.” Blake Rambsy*, Brittany West*, Ericka Poppell, April Hill and Malcolm Hill.
Society for Integrative and Comparative Biology Annual Meeting, January 2008 (San Antonio, TX). “Response of microbial symbiont communities and carotenoid profiles to environmental stressors in temperate sponges from the Chesapeake Bay.” Brittany West*, Ashley McQuillin*, Giles Thomson*, Blake Rambsby*, Ericka Poppell, April Hill, Olivia Harriott, Jonathan Dattlebaum, Tim Sherman, and Malcolm Hill.
Society for Integrative and Comparative Biology Annual Meeting, January 2008 (San Antonio, TX). “Early diversification of the T-box gene family in the poriferan lineage.” Kay Holstien*, Malcolm Hill and April Hill.
Publications
Articles
A. Rivera, I. Winters*, A. Rued*, S. Ding*, D. Posfai*, B. Cieniewicz*, K. Cameron, L. Gentile, A. Hill (2013) The evolution and function of the Pax/Six regulatory network in sponges. Evolution and Development. In press.

M. Hill, A. Hill, J. Lopez, K.J. Peterson, S. Pomponi, C. Diaz, R. Thacker, M. Adamska, N. Boury-Esnault, P. Cardenas, A. Chaves-Fonnegra, E. Danka*, B. DeLaine*, D. Formica, E. Hajdu, G. Lobo-Hajdu, S. Klontz, C. Morrow, J. Patel, B. Picton, D. Pisani, D. Pohlmann*, N. Redmond, J. Reed, S. Richie*, A. Riesgo, E. Rubin, Z. Russell*, K. Rutzler, E. Sperling, M. di Stefano*, J. Tarver, A. Collins (2012) Reconstruction of Family-level phylogenetic relationships within Demospongiae (Porifera) using nuclear encoded housekeeping genes. PLoS ONE. In press.

*undergraduate co-authors

C. Richardson*, M. Hill, C. Marks, L. Runyen-Janecky, A. Hill (2012) Experimental manipulation of sponge:bacterial symbiont community composition with antibiotics: sponge cell aggregates as a unique tool to study animal:microbe symbiosis. FEMS Microbiology Ecology. 81: 407-418.

*undergraduate co-author

M. Hill and A. Hill (2012) The magnesium inhibition and arrested phagosome hypotheses: new perspectives on the evolution and ecology of Symbiodinium symbioses. Biological Reviews. 87: 804-821.
L. Gentile, L. Caudill, M. Fetea, A. Hill, K. Hoke, B. Lawson, O. Lipan, M. Kerckhove, C. Parish, K. Stenger, D. Szajda (2012) Challenging disciplinary boundaries in the first-year: A new introductory integrated science course for STEM majors. Journal of College Science Teaching. In press. (Pedagogical Publication)

A. Rivera, J. Hammel, K. Haen, E. Danka*, B. Cieniewicz*, I. Winters*, D. Posfai*, G. Wörheide, D. Lavrov, S. Knight, M. Hill, A. Hill, and M. Nickel (2011) RNA interference in marine and freshwater sponges: actin knockdown in Tethya wilhelma and Ephydatia muelleri by ingested dsRNA expressing bacteria. BMC Biotechnology, 11: 67.  (Highly accessed)

*undergraduate co-authors

M. Hill, A. Allenby*, B. Ramsby*, C. Schönberg and A. Hill (2011) Symbiodinium diversity among host clionaid sponges from Caribbean and Pacific Reefs: evidence of heteroplasmy and putative host-specific symbiont lineages. Molecular Phylogenetics and Evolution.  59: 81-88.

*undergraduate co-authors

K. Holstien*, A. Rivera, S. Ding*, P. Windsor, S. Leys, M. Hill and A. Hill (2010) Expansion, Diversification, and Expression of T-box Family Genes in Porifera. Development, Genes, and Evolution. 220: 251-262.

*undergraduate co-authors

L. Caudill, A. Hill, K. Hoke, and O. Lipan  (2010) Impact of Interdisciplinary Undergraduate Research in Mathematics and Biology in the Development of a New Course Integrating Five STEM Disciplines. CBE – Life Sciences Education. 9: 212-216. (Pedagogical Publication)

A. Hill, W. Boll, C. Ries, L. Warner*, M. Osswalt*, M. Hill and M. Noll (2010) Origin of Pax and Six gene families in sponges: Single PaxB and Six1/2 orthologs in Chalinula loosanoffi. Developmental Biology 343: 106-123.

*undergraduate co-authors

B. West*, J. Brandt*, K. Holstien*, A. Hill, and  M. Hill (2009) Fern-associated arbuscular mycorrhizal fungi are represented by multiple Glomus spp.: do environmental factors influence partner identity? Mycorrhiza 19: 295-304.

*undergraduate co-authors

N. Lemoine*, N. Buell*, A. Hill, and M. Hill. (2007) Assessing the utility of sponge microbial symbiont communities as models to study global climate change: a case study with Halichondria bowerbanki. p. 419-425. In: Hajdu, E., and G. Muricy (eds.). Porifera Research: Biodiversity, Innovation, and Sustainability.

*undergraduate co-authors

M. Hill, A. Hill, N. Lopez* and O. Harriott (2006) Sponge-specific bacterial symbionts in the Caribbean sponge, Chondrilla nucula. Marine Biology. 148: 1221-1230.

*undergraduate co-author

A. Hill, J. Tetrault*, and M. Hill (2004) Isolation and expression analysis of a poriferan Antp-class BarX/Bsh-like homeobox gene. Development, Genes and Evolution. 214 (10): 515-523.

*undergraduate co-author

A. Hill, A. Wagner*, and M. Hill (2003) Hox and paraHox genes from the anthozoan Parazoanthus parasiticus. Molecular Phylogenetics and Evolution. 28: 529-535.

*undergraduate co-author

M. Hill, and A. Hill (2002) "Morphological Plasticity in the tropical sponge Anthosigmella varians:  responses to predators and wave energy" Biological Bulletin. 202: 86-95.

M. Hill, C. Stabile*, L.K. Steffen, and A. Hill (2002) "Toxic Effects of Endocrine Disrupters on Two Species of Freshwater Sponge: Common Developmental Abnormalities." Environmental Pollution. 117: 295-300.

*undergraduate co-author

Chapters
S. Leys and A. Hill (2012) The physiology and molecular biology of sponge tissues in Advances in Marine Biology – Advances in Sponge Science: Physiology, Chemical and Microbial Diversity, Biotechnology, M. Beccero et. al., editors – Vol. 62. Pp. 1-56.
M. Hill and A. Hill. (2009) Porifera (sponges). In: G. Likens (ed.) Encyclopedia of Inland Waters. Elsevier Press, Oxford, UK.

Education
Ph.D., University of Houston
B.S., University of North Texas
Contact Information
(804) 484-1591
(804) 289-8233 (Fax)
Areas of Expertise
Evolutionary Developmental Biology
Gene Regulation and Gene Networks